internal/rosa/package/qemu: 11.0.2 to 11.0.3

Signed-off-by: Ophestra <cat@gensokyo.uk>

.gitattributes

@@ -0,0 +1 @@
+*.az linguist-language=Azalea

.gitea/workflows/release.yml

@@ -14,7 +14,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Build for release
-        run: nix build --print-out-paths --print-build-logs .#dist
+        run: nix build --print-out-paths --print-build-logs ./test#dist
 
       - name: Release
         uses: https://gitea.com/actions/release-action@main

.gitea/workflows/test.yml

@@ -12,7 +12,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Run NixOS test
-        run: nix build --out-link "result" --print-out-paths --print-build-logs .#checks.x86_64-linux.hakurei
+        run: nix build --out-link "result" --print-out-paths --print-build-logs ./test#checks.x86_64-linux.hakurei
 
       - name: Upload test output
         uses: actions/upload-artifact@v3
@@ -29,7 +29,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Run NixOS test
-        run: nix build --out-link "result" --print-out-paths --print-build-logs .#checks.x86_64-linux.race
+        run: nix build --out-link "result" --print-out-paths --print-build-logs ./test#checks.x86_64-linux.race
 
       - name: Upload test output
         uses: actions/upload-artifact@v3
@@ -46,7 +46,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Run NixOS test
-        run: nix build --out-link "result" --print-out-paths --print-build-logs .#checks.x86_64-linux.sandbox
+        run: nix build --out-link "result" --print-out-paths --print-build-logs ./test#checks.x86_64-linux.sandbox
 
       - name: Upload test output
         uses: actions/upload-artifact@v3
@@ -63,7 +63,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Run NixOS test
-        run: nix build --out-link "result" --print-out-paths --print-build-logs .#checks.x86_64-linux.sandbox-race
+        run: nix build --out-link "result" --print-out-paths --print-build-logs ./test#checks.x86_64-linux.sandbox-race
 
       - name: Upload test output
         uses: actions/upload-artifact@v3
@@ -80,7 +80,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Run NixOS test
-        run: nix build --out-link "result" --print-out-paths --print-build-logs .#checks.x86_64-linux.sharefs
+        run: nix build --out-link "result" --print-out-paths --print-build-logs ./test#checks.x86_64-linux.sharefs
 
       - name: Upload test output
         uses: actions/upload-artifact@v3
@@ -103,7 +103,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Run checks
-        run: nix --print-build-logs --experimental-features 'nix-command flakes' flake check
+        run: nix --print-build-logs --experimental-features 'nix-command flakes' flake check ./test
 
   dist:
     name: Create distribution
@@ -116,9 +116,9 @@ jobs:
         id: build-test
         run: >-
           export HAKUREI_REV="$(git rev-parse --short HEAD)" &&
-          sed -i.old 's/version = /version = "0.0.0-'$HAKUREI_REV'"; # version = /' package.nix &&
+          sed -i.old 's/version = /version = "0.0.0-'$HAKUREI_REV'"; # version = /' test/package.nix &&
-          nix build --print-out-paths --print-build-logs .#dist &&
+          nix build --print-out-paths --print-build-logs ./test#dist &&
-          mv package.nix.old package.nix &&
+          mv test/{package.nix.old,package.nix} &&
           echo "rev=$HAKUREI_REV" >> $GITHUB_OUTPUT
 
       - name: Upload test build

.gitignore

@@ -1,4 +1,5 @@
 # produced by tools and text editors
+*.swp
 *.qcow2
 *.test
 *.out

README.md

@@ -58,8 +58,3 @@ package [internal/rosa](https://pkg.go.dev/hakurei.app/internal/rosa).
 
 New dependencies will generally not be added. Patches adding new dependencies
 are very likely to be rejected.
-
-## NixOS Module (deprecated)
-
-The NixOS module is in maintenance mode and will be removed once planterette is
-feature-complete. Full module documentation can be found [here](options.md).

cmd/app/app.go

@@ -4,10 +4,12 @@ import (
 	"bufio"
 	"fmt"
 	"io"
+	"os"
 	"strconv"
 	"strings"
 
 	"hakurei.app/check"
+	"hakurei.app/ext"
 	"hakurei.app/fhs"
 	"hakurei.app/hst"
 )
@@ -31,10 +33,19 @@ func parsePair(s string) (source, target *check.Absolute, err error) {
 
 // parse decodes a high-level configuration stream and returns its
 // corresponding [hst.Config].
-func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
+func parse(
+	id string,
+	base *check.Absolute,
+	r io.Reader,
+	templateP *string,
+) (*hst.Config, error) {
 	shell := fhs.AbsRoot.Append("bin", "zsh")
 	home := hst.AbsPrivateTmp.Append("home")
 
+	root := hst.FSOverlay{
+		Target: fhs.AbsRoot,
+		Lower:  []*check.Absolute{base.Append("initial")},
+	}
 	c := hst.Config{
 		ID:          id,
 		Enablements: new(hst.Enablements),
@@ -51,13 +62,7 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 		Container: &hst.ContainerConfig{
 			Env: make(map[string]string),
 			Filesystem: []hst.FilesystemConfigJSON{
-				{FilesystemConfig: &hst.FSOverlay{
+				{FilesystemConfig: &root},
-					Target: fhs.AbsRoot,
-					Lower: []*check.Absolute{
-						base.Append("template", "initial"),
-					},
-					Upper: base.Append("template", "upper"),
-				}},
 				{FilesystemConfig: &hst.FSBind{
 					Target: home,
 					Source: base.Append("state", id),
@@ -70,12 +75,6 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 					Write:  true,
 					Perm:   01777,
 				}},
-
-				{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("block")}},
-				{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("bus")}},
-				{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("class")}},
-				{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("dev")}},
-				{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("devices")}},
 			},
 
 			Username: "chronos",
@@ -102,19 +101,26 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 	if err := scanOnce(); err != nil {
 		return nil, err
 	}
-	if v, err := strconv.Atoi(s.Text()); err != nil {
+	if template, identity, ok := strings.Cut(s.Text(), ":"); !ok {
+		return nil, io.ErrUnexpectedEOF
+	} else if v, err := strconv.Atoi(identity); err != nil {
 		return nil, err
 	} else {
+		if templateP != nil {
+			*templateP = template
+		}
 		c.Identity = v
+		root.Upper = base.Append("template", template)
 	}
 
 	if err := scanOnce(); err != nil {
 		return nil, err
 	}
-	c.Container.Args = append(c.Container.Args, s.Text())
+	c.Container.Args = append(c.Container.Args, s.Text(), "")
 
-	var flagGPU, flagSystemBus bool
+	var flagInteractive, flagGPU, flagSystemBus bool
 	flags := map[string]*bool{
+		"interactive": &flagInteractive,
 		"gpu":         &flagGPU,
 		"system_bus":  &flagSystemBus,
 	}
@@ -176,10 +182,43 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 		}
 
 		switch key {
+		case "username":
+			c.Container.Username = value
+			continue
+
+		case "hostname":
+			c.Container.Hostname = value
+			continue
+
 		case "group":
 			c.Groups = append(c.Groups, value)
 			continue
 
+		case "sched_policy":
+			if err := c.SchedPolicy.UnmarshalText([]byte(value)); err != nil {
+				return nil, err
+			}
+			continue
+
+		case "sched_priority":
+			v, err := strconv.Atoi(value)
+			if err != nil {
+				return nil, err
+			}
+			c.SchedPriority = ext.Int(v)
+			continue
+
+		case "insecure":
+			switch value {
+			case "pipewire":
+				*c.Enablements |= hst.EPipeWire
+				c.DirectPipeWire = true
+				continue
+
+			default:
+				return nil, fmt.Errorf("invalid insecure flag %q", value)
+			}
+
 		case "env":
 			if key, value, ok = strings.Cut(value, "="); !ok {
 				return nil, fmt.Errorf("invalid environment %q", key)
@@ -200,6 +239,20 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 			)
 			continue
 
+		case "ro+":
+			source, target, err := parsePair(value)
+			if err != nil {
+				return nil, err
+			}
+			c.Container.Filesystem = append(c.Container.Filesystem,
+				hst.FilesystemConfigJSON{FilesystemConfig: &hst.FSBind{
+					Target:   target,
+					Source:   source,
+					Optional: true,
+				}},
+			)
+			continue
+
 		case "rw":
 			source, target, err := parsePair(value)
 			if err != nil {
@@ -214,6 +267,20 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 			)
 			continue
 
+		case "dev":
+			source, target, err := parsePair(value)
+			if err != nil {
+				return nil, err
+			}
+			c.Container.Filesystem = append(c.Container.Filesystem,
+				hst.FilesystemConfigJSON{FilesystemConfig: &hst.FSBind{
+					Target: target,
+					Source: source,
+					Device: true,
+				}},
+			)
+			continue
+
 		case "own":
 			c.SessionBus.Own = append(c.SessionBus.Own, value)
 			continue
@@ -236,6 +303,10 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 		return nil, err
 	}
 
+	if flagInteractive {
+		c.Container.Args[1] += "i"
+	}
+
 	if flagGPU {
 		c.Container.Filesystem = append(c.Container.Filesystem, []hst.FilesystemConfigJSON{
 			{FilesystemConfig: &hst.FSBind{
@@ -250,7 +321,10 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 		c.SystemBus = nil
 	}
 
-	if c.Container.Flags&hst.FShareTmpdir == 0 {
+	if c.Container.Flags&hst.FShareTmpdir == 0 &&
+		(c.Enablements.Unwrap()&hst.EX11 == 0 ||
+			c.Container.Flags&(hst.FHostNet|hst.FHostAbstract) ==
+				hst.FHostNet|hst.FHostAbstract) {
 		c.Container.Filesystem = append(c.Container.Filesystem,
 			hst.FilesystemConfigJSON{FilesystemConfig: &hst.FSEphemeral{
 				Target: fhs.AbsTmp,
@@ -262,3 +336,19 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 
 	return &c, nil
 }
+
+// list prints names of non-hidden entries in pathname.
+func list(pathname *check.Absolute, dir bool) error {
+	dents, err := os.ReadDir(pathname.String())
+	if err != nil {
+		return err
+	}
+	for _, dent := range dents {
+		name := dent.Name()
+		if (dent.IsDir() != dir) || (len(name) > 0 && name[0] == '.') {
+			continue
+		}
+		fmt.Println(dent.Name())
+	}
+	return nil
+}

cmd/app/app_test.go

@@ -20,7 +20,7 @@ func TestParse(t *testing.T) {
 		want *hst.Config
 		err  error
 	}{
-		{"com.discordapp.Discord", `8
+		{"com.discordapp.Discord", `nonfree:8
 exec Discord --ozone-platform-hint=wayland
 
 gpu
@@ -74,9 +74,9 @@ talk com.canonical.Unity
 					{FilesystemConfig: &hst.FSOverlay{
 						Target: fhs.AbsRoot,
 						Lower: []*check.Absolute{
-							base.Append("template", "initial"),
+							base.Append("initial"),
 						},
-						Upper: base.Append("template", "upper"),
+						Upper: base.Append("template", "nonfree"),
 					}},
 					{FilesystemConfig: &hst.FSBind{
 						Target: hst.AbsPrivateTmp.Append("home"),
@@ -91,12 +91,6 @@ talk com.canonical.Unity
 						Perm:   01777,
 					}},
 
-					{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("block")}},
-					{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("bus")}},
-					{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("class")}},
-					{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("dev")}},
-					{FilesystemConfig: &hst.FSBind{Source: fhs.AbsSys.Append("devices")}},
-
 					{FilesystemConfig: &hst.FSBind{
 						Source: check.MustAbs("/sdcard"),
 						Write:  true,
@@ -120,6 +114,7 @@ talk com.canonical.Unity
 				Args: []string{
 					"zsh", "-c",
 					"exec Discord --ozone-platform-hint=wayland",
+					"",
 				},
 
 				Flags: hst.FCoverRun | hst.FUserns | hst.FHostNet | hst.FMapRealUID |
@@ -135,6 +130,7 @@ talk com.canonical.Unity
 				tc.name,
 				base,
 				strings.NewReader(tc.data),
+				nil,
 			)
 
 			if !reflect.DeepEqual(err, tc.err) {

cmd/app/lock.go

@@ -0,0 +1,112 @@
+package main
+
+import (
+	"errors"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+
+	"hakurei.app/check"
+	"hakurei.app/fhs"
+	"hakurei.app/hst"
+	"hakurei.app/internal/env"
+	"hakurei.app/internal/lockedfile"
+	"hakurei.app/internal/outcome"
+)
+
+// MutationConflictError describes an active mutable instance.
+type MutationConflictError string
+
+func (e MutationConflictError) Error() string {
+	return "mutable instance active at " + string(e)
+}
+
+// informTemplate guards intention of a template or its derivatives.
+func informTemplate(base *check.Absolute, name string, mutable bool) (func() error, error) {
+	mu := lockedfile.MutexAt(base.Append("lock", name).String())
+	if unlock, err := mu.Lock(); err != nil {
+		return nil, err
+	} else {
+		defer unlock()
+	}
+
+	marker := base.Append("lock", "."+name)
+	if p, err := os.ReadFile(marker.String()); err == nil {
+		if _, err = os.Stat(fhs.AbsProc.Append(string(p)).String()); err == nil {
+			return nil, MutationConflictError(p)
+		} else if !errors.Is(err, os.ErrNotExist) {
+			return nil, err
+		}
+		log.Printf("removing stale marker by %s", string(p))
+		if err = os.Remove(marker.String()); err != nil {
+			return nil, err
+		}
+	} else if !errors.Is(err, os.ErrNotExist) {
+		return nil, err
+	}
+
+	if !mutable {
+		return nil, nil
+	}
+
+	var active []hst.ID
+	var sc hst.Paths
+	env.CopyPaths().Copy(&sc, new(outcome.Hsu).MustID(nil))
+	entries, copyError := outcome.NewStore(&sc).All()
+	var s hst.State
+	for eh := range entries {
+		s = hst.State{}
+		if _, err := eh.Load(&s); err != nil {
+			return nil, err
+		}
+
+		if s.Validate(0) != nil || len(s.Container.Filesystem) < 1 {
+			continue
+		}
+		root, ok := s.Container.Filesystem[0].FilesystemConfig.(*hst.FSOverlay)
+		if !ok || root == nil {
+			continue
+		}
+
+		if !root.Target.Is(fhs.AbsRoot) ||
+			len(root.Lower) != 1 ||
+			!root.Lower[0].Is(base.Append("initial")) ||
+			!root.Upper.Is(base.Append("template", name)) ||
+			root.Work != nil {
+			continue
+		}
+
+		active = append(active, s.ID)
+	}
+	if err := copyError(); err != nil {
+		return nil, err
+	}
+
+	if len(active) != 0 {
+		var buf strings.Builder
+		buf.WriteString("derivative instances still active:")
+		for _, id := range active {
+			buf.WriteString("\n\t")
+			buf.WriteString(id.String())
+		}
+		return nil, errors.New(buf.String())
+	}
+
+	return func() error { return os.RemoveAll(marker.String()) }, os.WriteFile(
+		marker.String(),
+		[]byte(strconv.Itoa(os.Getpid())),
+		0400,
+	)
+}
+
+// acquireTemplate obtains exclusivity of a template.
+func acquireTemplate(base *check.Absolute, name string) (remove func() error, err error) {
+	return informTemplate(base, name, true)
+}
+
+// enterTemplate checks against exclusivity of a template.
+func enterTemplate(base *check.Absolute, name string) error {
+	_, err := informTemplate(base, name, false)
+	return err
+}

cmd/app/main.go

@@ -7,6 +7,7 @@ package main
 import (
 	"context"
 	"errors"
+	"io"
 	"log"
 	"os"
 	"os/exec"
@@ -33,8 +34,9 @@ func main() {
 	var (
 		flagVerbose  bool
 		flagBase     string
+		flagInsecure bool
 
-		base, template, initial, upper, work *check.Absolute
+		base, template, initial *check.Absolute
 	)
 	c := command.New(os.Stderr, log.Printf, "app", func([]string) (err error) {
 		msg.SwapVerbose(flagVerbose)
@@ -49,9 +51,7 @@ func main() {
 		}
 
 		template = base.Append("template")
-		initial = template.Append("initial")
+		initial = base.Append("initial")
-		upper = template.Append("upper")
-		work = template.Append("work")
 		return
 	}).Flag(
 		&flagVerbose,
@@ -59,8 +59,12 @@ func main() {
 		"Increase log verbosity",
 	).Flag(
 		&flagBase,
-		"d", command.StringFlag("$HAKUREI_APP_PATH"),
+		"d", command.StringFlag("$ROSA_APP_PATH"),
 		"Configuration and state directory",
+	).Flag(
+		&flagInsecure,
+		"insecure", command.BoolFlag(false),
+		"Allow use of insecure compatibility options",
 	)
 
 	{
@@ -70,17 +74,21 @@ func main() {
 		)
 		c.NewCommand(
 			"enter", "Enter mutable state template",
-			func([]string) error {
+			func(args []string) error {
+				if len(args) != 1 {
+					return list(template, true)
+				}
+
 				config := hst.Config{
-					ID: "app.hakurei.mutable",
+					ID: "app.hakurei.mutable." + args[0],
 					Container: &hst.ContainerConfig{
-						Hostname: "mutable",
+						Hostname: args[0] + "-mutable",
 						Filesystem: []hst.FilesystemConfigJSON{
 							{FilesystemConfig: &hst.FSOverlay{
 								Target: fhs.AbsRoot,
 								Lower:  []*check.Absolute{initial},
-								Upper:  upper,
+								Upper:  template.Append(args[0]),
-								Work:   work,
+								Work:   base.Append("work", args[0]),
 							}},
 							{FilesystemConfig: &hst.FSEphemeral{
 								Target: fhs.AbsTmp,
@@ -89,7 +97,8 @@ func main() {
 							}},
 						},
 						Username: "chronos",
-						Flags: hst.FMultiarch |
+						Flags: hst.FNoPlace |
+							hst.FMultiarch |
 							hst.FDevel |
 							hst.FUserns |
 							hst.FHostNet |
@@ -113,7 +122,12 @@ func main() {
 					config.Container.Home = a
 				}
 
-				return run(ctx, msg, &config)
+				remove, err := acquireTemplate(base, args[0])
+				if err != nil {
+					return err
+				}
+				err = run(ctx, msg, false, &config)
+				return errors.Join(err, remove())
 			},
 		).Flag(
 			&flagShell,
@@ -126,29 +140,65 @@ func main() {
 		)
 	}
 
+	{
+		var (
+			flagCommand string
+		)
 		c.NewCommand(
 			"run", "Start the named application",
 			func(args []string) error {
-			if len(args) != 1 {
+				if len(args) < 1 {
-				return errors.New("run requires 1 argument")
+					return list(base.Append("app"), false)
 				}
 
 				var config *hst.Config
+				var r io.Reader
 				f, err := os.Open(base.Append("app", args[0]).String())
 				if err != nil {
 					return err
 				}
-			config, err = parse(args[0], base, f)
+				r = f
+
+				var common *os.File
+				if common, err = os.Open(base.Append("common").String()); err != nil {
+					if !errors.Is(err, os.ErrNotExist) {
+						_ = f.Close()
+						return err
+					}
+				} else {
+					r = io.MultiReader(f, common)
+				}
+
+				var name string
+				config, err = parse(args[0], base, r, &name)
 				if closeErr := f.Close(); err == nil {
 					err = closeErr
 				}
+				if common != nil {
+					if closeErr := common.Close(); err == nil {
+						err = closeErr
+					}
+				}
 				if err != nil {
 					return err
 				}
 
-			return run(ctx, msg, config)
+				if flagCommand != "" {
+					config.Container.Args[2] = flagCommand
+				}
+
+				if err = enterTemplate(base, name); err != nil {
+					return err
+				}
+				return run(ctx, msg, flagInsecure, config, args[1:]...)
 			},
+		).
+			Flag(
+				&flagCommand,
+				"command", command.StringFlag(""),
+				"Override configured command",
 			)
+	}
 
 	c.MustParse(os.Args[1:], func(err error) {
 		if e, ok := errors.AsType[*exec.ExitError](err); ok && e != nil {
@@ -156,7 +206,13 @@ func main() {
 		}
 
 		if w, ok := err.(interface{ Unwrap() []error }); !ok {
+			var m string
+			m, ok = message.GetMessage(err)
+			if !ok {
 				log.Fatal(err)
+				return
+			}
+			log.Fatal(m)
 		} else {
 			errs := w.Unwrap()
 			for i, e := range errs {

cmd/app/run.go

@@ -12,7 +12,13 @@ import (
 )
 
 // run starts a container via cmd/hakurei and returns after it terminates.
-func run(ctx context.Context, msg message.Msg, config *hst.Config) error {
+func run(
+	ctx context.Context,
+	msg message.Msg,
+	insecure bool,
+	config *hst.Config,
+	args ...string,
+) error {
 	c, cancel := context.WithCancel(ctx)
 	defer cancel()
 
@@ -24,7 +30,11 @@ func run(ctx context.Context, msg message.Msg, config *hst.Config) error {
 	if msg.IsVerbose() {
 		cmd.Args = append(cmd.Args, "-v")
 	}
+	if insecure {
+		cmd.Args = append(cmd.Args, "--insecure")
+	}
 	cmd.Args = append(cmd.Args, "run", "3")
+	cmd.Args = append(cmd.Args, args...)
 
 	r, w, err := os.Pipe()
 	if err != nil {

cmd/dist/VERSION

@@ -1 +1 @@
-v0.4.4
+v0.4.5

cmd/dist/main.go

@@ -35,8 +35,11 @@ func getenv(key, fallback string) string {
 
 // mustRun runs a command with the current process's environment and panics
 // on error or non-zero exit code.
-func mustRun(ctx context.Context, name string, arg ...string) {
+func mustRun(ctx context.Context, env []string, name string, arg ...string) {
 	cmd := exec.CommandContext(ctx, name, arg...)
+	if env != nil {
+		cmd.Env = append(cmd.Environ(), env...)
+	}
 	cmd.Stdin, cmd.Stdout, cmd.Stderr = os.Stdin, os.Stdout, os.Stderr
 	if err := cmd.Run(); err != nil {
 		panic(err)
@@ -49,11 +52,12 @@ var comp []byte
 func main() {
 	log.SetFlags(0)
 	log.SetPrefix("")
+	log.SetOutput(os.Stdout)
 
 	verbose := os.Getenv("VERBOSE") != ""
 	runTests := os.Getenv("HAKUREI_DIST_MAKE") == ""
 	version = getenv("HAKUREI_VERSION", strings.TrimSpace(version))
-	prefix := getenv("PREFIX", "/usr")
+	prefix := getenv("PREFIX", "/usr/local")
 	destdir := getenv("DESTDIR", "dist")
 
 	if verbose {
@@ -91,26 +95,37 @@ func main() {
 		verboseFlag = "-buildvcs=false"
 	}
 
-	log.Printf("Building hakurei for %s/%s.", runtime.GOOS, runtime.GOARCH)
+	log.Printf("Building hakurei %s for %s/%s.", version, runtime.GOOS, runtime.GOARCH)
-	mustRun(ctx, "go", "generate", "./...")
+	mustRun(ctx, nil, "go", "generate", "./...")
 	mustRun(
-		ctx, "go", "build",
+		ctx, nil, "go", "build",
 		"-trimpath",
 		verboseFlag, "-o", s,
 		"-ldflags=-s -w "+
 			"-buildid= -linkmode external -extldflags=-static "+
 			"-X hakurei.app/internal/info.buildVersion="+version+" "+
 			"-X hakurei.app/internal/info.hakureiPath="+prefix+"/bin/hakurei "+
-			"-X hakurei.app/internal/info.hsuPath="+prefix+"/bin/hsu "+
+			"-X hakurei.app/internal/info.hsuPath="+prefix+"/bin/hsu",
-			"-X main.hakureiPath="+prefix+"/bin/hakurei",
+		"./cmd/hakurei",
-		"./...",
+		"./cmd/sharefs",
 	)
-	log.Println()
 
+	log.Printf("Building cmd/hsu for %s/%s.", runtime.GOOS, runtime.GOARCH)
+	mustRun(
+		ctx, []string{"CGO_ENABLED=0"}, "go", "build",
+		"-trimpath",
+		verboseFlag, "-o", s,
+		"-ldflags=-s -w "+
+			"-buildid= "+
+			"-X main.hakureiPath="+prefix+"/bin/hakurei",
+		"./cmd/hsu",
+	)
+
+	log.Println()
 	if runTests {
 		log.Println("##### Testing Hakurei.")
 		mustRun(
-			ctx, "go", "test",
+			ctx, nil, "go", "test",
 			"-ldflags=-buildid= -linkmode external -extldflags=-static",
 			"./...",
 		)

cmd/earlyinit/main.go

@@ -7,6 +7,7 @@ package main
 import (
 	"context"
 	"crypto/rand"
+	"io"
 	"log"
 	"os"
 	"os/signal"
@@ -51,13 +52,14 @@ func init() {
 func fatal(v ...any) {
 	log.Println(v...)
 	log.Println("unable to continue, please reboot and resolve the problem manually")
+	log.SetOutput(io.Discard)
 	select {}
 }
 
 // must calls fatal with err if it is non-nil.
 func must(err error) {
 	if err != nil {
-		log.Println(err)
+		fatal(err)
 		select {}
 	}
 }

cmd/earlyinit/modprobe.go

@@ -26,8 +26,9 @@ var _ report.RepresentableError = ModprobeError{}
 func (ModprobeError) Representable() {}
 func (e ModprobeError) Error() string {
 	return fmt.Sprintf(
-		"modprobe exit status %d: %s",
+		"%s (exit status %d)",
-		e.ExitCode, strings.TrimSpace(e.Stderr),
+		strings.TrimPrefix(strings.TrimSpace(e.Stderr), "modprobe: "),
+		e.ExitCode,
 	)
 }
 

cmd/hakurei/print_test.go

@@ -64,7 +64,7 @@ func TestPrintShowInstance(t *testing.T) {
  Identity:       9 (org.chromium.Chromium)
  Enablements:    wayland, dbus, pipewire
  Groups:         video, dialout, plugdev
- Flags:          multiarch, compat, devel, userns, net, abstract, tty, mapuid, device, cover_run, runtime, tmpdir
+ Flags:          multiarch, compat, devel, userns, net, abstract, tty, mapuid, noplace, device, cover_run, runtime, tmpdir
  Home:           /data/data/org.chromium.Chromium
  Hostname:       localhost
  Path:           /run/current-system/sw/bin/chromium
@@ -161,7 +161,7 @@ App
  Identity:       9 (org.chromium.Chromium)
  Enablements:    wayland, dbus, pipewire
  Groups:         video, dialout, plugdev
- Flags:          multiarch, compat, devel, userns, net, abstract, tty, mapuid, device, cover_run, runtime, tmpdir
+ Flags:          multiarch, compat, devel, userns, net, abstract, tty, mapuid, noplace, device, cover_run, runtime, tmpdir
  Home:           /data/data/org.chromium.Chromium
  Hostname:       localhost
  Path:           /run/current-system/sw/bin/chromium
@@ -354,6 +354,7 @@ App
     "tty": true,
     "multiarch": true,
     "map_real_uid": true,
+    "noplace": true,
     "device": true,
     "cover_run": true,
     "share_runtime": true,
@@ -506,6 +507,7 @@ App
     "tty": true,
     "multiarch": true,
     "map_real_uid": true,
+    "noplace": true,
     "device": true,
     "cover_run": true,
     "share_runtime": true,
@@ -705,6 +707,7 @@ func TestPrintPs(t *testing.T) {
       "tty": true,
       "multiarch": true,
       "map_real_uid": true,
+      "noplace": true,
       "device": true,
       "cover_run": true,
       "share_runtime": true,

cmd/mbf/cache.go

@@ -21,13 +21,15 @@ type cache struct {
 	// Should generally not be used directly.
 	c *pkg.Cache
 
-	cures, jobs int
+	attr pkg.CacheAttr
 	// Primarily to work around missing landlock LSM.
 	hostAbstract bool
 	// Set SCHED_IDLE.
 	idle bool
 	// Unset [pkg.CSuppressInit].
 	verboseInit bool
+	// Unset [pkg.CExternShallow].
+	deep bool
 	// Loaded artifact of [rosa.QEMU].
 	qemu pkg.Artifact
 
@@ -47,15 +49,17 @@ func (cache *cache) open() (err error) {
 		return
 	}
 
-	var flags int
 	if cache.idle {
-		flags |= pkg.CSchedIdle
+		cache.attr.Flags |= pkg.CSchedIdle
 	}
 	if cache.hostAbstract {
-		flags |= pkg.CHostAbstract
+		cache.attr.Flags |= pkg.CHostAbstract
 	}
 	if !cache.verboseInit {
-		flags |= pkg.CSuppressInit
+		cache.attr.Flags |= pkg.CSuppressInit
+	}
+	if !cache.deep {
+		cache.attr.Flags |= pkg.CExternShallow
 	}
 
 	done := make(chan struct{})
@@ -77,10 +81,8 @@ func (cache *cache) open() (err error) {
 	cache.c, err = pkg.Open(
 		cache.ctx,
 		cache.msg,
-		flags,
-		cache.cures,
-		cache.jobs,
 		base,
+		&cache.attr,
 	)
 	if err != nil {
 		return
@@ -95,7 +97,7 @@ func (cache *cache) open() (err error) {
 			return
 		}
 		var r rosa.Remote
-		if r, err = rosa.NewRemote(cache.mirror, pub, http.DefaultClient); err != nil {
+		if r, err = rosa.NewRemote(http.DefaultClient, cache.mirror, pub); err != nil {
 			cache.c.Close()
 			return err
 		}

cmd/mbf/daemon_test.go

@@ -28,8 +28,8 @@ func TestNoReply(t *testing.T) {
 	c, err := pkg.Open(
 		t.Context(),
 		message.New(log.New(os.Stderr, "cir: ", 0)),
-		0, 0, 0,
 		check.MustAbs(t.TempDir()),
+		nil,
 	)
 	if err != nil {
 		t.Fatalf("Open: error = %v", err)
@@ -63,7 +63,7 @@ func TestNoReply(t *testing.T) {
 	}
 
 	<-done
-	wantIdent := pkg.MustDecode("fiZf-ZY_Yq6qxJNrHbMiIPYCsGkUiKCRsZrcSELXTqZWtCnESlHmzV5ThhWWGGYG")
+	wantIdent := pkg.MustDecode("bpVsJ69hdKPBntMh_u777g7-quFNVmMlBJQOlM_thiQa9JnOFLAbe5OlR4zNjZ32")
 	if gotIdent := c.Ident(a).Value(); gotIdent != wantIdent {
 		t.Errorf(
 			"cureFromIR: %s, want %s",
@@ -124,7 +124,7 @@ func TestDaemon(t *testing.T) {
 	cancel()
 	<-done
 
-	const want = "fiZf-ZY_Yq6qxJNrHbMiIPYCsGkUiKCRsZrcSELXTqZWtCnESlHmzV5ThhWWGGYG"
+	const want = "bpVsJ69hdKPBntMh_u777g7-quFNVmMlBJQOlM_thiQa9JnOFLAbe5OlR4zNjZ32"
 	if got := filepath.Base(p.String()); got != want {
 		t.Errorf("cureRemote: %s, want %s", got, want)
 	}
@@ -132,8 +132,8 @@ func TestDaemon(t *testing.T) {
 	wantLog := []string{
 		"",
 		"daemon: aborting all pending cures",
-		"daemon: attempting to cancel invalid artifact kQm9fmnCmXST1-MMmxzcau2oKZCXXrlZydo4PkeV5hO_2PKfeC8t98hrbV_ZZx_j",
+		"daemon: attempting to cancel invalid artifact 58Vy_5beLZCvZX__KzRKyIE6vATleaZP1ZBxbqoWnekz9aZ1zkxNgcIUFI5V1_Jf",
-		"daemon: fulfilled artifact fiZf-ZY_Yq6qxJNrHbMiIPYCsGkUiKCRsZrcSELXTqZWtCnESlHmzV5ThhWWGGYG",
+		"daemon: fulfilled artifact " + want,
 	}
 	gotLog := strings.Split(buf.String(), "\n")
 	slices.Sort(gotLog)

cmd/mbf/info.go

@@ -21,7 +21,10 @@ func commandInfo(
 	r *rosa.Report,
 ) (err error) {
 	if len(args) == 0 {
-		return errors.New("info requires at least 1 argument")
+		for _, h := range rosa.Native().CollectAll() {
+			fmt.Println(h)
+		}
+		return nil
 	}
 
 	// recovered by HandleAccess

cmd/mbf/main.go

@@ -27,6 +27,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"strconv"
+	"strings"
 	"sync"
 	"sync/atomic"
 	"syscall"
@@ -202,13 +203,17 @@ func main() {
 		"v", command.BoolFlag(false),
 		"Do not suppress verbose output from init",
 	).Flag(
-		&cm.cures,
+		&cm.attr.Cures,
 		"cures", command.IntFlag(0),
 		"Maximum number of dependencies to cure at any given time",
 	).Flag(
-		&cm.jobs,
+		&cm.attr.Jobs,
 		"jobs", command.IntFlag(0),
 		"Preferred number of jobs to run, when applicable",
+	).Flag(
+		&cm.attr.Load,
+		"load-average", command.IntFlag(0),
+		"Preferred load average number, when applicable",
 	).Flag(
 		&cm.base,
 		"d", command.StringFlag("$MBF_CACHE_DIR"),
@@ -217,6 +222,11 @@ func main() {
 		&cm.mirror,
 		"r", command.StringFlag("$MBF_REMOTE"),
 		"URL of mirror service",
+	).Flag(
+		&cm.deep,
+		"deep", command.BoolFlag(false),
+		"Cure all inputs even when the required artifact is available "+
+			"via the mirror service",
 	).Flag(
 		&cm.idle,
 		"sched-idle", command.BoolFlag(false),
@@ -539,7 +549,9 @@ func main() {
 			if base, err := os.OpenRoot(cm.base); err != nil {
 				return err
 			} else {
-				h = rosa.NewMirror(msg, base.FS(), key)
+				var mux http.ServeMux
+				rosa.NewMirror(msg, base.FS(), key).Register(&mux)
+				h = &mux
 			}
 
 			server := http.Server{Addr: args[0], Handler: h}
@@ -561,28 +573,52 @@ func main() {
 		},
 	)
 
-	{
+	c.NewCommand(
-		var (
+		"snapshot",
-			flagGentoo   string
+		"Populate an empty directory with a static mirror snapshot",
-			flagChecksum string
+		func(args []string) error {
+			if len(args) != 1 {
+				return errors.New("snapshot requires 1 argument")
+			}
+
+			var key ed25519.PrivateKey
+			if p, err := os.ReadFile(filepath.Join(cm.base, "ed25519")); err != nil {
+				return err
+			} else if len(p) != ed25519.PrivateKeySize {
+				return errors.New("invalid private key")
+			} else {
+				key = p
+			}
+
+			var m rosa.Mirror
+			if base, err := os.OpenRoot(cm.base); err != nil {
+				return err
+			} else {
+				m = rosa.NewMirror(msg, base.FS(), key)
+			}
+
+		retry:
+			root, err := os.OpenRoot(args[0])
+			if err != nil {
+				if os.IsNotExist(err) {
+					if err = os.MkdirAll(args[0], 0755); err != nil {
+						return err
+					}
+					goto retry
+				}
+				return err
+			}
+
+			go func() { <-ctx.Done(); _ = root.Close() }()
+			return m.Populate(root)
+		},
 	)
+
+	{
 		c.NewCommand(
 			"stage3",
 			"Check for toolchain 3-stage non-determinism",
 			func(args []string) (err error) {
-				s := rosa.Std
-				if flagGentoo != "" {
-					s -= 3 // magic number to discourage misuse
-
-					var checksum pkg.Checksum
-					if len(flagChecksum) != 0 {
-						if err = pkg.Decode(&checksum, flagChecksum); err != nil {
-							return
-						}
-					}
-					rosa.Native().SetGentooStage3(flagGentoo, checksum)
-				}
-
 				var (
 					pathname *check.Absolute
 					checksum [2]unique.Handle[pkg.Checksum]
@@ -590,7 +626,7 @@ func main() {
 
 				_llvm := rosa.H("llvm")
 				if err = cm.Do(func(cache *pkg.Cache) (err error) {
-					_, llvm := rosa.Native().New(s - 2).Load(_llvm)
+					_, llvm := rosa.Native().New(rosa.Std - 2).Load(_llvm)
 					pathname, _, err = cache.Cure(llvm)
 					return
 				}); err != nil {
@@ -599,7 +635,7 @@ func main() {
 				log.Println("stage1:", pathname)
 
 				if err = cm.Do(func(cache *pkg.Cache) (err error) {
-					_, llvm := rosa.Native().New(s - 1).Load(_llvm)
+					_, llvm := rosa.Native().New(rosa.Std - 1).Load(_llvm)
 					pathname, checksum[0], err = cache.Cure(llvm)
 					return
 				}); err != nil {
@@ -607,7 +643,7 @@ func main() {
 				}
 				log.Println("stage2:", pathname)
 				if err = cm.Do(func(cache *pkg.Cache) (err error) {
-					_, llvm := rosa.Native().New(s).Load(_llvm)
+					_, llvm := rosa.Native().New(rosa.Std).Load(_llvm)
 					pathname, checksum[1], err = cache.Cure(llvm)
 					return
 				}); err != nil {
@@ -628,14 +664,6 @@ func main() {
 				}
 				return
 			},
-		).Flag(
-			&flagGentoo,
-			"gentoo", command.StringFlag(""),
-			"Bootstrap from a Gentoo stage3 tarball",
-		).Flag(
-			&flagChecksum,
-			"checksum", command.StringFlag(""),
-			"Checksum of Gentoo stage3 tarball",
 		)
 	}
 
@@ -648,9 +676,13 @@ func main() {
 			flagNoReply bool
 			flagFaults  bool
 			flagPop     bool
+			flagRebuild bool
 
 			flagBoot bool
 			flagStd  bool
+
+			flagGentoo   string
+			flagChecksum string
 		)
 		c.NewCommand(
 			"cure",
@@ -667,6 +699,18 @@ func main() {
 					t -= 1
 				}
 
+				if flagGentoo != "" {
+					var checksum pkg.Checksum
+					if len(flagChecksum) != 0 {
+						if err := pkg.Decode(&checksum, flagChecksum); err != nil {
+							return err
+						}
+					}
+					rosa.Native().SetGentooStage3(flagGentoo, checksum)
+
+					t -= 3 // magic number to discourage misuse
+				}
+
 				_, a := rosa.Native().New(t).Load(rosa.ArtifactH(unique.Make(args[0])))
 				if a == nil {
 					return fmt.Errorf("unknown artifact %q", args[0])
@@ -676,7 +720,11 @@ func main() {
 				default:
 					var pathname *check.Absolute
 					err := cm.Do(func(cache *pkg.Cache) (err error) {
+						if flagRebuild {
+							pathname, _, err = cache.CureNew(a)
+						} else {
 							pathname, _, err = cache.Cure(a)
+						}
 						return
 					})
 					if err != nil {
@@ -731,7 +779,7 @@ func main() {
 							ctx,
 							a,
 							"", true, os.Stdin, os.Stdout, os.Stderr,
-							rosa.AbsSystem.Append("bin", "mksh"),
+							rosa.AbsSystem.Append("bin", "sh"),
 							"sh",
 						)
 					})
@@ -837,9 +885,97 @@ func main() {
 			&flagPop,
 			"pop", command.BoolFlag(false),
 			"Display and destroy the most recent fault entry",
+		).Flag(
+			&flagRebuild,
+			"rebuild", command.BoolFlag(false),
+			"Always enter the artifact implementation",
+		).Flag(
+			&flagGentoo,
+			"gentoo", command.StringFlag(""),
+			"Bootstrap from a Gentoo stage3 tarball",
+		).Flag(
+			&flagChecksum,
+			"checksum", command.StringFlag(""),
+			"Checksum of Gentoo stage3 tarball",
 		)
 	}
 
+	c.NewCommand(
+		"validate",
+		"Repeatedly cure named artifact to validate determinism",
+		func(args []string) error {
+			stage := rosa.Std
+			if len(args) == 3 {
+				switch args[0] {
+				case "boot":
+					stage -= 2
+				case "std":
+					stage -= 1
+
+				default:
+					return fmt.Errorf("invalid stage %q", args[0])
+				}
+				args = args[1:]
+			}
+
+			if len(args) != 2 {
+				return errors.New("validate requires 2 arguments")
+			}
+
+			n, err := strconv.Atoi(args[0])
+			if err != nil {
+				return fmt.Errorf("invalid passes %q", args[0])
+			}
+
+			if n < 2 {
+				return errors.New("validate must rebuild at least twice")
+			}
+
+			_, a := rosa.Native().New(stage).Load(rosa.ArtifactH(unique.Make(args[1])))
+			if a == nil {
+				return fmt.Errorf("unknown artifact %q", args[1])
+			}
+
+			if !a.IsExclusive() && cm.attr.Jobs < 1 {
+				cm.attr.Jobs = runtime.NumCPU()/n + 1
+			}
+
+			res := make([]unique.Handle[pkg.Checksum], n)
+			if err = cm.Do(func(cache *pkg.Cache) error {
+				errs := make([]error, n)
+				var wg sync.WaitGroup
+				for i := range n {
+					wg.Go(func() {
+						_, res[i], errs[i] = cache.CureNew(a)
+					})
+				}
+				wg.Wait()
+				return errors.Join(errs...)
+			}); err != nil {
+				return err
+			}
+
+			for i := range n - 1 {
+				if res[i] == res[i+1] {
+					continue
+				}
+
+				var buf strings.Builder
+				buf.WriteString("nondeterminism:")
+				for _, o := range res {
+					buf.WriteString("\n\t")
+					buf.WriteString(filepath.Join(
+						cm.base,
+						"checksum",
+						pkg.Encode(o.Value()),
+					))
+				}
+				return errors.New(buf.String())
+			}
+			return nil
+		},
+	)
+
 	cleanC := c.New("clean", "Remove unused entries from the cache")
 	cleanC.NewCommand(
 		"fault",

hst/container.go

@@ -65,6 +65,8 @@ const (
 	// Some programs fail to connect to dbus session running as a different uid,
 	// this option works around it by mapping priv-side caller uid in container.
 	FMapRealUID
+	// FNoPlace disables placement of /etc/passwd and /etc/group.
+	FNoPlace
 
 	// FDevice mount /dev/ from the init mount namespace as is in the container
 	// mount namespace.
@@ -101,6 +103,8 @@ func (flags Flags) String() string {
 		return "tty"
 	case FMapRealUID:
 		return "mapuid"
+	case FNoPlace:
+		return "noplace"
 	case FDevice:
 		return "device"
 	case FCoverRun:
@@ -197,6 +201,8 @@ type containerConfigJSON = struct {
 
 	// Corresponds to [FMapRealUID].
 	MapRealUID bool `json:"map_real_uid"`
+	// Corresponds to [FNoPlace].
+	NoPlace bool `json:"noplace,omitempty"`
 
 	// Corresponds to [FDevice].
 	Device bool `json:"device,omitempty"`
@@ -224,6 +230,7 @@ func (c *ContainerConfig) MarshalJSON() ([]byte, error) {
 		Tty:           c.Flags&FTty != 0,
 		Multiarch:     c.Flags&FMultiarch != 0,
 		MapRealUID:    c.Flags&FMapRealUID != 0,
+		NoPlace:       c.Flags&FNoPlace != 0,
 		Device:        c.Flags&FDevice != 0,
 		CoverRun:      c.Flags&FCoverRun != 0,
 		ShareRuntime:  c.Flags&FShareRuntime != 0,
@@ -266,6 +273,9 @@ func (c *ContainerConfig) UnmarshalJSON(data []byte) error {
 	if v.MapRealUID {
 		c.Flags |= FMapRealUID
 	}
+	if v.NoPlace {
+		c.Flags |= FNoPlace
+	}
 	if v.Device {
 		c.Flags |= FDevice
 	}

hst/container_test.go

@@ -21,8 +21,8 @@ func TestFlagsString(t *testing.T) {
 	}{
 		{"none", 0, "none"},
 		{"none high", hst.FAll + 1, "none"},
-		{"all", hst.FAll, "multiarch, compat, devel, userns, net, abstract, tty, mapuid, device, cover_run, runtime, tmpdir"},
+		{"all", hst.FAll, "multiarch, compat, devel, userns, net, abstract, tty, mapuid, noplace, device, cover_run, runtime, tmpdir"},
-		{"all high", math.MaxUint, "multiarch, compat, devel, userns, net, abstract, tty, mapuid, device, cover_run, runtime, tmpdir"},
+		{"all high", math.MaxUint, "multiarch, compat, devel, userns, net, abstract, tty, mapuid, noplace, device, cover_run, runtime, tmpdir"},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
@@ -53,7 +53,7 @@ func TestContainerConfig(t *testing.T) {
 		{"hostnet hostabstract mapuid", &hst.ContainerConfig{Flags: hst.FHostNet | hst.FHostAbstract | hst.FMapRealUID},
 			`{"env":null,"filesystem":null,"shell":null,"home":null,"args":null,"host_net":true,"host_abstract":true,"map_real_uid":true}`},
 		{"all", &hst.ContainerConfig{Flags: hst.FAll},
-			`{"env":null,"filesystem":null,"shell":null,"home":null,"args":null,"seccomp_compat":true,"devel":true,"userns":true,"host_net":true,"host_abstract":true,"tty":true,"multiarch":true,"map_real_uid":true,"device":true,"cover_run":true,"share_runtime":true,"share_tmpdir":true}`},
+			`{"env":null,"filesystem":null,"shell":null,"home":null,"args":null,"seccomp_compat":true,"devel":true,"userns":true,"host_net":true,"host_abstract":true,"tty":true,"multiarch":true,"map_real_uid":true,"noplace":true,"device":true,"cover_run":true,"share_runtime":true,"share_tmpdir":true}`},
 	}
 
 	for _, tc := range testCases {

hst/fsoverlay.go

@@ -82,9 +82,9 @@ func (o *FSOverlay) Apply(z *ApplyState) {
 			z.Overlay(o.Target, o.Upper, o.Work, o.Lower...)
 		} else {
 			z.OverlayEphemeral(o.Target, slices.Concat(
+				[]*check.Absolute{o.Upper},
 				o.Lower,
-				[]*check.Absolute{o.Upper})...,
+			)...)
-			)
 		}
 	} else {
 		z.OverlayReadonly(o.Target, o.Lower...)

hst/fsoverlay_test.go

@@ -70,7 +70,7 @@ func TestFSOverlay(t *testing.T) {
 			Upper:  m("/tmp/upper"),
 		}, true, container.Ops{&container.MountOverlayOp{
 			Target: m("/"),
-			Lower:  ms("/tmp/.src0", "/tmp/.src1", "/tmp/upper"),
+			Lower:  ms("/tmp/upper", "/tmp/.src0", "/tmp/.src1"),
 			Upper:  fhs.AbsRoot,
 		}}, m("/"), ms("/tmp/upper", "/tmp/.src0", "/tmp/.src1"),
 			"e*/:/tmp/upper:/tmp/.src0:/tmp/.src1"},

hst/hst_test.go

@@ -244,6 +244,7 @@ func TestTemplate(t *testing.T) {
 		"tty": true,
 		"multiarch": true,
 		"map_real_uid": true,
+		"noplace": true,
 		"device": true,
 		"cover_run": true,
 		"share_runtime": true,

internal/env/env.go

@@ -1,21 +1,29 @@
-// Package env provides the [Paths] struct for efficiently building paths from the environment.
+// Package env provides the [Paths] struct for efficiently building paths from
+// the environment.
 package env
 
 import (
+	"errors"
+	"io/fs"
 	"log"
 	"os"
 	"strconv"
 
 	"hakurei.app/check"
+	"hakurei.app/fhs"
 	"hakurei.app/hst"
 )
 
+const VarRunNscd = fhs.Var + "run/nscd"
+
 // Paths holds paths copied from the environment and is used to create [hst.Paths].
 type Paths struct {
 	// TempDir is returned by [os.TempDir].
 	TempDir *check.Absolute
 	// RuntimePath is copied from $XDG_RUNTIME_DIR.
 	RuntimePath *check.Absolute
+	// Whether [VarRunNscd] is a directory.
+	HasNscd bool
 }
 
 // Copy expands [Paths] into [hst.Paths].
@@ -37,14 +45,17 @@ func (env *Paths) Copy(v *hst.Paths, userid int) {
 }
 
 // CopyPaths returns a populated [Paths].
-func CopyPaths() *Paths { return CopyPathsFunc(log.Fatalf, os.TempDir, os.Getenv) }
+func CopyPaths() *Paths {
+	return CopyPathsFunc(log.Fatalf, os.TempDir, os.Getenv, os.Stat)
+}
 
-// CopyPathsFunc returns a populated [Paths],
+// CopyPathsFunc returns a populated [Paths], using the provided [log.Fatalf],
-// using the provided [log.Fatalf], [os.TempDir], [os.Getenv] functions.
+// [os.TempDir], [os.Getenv] functions.
 func CopyPathsFunc(
 	fatalf func(format string, v ...any),
 	tempdir func() string,
 	getenv func(key string) string,
+	stat func(name string) (fs.FileInfo, error),
 ) *Paths {
 	const xdgRuntimeDir = "XDG_RUNTIME_DIR"
 
@@ -61,5 +72,14 @@ func CopyPathsFunc(
 		env.RuntimePath = a
 	}
 
+	if fi, err := stat(VarRunNscd); err != nil {
+		if !errors.Is(err, fs.ErrNotExist) {
+			fatalf("%v", err)
+			panic("unreachable")
+		}
+	} else {
+		env.HasNscd = fi.IsDir()
+	}
+
 	return &env
 }

internal/env/env_test.go

@@ -2,6 +2,7 @@ package env_test
 
 import (
 	"fmt"
+	"io/fs"
 	"reflect"
 	"testing"
 
@@ -104,7 +105,9 @@ func TestCopyPaths(t *testing.T) {
 					t.Fatalf("fatalf: %q, want %q", got, tc.fatal)
 				}
 				panic(stub.PanicExit)
-			}, func() string { return tc.tmp }, func(key string) string { return tc.env[key] })
+			}, func() string { return tc.tmp }, func(key string) string { return tc.env[key] }, func(name string) (fs.FileInfo, error) {
+				return nil, fs.ErrNotExist
+			})
 
 			if tc.fatal != "" {
 				t.Fatalf("copyPaths: expected fatal %q", tc.fatal)

internal/outcome/dispatcher_test.go

@@ -23,6 +23,7 @@ import (
 	"hakurei.app/container/seccomp"
 	"hakurei.app/container/std"
 	"hakurei.app/hst"
+	"hakurei.app/internal/env"
 	"hakurei.app/internal/stub"
 	"hakurei.app/internal/system"
 	"hakurei.app/message"
@@ -174,6 +175,7 @@ func checkOpBehaviour(t *testing.T, testCases []opBehaviourTestCase) {
 		call("cmdOutput", stub.ExpectArgs{container.Nonexistent, os.Stderr, []string{}, "/"}, []byte("0"), nil),
 		call("tempdir", stub.ExpectArgs{}, container.Nonexistent+"/tmp", nil),
 		call("lookupEnv", stub.ExpectArgs{"XDG_RUNTIME_DIR"}, wantRuntimePath, nil),
+		call("stat", stub.ExpectArgs{env.VarRunNscd}, stubFileInfoIsDir(true), nil),
 		call("getuid", stub.ExpectArgs{}, 1000, nil),
 		call("getgid", stub.ExpectArgs{}, 100, nil),
 

internal/outcome/outcome.go

@@ -110,7 +110,7 @@ func newOutcomeState(k syscallDispatcher, msg message.Msg, id *hst.ID, config *h
 		Paths: env.CopyPathsFunc(k.fatalf, k.tempdir, func(key string) string {
 			v, _ := k.lookupEnv(key)
 			return v
-		}),
+		}, k.stat),
 		Container: config.Container,
 	}
 

internal/outcome/run_test.go

@@ -143,10 +143,6 @@ func TestOutcomeRun(t *testing.T) {
 				// spTmpdirOp
 				Bind(m("/tmp/hakurei.0/tmpdir/9"), fhs.AbsTmp, std.BindWritable).
 
-				// spAccountOp
-				Place(m("/etc/passwd"), []byte("chronos:x:1971:100:Hakurei:/data/data/org.chromium.Chromium:/run/current-system/sw/bin/zsh\n")).
-				Place(m("/etc/group"), []byte("hakurei:x:100:\n")).
-
 				// spWaylandOp
 				Bind(m("/tmp/hakurei.0/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/wayland"), m("/run/user/1971/wayland-0"), 0).
 
@@ -453,7 +449,7 @@ func TestOutcomeRun(t *testing.T) {
 
 				Path: m("/nix/store/yqivzpzzn7z5x0lq9hmbzygh45d8rhqd-chromium-start"),
 
-				Flags: hst.FUserns | hst.FHostNet | hst.FMapRealUID | hst.FShareRuntime | hst.FShareTmpdir,
+				Flags: hst.FUserns | hst.FHostNet | hst.FMapRealUID | hst.FNoPlace | hst.FShareRuntime | hst.FShareTmpdir,
 			},
 			SystemBus: &hst.BusConfig{
 				Talk:   []string{"org.bluez", "org.freedesktop.Avahi", "org.freedesktop.UPower"},
@@ -548,8 +544,6 @@ func TestOutcomeRun(t *testing.T) {
 				Tmpfs(m("/run/user/"), xdgRuntimeDirSize, 0755).
 				Bind(m("/tmp/hakurei.0/runtime/1"), m("/run/user/1971"), std.BindWritable).
 				Bind(m("/tmp/hakurei.0/tmpdir/1"), m("/tmp/"), std.BindWritable).
-				Place(m("/etc/passwd"), []byte("u0_a1:x:1971:100:Hakurei:/var/lib/persist/module/hakurei/0/1:/run/current-system/sw/bin/zsh\n")).
-				Place(m("/etc/group"), []byte("hakurei:x:100:\n")).
 				Bind(m("/run/user/1971/wayland-0"), m("/run/user/1971/wayland-0"), 0).
 				Bind(m("/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/pipewire"), m("/run/user/1971/pipewire-0"), 0).
 				Bind(m("/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/bus"), m("/run/user/1971/bus"), 0).
@@ -716,7 +710,7 @@ func (k *stubNixOS) lookupEnv(key string) (string, bool) {
 func (k *stubNixOS) stat(name string) (fs.FileInfo, error) {
 	switch name {
 	case "/var/run/nscd":
-		return nil, nil
+		return stubFileInfoIsDir(true), nil
 	case "/run/user/1971/pulse":
 		return nil, nil
 	case "/run/user/1971/pulse/native":

internal/outcome/shim_test.go

@@ -78,10 +78,6 @@ func TestShimEntrypoint(t *testing.T) {
 			// spTmpdirOp
 			Bind(m("/tmp/hakurei.10/tmpdir/9999"), fhs.AbsTmp, std.BindWritable).
 
-			// spAccountOp
-			Place(m("/etc/passwd"), []byte("chronos:x:1000:100:Hakurei:/data/data/org.chromium.Chromium:/run/current-system/sw/bin/zsh\n")).
-			Place(m("/etc/group"), []byte("hakurei:x:100:\n")).
-
 			// spWaylandOp
 			Bind(m("/tmp/hakurei.10/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/wayland"), m("/run/user/1000/wayland-0"), 0).
 

internal/outcome/spaccount.go

@@ -6,6 +6,7 @@ import (
 	"syscall"
 
 	"hakurei.app/fhs"
+	"hakurei.app/hst"
 	"hakurei.app/internal/validate"
 )
 
@@ -41,6 +42,7 @@ func (s spAccountOp) toContainer(state *outcomeStateParams) error {
 	state.env["USER"] = username
 	state.env["SHELL"] = state.Container.Shell.String()
 
+	if state.Container.Flags&hst.FNoPlace == 0 {
 		state.params.
 			Place(fhs.AbsEtc.Append("passwd"),
 				[]byte(username+":x:"+
@@ -51,6 +53,7 @@ func (s spAccountOp) toContainer(state *outcomeStateParams) error {
 					state.Container.Shell.String()+"\n")).
 			Place(fhs.AbsEtc.Append("group"),
 				[]byte("hakurei:x:"+state.mapgid.String()+":\n"))
+	}
 
 	return nil
 }

internal/outcome/spaccount_test.go

@@ -38,6 +38,7 @@ func TestSpAccountOp(t *testing.T) {
 		{"success fallback username", func(bool, bool) outcomeOp { return spAccountOp{} }, func() *hst.Config {
 			c := hst.Template()
 			c.Container.Username = ""
+			c.Container.Flags = hst.FMapRealUID
 			return c
 		}, nil, []stub.Call{
 			// this op performs basic validation and does not make calls during toSystem
@@ -60,9 +61,7 @@ func TestSpAccountOp(t *testing.T) {
 			// this op configures the container state and does not make calls during toContainer
 		}, &container.Params{
 			Dir: config.Container.Home,
-			Ops: new(container.Ops).
+			Ops: new(container.Ops),
-				Place(m("/etc/passwd"), []byte("chronos:x:1000:100:Hakurei:/data/data/org.chromium.Chromium:/run/current-system/sw/bin/zsh\n")).
-				Place(m("/etc/group"), []byte("hakurei:x:100:\n")),
 		}, paramsWantEnv(config, map[string]string{
 			"HOME":  config.Container.Home.String(),
 			"USER":  config.Container.Username,

internal/outcome/spcontainer.go

@@ -18,13 +18,12 @@ import (
 	"hakurei.app/hst"
 	"hakurei.app/internal/acl"
 	"hakurei.app/internal/dbus"
+	"hakurei.app/internal/env"
 	"hakurei.app/internal/system"
 	"hakurei.app/internal/validate"
 	"hakurei.app/message"
 )
 
-const varRunNscd = fhs.Var + "run/nscd"
-
 func init() { gob.Register(new(spParamsOp)) }
 
 // spParamsOp initialises unordered fields of [container.Params] and the
@@ -136,17 +135,23 @@ type spFilesystemOp struct {
 }
 
 func (s *spFilesystemOp) toSystem(state *outcomeStateSys) error {
-	/* retrieve paths and hide them if they're made available in the sandbox;
+	// retrieve paths and hide them if they're made available in the sandbox
-
+	//
-	this feature tries to improve user experience of permissive defaults, and
+	// this feature tries to improve user experience of permissive defaults, and
-	to warn about issues in custom configuration; it is NOT a security feature
+	// to warn about issues in custom configuration; it is NOT a security feature
-	and should not be treated as such, ALWAYS be careful with what you bind */
+	// and should not be treated as such, ALWAYS be careful with what you bind
 	hidePaths := []string{
 		state.sc.RuntimePath.String(),
 		state.sc.SharePath.String(),
+	}
 
-		// this causes emulated passwd database to be bypassed on some /etc/ setups
+	if state.Paths == nil || state.HasNscd {
-		varRunNscd,
+		hidePaths = append(hidePaths,
+			// this causes emulated passwd database to be bypassed on some /etc/
+			// setups, made optional to avoid needlessly creating it on
+			// non-glibc systems when invoking permissive defaults
+			env.VarRunNscd,
+		)
 	}
 
 	// dbus.Address does not go through syscallDispatcher

internal/pkg/archive.go

@@ -278,6 +278,8 @@ type archiveArtifact struct {
 	f Artifact
 }
 
+var _ CuresExempt = archiveArtifact{}
+
 // NewArchive returns a new [Artifact] backed by the supplied [Artifact]. The
 // source [Artifact] must be a [FileArtifact] and produce a stream compatible
 // with [Reader].
@@ -301,8 +303,8 @@ func init() {
 	})
 }
 
-// Dependencies returns a slice containing the backing file.
+// Inputs returns a slice containing the backing file.
-func (a archiveArtifact) Dependencies() []Artifact {
+func (a archiveArtifact) Inputs() []Artifact {
 	return []Artifact{a.f}
 }
 
@@ -403,3 +405,7 @@ func (a archiveArtifact) Cure(t *TContext) (err error) {
 	}
 	return
 }
+
+// CuresExempt exempts the cheap [KindArchive] implementation often found at
+// the end of a [FileArtifact] pipeline.
+func (archiveArtifact) CuresExempt() {}

internal/pkg/archive_test.go

@@ -186,7 +186,7 @@ func TestArchiveArtifact(t *testing.T) {
 			cureMany(t, c, []cureStep{
 				{"sample", pkg.NewArchive(
 					pkg.NewFile("", buf.Bytes()),
-				), ignorePathname, expectsFS(want), nil},
+				), ignorePathname, expectsFS(want), pkg.WNew, nil},
 			})
 		}, expectsFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -202,7 +202,7 @@ func TestArchiveArtifact(t *testing.T) {
 			"checksum/CBPcoVHuVUTVRCMbRl8J30RSSzm_tyfuXaZ-HlZsanY1sY50meOVmgaWDrGKbx9F/devices/uevent":     {Mode: 0600, Data: []byte("add")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/3oYyAbRJ_we7AgWo1BRcRcnxXFk3mAQ0Qui2nGQMi8GIJNJQtvUC6P2IeoA5mbjD": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CBPcoVHuVUTVRCMbRl8J30RSSzm_tyfuXaZ-HlZsanY1sY50meOVmgaWDrGKbx9F")},
+			"identifier/-zXKfphyWM2Ko7VMVURaEMSuixNokFSe0xFbnwR2RtRtvMrcPGWalV0LIn45PXTY": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CBPcoVHuVUTVRCMbRl8J30RSSzm_tyfuXaZ-HlZsanY1sY50meOVmgaWDrGKbx9F")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 			"work":       {Mode: fs.ModeDir | 0700},

internal/pkg/clean_test.go

@@ -48,7 +48,7 @@ func TestClean(t *testing.T) {
 			"checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb": {Mode: 0400},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/pPRjw2XYgjB5k8dYedwxTBMgHh4_v2JM_G2Vd-skQbAGOOgPsl3CGSUbEF7om_MO": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
+			"identifier/h6qx7m0vsyhO6oLEJgY2rKa1c6RZuIZ4QXxZSh__NZJ9VU0MIj5bFB-KuaPcsfpE": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
 
 			"lock":       {Mode: 0644},
 			"variant":    {Mode: 0400},
@@ -69,7 +69,7 @@ func TestClean(t *testing.T) {
 			"checksum/KgZ-FjbGuU-XP2QEHInpgv-2Zn0cTH5NqFMgTU0XrSdKmSwyC-3baVs1BMCP5spk": {Mode: 0400, Data: []byte("\xfd")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/FMwSBYw22KqM8jZryfY2ChHXpLuVDdWYyNOYdHvIVYk8ujY6UnGRm5brr2sTTfpD": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/KgZ-FjbGuU-XP2QEHInpgv-2Zn0cTH5NqFMgTU0XrSdKmSwyC-3baVs1BMCP5spk")},
+			"identifier/tkrOYhQfTRaArk4nNYNjTmHQUmuJMVIoDeAKIQBm3I4uuMimBKXKMIY2gGZqwQg4": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/KgZ-FjbGuU-XP2QEHInpgv-2Zn0cTH5NqFMgTU0XrSdKmSwyC-3baVs1BMCP5spk")},
 
 			"lock":       {Mode: 0644},
 			"variant":    {Mode: 0400},
@@ -122,16 +122,16 @@ func TestClean(t *testing.T) {
 			"checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE/result": {Mode: 0444},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/Ef8KX6s_rS_nLgze0rj90zKyrGAvOnzyU0DL7nrYQWEG_f4a9pmUKI6HBEMD8AE8": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/H-eSiCo227-xdqyNl2R-5G3eqXPtbb8XegAB70I5OQb2majeZXJoCxTq9wJy5qqv")},
+			"identifier/KpxTUsUfGbsX6C6HU2j9cd9He3_tt2o2m2MgH4m0zial8lmoqSWY-Gc3KrS0k-UK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/H-eSiCo227-xdqyNl2R-5G3eqXPtbb8XegAB70I5OQb2majeZXJoCxTq9wJy5qqv")},
-			"identifier/xoIGLemzLF227e-w_AJcf_1Sgqh2gs3KFgqvOIWUQE-9P_y2vHBMBytL4GRGQqTb": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
+			"identifier/xxQ43VMIS1WHMSEFnUdBNd6pulbtgiTorP_mtJpEsZENYhGBiDEL6Y2D8yqn0Sra": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
 
 			"lock":    {Mode: 0644},
 			"variant": {Mode: 0400},
 			"status":  {Mode: fs.ModeDir | 0700},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
-			"substitute/4bjS-QjGcSV4nth-W6Vg3-wolKmKgiq4Ld2oRIWcOfy6Wi41XXLAWPoo8FcDx6BH": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
+			"substitute/dP-6_wIDRRouOaOF-nkBy-IaUbLdYHbOUTrptu7j_qfW01mnHSjYJ0oykUmvUd2x": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
-			"substitute/dzO8FEY9lu4hwRT6BfRZOX-uYGsC_5XH4jEJ7sJyThcmG9J_w1ArOAaUCGfL8wAM": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
+			"substitute/td1tf1kb3z8iUFg2k1xlHeTTEz3xR4e77WSWdv2JhjmZyY6iuvodhdT8BblDOi0E": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
 
 			"fault": {Mode: fs.ModeDir | 0700},
 			"work":  {Mode: fs.ModeDir | 0700},
@@ -199,18 +199,18 @@ func TestClean(t *testing.T) {
 			"checksum/H-eSiCo227-xdqyNl2R-5G3eqXPtbb8XegAB70I5OQb2majeZXJoCxTq9wJy5qqv":        {Mode: 0400, Data: []byte("kept")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/Ef8KX6s_rS_nLgze0rj90zKyrGAvOnzyU0DL7nrYQWEG_f4a9pmUKI6HBEMD8AE8": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/H-eSiCo227-xdqyNl2R-5G3eqXPtbb8XegAB70I5OQb2majeZXJoCxTq9wJy5qqv")},
+			"identifier/KpxTUsUfGbsX6C6HU2j9cd9He3_tt2o2m2MgH4m0zial8lmoqSWY-Gc3KrS0k-UK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/H-eSiCo227-xdqyNl2R-5G3eqXPtbb8XegAB70I5OQb2majeZXJoCxTq9wJy5qqv")},
-			"identifier/xoIGLemzLF227e-w_AJcf_1Sgqh2gs3KFgqvOIWUQE-9P_y2vHBMBytL4GRGQqTb": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CyDnDvF-LaeGPcSW70tPosNCoclByWkTjznUUF1DcgzlIwkN9yzz1ZFME1TlPj6W")},
+			"identifier/xxQ43VMIS1WHMSEFnUdBNd6pulbtgiTorP_mtJpEsZENYhGBiDEL6Y2D8yqn0Sra": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CyDnDvF-LaeGPcSW70tPosNCoclByWkTjznUUF1DcgzlIwkN9yzz1ZFME1TlPj6W")},
 
 			"lock":    {Mode: 0644},
 			"variant": {Mode: 0400},
 
 			"status": {Mode: fs.ModeDir | 0700},
-			"status/4bjS-QjGcSV4nth-W6Vg3-wolKmKgiq4Ld2oRIWcOfy6Wi41XXLAWPoo8FcDx6BH": {Mode: 0400, Data: []byte(statusHeader + "kept")},
+			"status/xxQ43VMIS1WHMSEFnUdBNd6pulbtgiTorP_mtJpEsZENYhGBiDEL6Y2D8yqn0Sra": {Mode: 0400, Data: []byte(statusHeader + "kept")},
-			"status/xoIGLemzLF227e-w_AJcf_1Sgqh2gs3KFgqvOIWUQE-9P_y2vHBMBytL4GRGQqTb": {Mode: 0400, Data: []byte(statusHeader + "kept")},
+			"status/td1tf1kb3z8iUFg2k1xlHeTTEz3xR4e77WSWdv2JhjmZyY6iuvodhdT8BblDOi0E": {Mode: 0400, Data: []byte(statusHeader + "kept")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
-			"substitute/4bjS-QjGcSV4nth-W6Vg3-wolKmKgiq4Ld2oRIWcOfy6Wi41XXLAWPoo8FcDx6BH": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CyDnDvF-LaeGPcSW70tPosNCoclByWkTjznUUF1DcgzlIwkN9yzz1ZFME1TlPj6W")},
+			"substitute/td1tf1kb3z8iUFg2k1xlHeTTEz3xR4e77WSWdv2JhjmZyY6iuvodhdT8BblDOi0E": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CyDnDvF-LaeGPcSW70tPosNCoclByWkTjznUUF1DcgzlIwkN9yzz1ZFME1TlPj6W")},
 
 			"fault": {Mode: fs.ModeDir | 0700},
 			"work":  {Mode: fs.ModeDir | 0700},
@@ -238,7 +238,7 @@ func TestClean(t *testing.T) {
 			base := makeBase(t)
 			msg := message.New(log.New(os.Stderr, "clean: ", 0))
 			msg.SwapVerbose(testing.Verbose())
-			c, err := pkg.Open(t.Context(), msg, 0, 0, 0, base)
+			c, err := pkg.Open(t.Context(), msg, base, nil)
 			if err != nil {
 				t.Fatal(err)
 			}

internal/pkg/compress.go

@@ -6,6 +6,9 @@ import (
 	"fmt"
 	"io"
 	"os"
+
+	"hakurei.app/internal/xz"
+	"hakurei.app/internal/zstd"
 )
 
 const (
@@ -13,6 +16,10 @@ const (
 	Gzip = iota
 	// Bzip2 denotes a stream compressed via [bzip2].
 	Bzip2
+	// Zstd denotes a stream compressed via [zstd].
+	Zstd
+	// XZ denotes a stream compressed via [xz].
+	XZ
 )
 
 // A decompressArtifact is a [FileArtifact] decompressing a backing
@@ -25,6 +32,7 @@ type decompressArtifact struct {
 }
 
 var _ FileArtifact = new(decompressArtifact)
+var _ CuresExempt = new(decompressArtifact)
 
 // decompressArtifactNamed embeds decompressArtifact for a [fmt.Stringer] stream.
 type decompressArtifactNamed struct {
@@ -65,8 +73,8 @@ func init() {
 	})
 }
 
-// Dependencies returns a slice containing the backing file.
+// Inputs returns a slice containing the backing file.
-func (a *decompressArtifact) Dependencies() []Artifact {
+func (a *decompressArtifact) Inputs() []Artifact {
 	return []Artifact{a.f}
 }
 
@@ -90,6 +98,9 @@ func (c compoundCloser) Close() error {
 	return err
 }
 
+// IsExecutable returns false.
+func (*decompressArtifact) IsExecutable() bool { return false }
+
 // Cure returns a decompressor [io.ReadCloser].
 func (a *decompressArtifact) Cure(r *RContext) (io.ReadCloser, error) {
 	sr, err := r.Open(a.f)
@@ -113,7 +124,28 @@ func (a *decompressArtifact) Cure(r *RContext) (io.ReadCloser, error) {
 			io.Closer
 		}{bzip2.NewReader(br), br}, nil
 
+	case Zstd:
+		return struct {
+			io.Reader
+			io.Closer
+		}{zstd.NewReader(br), br}, nil
+
+	case XZ:
+		var _dr io.Reader
+		if _dr, err = xz.NewReader(br, 0); err != nil {
+			_ = br.Close()
+			return nil, err
+		}
+		return struct {
+			io.Reader
+			io.Closer
+		}{_dr, br}, nil
+
 	default:
 		return nil, os.ErrInvalid
 	}
 }
+
+// CuresExempt exempts the cheap [KindDecompress] implementation often part of
+// a [FileArtifact] pipeline.
+func (*decompressArtifact) CuresExempt() {}

internal/pkg/compress_test.go

@@ -43,7 +43,7 @@ func TestDecompress(t *testing.T) {
 					&client,
 					"file:///testdata",
 					pkg.Checksum{0xfd},
-				), pkg.Gzip), nil, nil, &pkg.ChecksumMismatchError{
+				), pkg.Gzip), nil, nil, pkg.WNew, &pkg.ChecksumMismatchError{
 					Got:  testdataChecksum,
 					Want: pkg.Checksum{0xfd},
 				}},
@@ -52,7 +52,7 @@ func TestDecompress(t *testing.T) {
 					&client,
 					"file:///testdata",
 					testdataChecksum,
-				), pkg.Gzip), ignorePathname, expectsChecksum(sha512.Sum384([]byte{0})), nil},
+				), pkg.Gzip), ignorePathname, expectsChecksum(sha512.Sum384([]byte{0})), pkg.WNew, nil},
 			})
 		}, expectsFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -61,7 +61,7 @@ func TestDecompress(t *testing.T) {
 			"checksum/" + pkg.Encode(sha512.Sum384([]byte{0})): {Mode: 0400, Data: []byte{0}},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/QpjkahDrz7pz-tv0eAGNXR6x9NAtTjWCK5Hr7G1cIZj9rT7bLYJWUQeLD4wamAlF": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX")},
+			"identifier/mae-iR_9LFT_BOEJ2IRzKsAlI754SalMjjt95fZeMd3gEyAzsrvuOXnXN0bFZJi4": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 			"work":       {Mode: fs.ModeDir | 0700},

internal/pkg/exec.go

@@ -30,10 +30,16 @@ import (
 // AbsWork is the container pathname [TContext.GetWorkDir] is mounted on.
 var AbsWork = fhs.AbsRoot.Append("work/")
 
+const (
 	// EnvJobs is the name of the environment variable holding a decimal
 	// representation of the preferred job count. Its value must not affect cure
 	// outcome.
-const EnvJobs = "CURE_JOBS"
+	EnvJobs = "CURE_JOBS"
+	// EnvLoad is the name of the environment variable holding a decimal
+	// representation of the preferred loadavg target. Its value must not affect
+	// cure outcome.
+	EnvLoad = "CURE_LOAD"
+)
 
 // ExecPath is a slice of [Artifact] and the [check.Absolute] pathname to make
 // it available at under in the container.
@@ -407,9 +413,9 @@ func init() {
 		func(r *IRReader) Artifact { return readExecArtifact(r, true) })
 }
 
-// Dependencies returns a slice of all artifacts collected from caller-supplied
+// Inputs returns a slice of all artifacts collected from caller-supplied
 // [ExecPath].
-func (a *execArtifact) Dependencies() []Artifact {
+func (a *execArtifact) Inputs() []Artifact {
 	artifacts := make([][]Artifact, 0, len(a.paths))
 	for _, p := range a.paths {
 		artifacts = append(artifacts, p.A)
@@ -471,7 +477,7 @@ const SeccompPresets = std.PresetStrict &
 func (a *execArtifact) makeContainer(
 	ctx context.Context,
 	msg message.Msg,
-	flags, jobs int,
+	flags, jobs, load int,
 	hostNet bool,
 	temp, work *check.Absolute,
 	getArtifact GetArtifactFunc,
@@ -508,7 +514,10 @@ func (a *execArtifact) makeContainer(
 	z.Quiet = flags&CSuppressInit != 0
 	z.Uid, z.Gid = (1<<10)-1, (1<<10)-1
 	z.Dir, z.Path, z.Args = a.dir, a.path, a.args
-	z.Env = slices.Concat(a.env, []string{EnvJobs + "=" + strconv.Itoa(jobs)})
+	z.Env = slices.Concat(a.env, []string{
+		EnvJobs + "=" + strconv.Itoa(jobs),
+		EnvLoad + "=" + strconv.Itoa(load),
+	})
 	z.Grow(len(a.paths) + 4)
 
 	if a.arch != runtime.GOARCH {
@@ -617,7 +626,7 @@ func (c *Cache) EnterExec(
 		return ErrNotExec
 	}
 
-	deps := Collect(a.Dependencies())
+	deps := Collect(a.Inputs())
 	if _, _, err = c.Cure(&deps); err == nil {
 		return errors.New("unreachable")
 	} else if !IsCollected(err) {
@@ -649,8 +658,9 @@ func (c *Cache) EnterExec(
 	var z *container.Container
 	z, err = e.makeContainer(
 		ctx, c.msg,
-		c.flags,
+		c.attr.Flags,
-		c.jobs,
+		c.attr.Jobs,
+		c.attr.Load,
 		hostNet,
 		temp, work,
 		func(a Artifact) (*check.Absolute, unique.Handle[Checksum]) {
@@ -693,7 +703,7 @@ func (a *execArtifact) cure(f *FContext, hostNet bool) (err error) {
 	msg := f.GetMessage()
 	var z *container.Container
 	if z, err = a.makeContainer(
-		ctx, msg, f.cache.flags, f.GetJobs(), hostNet,
+		ctx, msg, f.cache.attr.Flags, f.GetJobs(), f.GetLoad(), hostNet,
 		f.GetTempDir(), f.GetWorkDir(),
 		f.GetArtifact,
 		f.cache.Ident,

internal/pkg/exec_test.go

@@ -84,7 +84,7 @@ func TestExec(t *testing.T) {
 						},
 					}),
 					pkg.MustPath("/opt", false, testtool),
-				), ignorePathname, wantOffline, nil},
+				), ignorePathname, wantOffline, pkg.WNew, nil},
 
 				{"substitution", pkg.NewExec(
 					"exec-offline", "", new(wantOffline.hash()), 0, false, false,
@@ -108,7 +108,7 @@ func TestExec(t *testing.T) {
 						},
 					}),
 					pkg.MustPath("/opt", false, testtool),
-				), ignorePathname, wantOffline, nil},
+				), ignorePathname, wantOffline, pkg.WSubstitute, nil},
 
 				{"error passthrough", pkg.NewExec(
 					"", "", nil, 0, false, true,
@@ -118,7 +118,7 @@ func TestExec(t *testing.T) {
 					[]string{"testtool"},
 
 					pkg.MustPath("/proc/nonexistent", false, failingArtifact),
-				), nil, nil, &pkg.DependencyCureError{
+				), nil, nil, pkg.WNew, &pkg.DependencyCureError{
 					{
 						A:   failingArtifact,
 						Err: stub.UniqueError(0xcafe),
@@ -133,7 +133,7 @@ func TestExec(t *testing.T) {
 					[]string{"testtool"},
 
 					pkg.ExecPath{},
-				), nil, nil, pkg.ErrInvalidPaths},
+				), nil, nil, pkg.WNew, pkg.ErrInvalidPaths},
 			})
 
 			// check init failure passthrough
@@ -183,11 +183,11 @@ func TestExec(t *testing.T) {
 			"checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb": {Mode: 0400, Data: []byte{}},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/QwS7SmiatdqryQYgESdGw7Yw2PcpNf0vNfpvUA0t92BTlKiUjfCrXyMW17G2X77X": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/MEaM1v6MLRQ60JQOOKbfDzfJOdC3L8i30IgOpYbQdX68enwF0FN-P36_M4RX_0Vd": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 			"identifier/_gAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
 			"identifier/" + expected.Offline:                                              {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantOfflineEncode)},
 			"identifier/" + expected.OfflineS:                                             {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantOfflineEncode)},
-			"identifier/vjz1MHPcGBKV7sjcs8jQP3cqxJ1hgPTiQBMCEHP9BGXjGxd-tJmEmXKaStObo5gK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/_OHzj_xdmfpaWfFN-_D9JpGpPlIjh84873E3Ui9xwv9PPPIt0BlzvH-cnPNeRsTl": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 
@@ -225,7 +225,7 @@ func TestExec(t *testing.T) {
 						},
 					}),
 					pkg.MustPath("/opt", false, testtool),
-				), ignorePathname, wantNet, nil},
+				), ignorePathname, wantNet, pkg.WNew, nil},
 			})
 
 			destroyStatus(t, base, 2, 0)
@@ -242,7 +242,7 @@ func TestExec(t *testing.T) {
 			"identifier":                 {Mode: fs.ModeDir | 0700},
 			"identifier/" + expected.Net: {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/a1F_i9PVQI4qMcoHgTQkORuyWLkC1GLIxOhDt2JpU1NGAxWc5VJzdlfRK-PYBh3W")},
 			"identifier/_gAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
-			"identifier/vjz1MHPcGBKV7sjcs8jQP3cqxJ1hgPTiQBMCEHP9BGXjGxd-tJmEmXKaStObo5gK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/MEaM1v6MLRQ60JQOOKbfDzfJOdC3L8i30IgOpYbQdX68enwF0FN-P36_M4RX_0Vd": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 
@@ -269,7 +269,7 @@ func TestExec(t *testing.T) {
 						},
 					}),
 					pkg.MustPath("/opt", false, testtool),
-				), ignorePathname, wantOffline, nil},
+				), ignorePathname, wantOffline, pkg.WNew, nil},
 			})
 
 			destroyStatus(t, base, 2, 0)
@@ -284,7 +284,7 @@ func TestExec(t *testing.T) {
 
 			"identifier":                     {Mode: fs.ModeDir | 0700},
 			"identifier/" + expected.OvlRoot: {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantOfflineEncode)},
-			"identifier/vjz1MHPcGBKV7sjcs8jQP3cqxJ1hgPTiQBMCEHP9BGXjGxd-tJmEmXKaStObo5gK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/MEaM1v6MLRQ60JQOOKbfDzfJOdC3L8i30IgOpYbQdX68enwF0FN-P36_M4RX_0Vd": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 
@@ -316,7 +316,7 @@ func TestExec(t *testing.T) {
 							return os.MkdirAll(t.GetWorkDir().String(), 0700)
 						},
 					}), pkg.Path(pkg.AbsWork, false /* ignored */, testtool),
-				), ignorePathname, wantOffline, nil},
+				), ignorePathname, wantOffline, pkg.WNew, nil},
 			})
 
 			destroyStatus(t, base, 2, 0)
@@ -331,7 +331,7 @@ func TestExec(t *testing.T) {
 
 			"identifier":                  {Mode: fs.ModeDir | 0700},
 			"identifier/" + expected.Work: {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantOfflineEncode)},
-			"identifier/vjz1MHPcGBKV7sjcs8jQP3cqxJ1hgPTiQBMCEHP9BGXjGxd-tJmEmXKaStObo5gK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/MEaM1v6MLRQ60JQOOKbfDzfJOdC3L8i30IgOpYbQdX68enwF0FN-P36_M4RX_0Vd": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 
@@ -385,7 +385,7 @@ func TestExec(t *testing.T) {
 						},
 					}),
 					pkg.MustPath("/opt", false, testtool),
-				), ignorePathname, wantOffline, nil},
+				), ignorePathname, wantOffline, pkg.WNew, nil},
 			})
 
 			destroyStatus(t, base, 2, 0)
@@ -403,9 +403,9 @@ func TestExec(t *testing.T) {
 
 			"identifier": {Mode: fs.ModeDir | 0700},
 			"identifier/_gAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
-			"identifier/B-kc5iJMx8GtlCua4dz6BiJHnDAOUfPjgpbKq4e-QEn0_CZkSYs3fOA1ve06qMs2": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/nY_CUdiaUM1OL4cPr5TS92FCJ3rCRV7Hm5oVTzAvMXwC03_QnTRfQ5PPs7mOU9fK")},
+			"identifier/2uIvmnqtzAx4Ed4PWV8xjZCWeJCwfE2IcCc0evM-Nd8mDUlgSU6nLtPLcpPUcMlG": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/nY_CUdiaUM1OL4cPr5TS92FCJ3rCRV7Hm5oVTzAvMXwC03_QnTRfQ5PPs7mOU9fK")},
 			"identifier/" + expected.Layers:                                               {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantOfflineEncode)},
-			"identifier/vjz1MHPcGBKV7sjcs8jQP3cqxJ1hgPTiQBMCEHP9BGXjGxd-tJmEmXKaStObo5gK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/MEaM1v6MLRQ60JQOOKbfDzfJOdC3L8i30IgOpYbQdX68enwF0FN-P36_M4RX_0Vd": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 
@@ -438,7 +438,7 @@ func TestExec(t *testing.T) {
 						},
 					}),
 					pkg.MustPath("/opt", false, testtool),
-				), ignorePathname, wantOffline, nil},
+				), ignorePathname, wantOffline, pkg.WNew, nil},
 			})
 
 			destroyStatus(t, base, 2, 0)
@@ -452,8 +452,8 @@ func TestExec(t *testing.T) {
 			"checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU": {Mode: fs.ModeDir | 0500},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/kvJIqZo5DKFOxC2ZQ-8_nPaQzEAz9cIm3p6guO-uLqm-xaiPu7oRkSnsu411jd_U": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/Vzj9qaSVBtNyBQv_PW6uojFOWTwraHoaC0C6xdaGG1q_HTvSh4KLVxRcEQU1jd2Y": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
-			"identifier/vjz1MHPcGBKV7sjcs8jQP3cqxJ1hgPTiQBMCEHP9BGXjGxd-tJmEmXKaStObo5gK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/MEaM1v6MLRQ60JQOOKbfDzfJOdC3L8i30IgOpYbQdX68enwF0FN-P36_M4RX_0Vd": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 			"identifier/" + expected.Promote:                                              {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantOfflineEncode)},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
@@ -503,7 +503,7 @@ func TestExec(t *testing.T) {
 					".": {Mode: fs.ModeDir | 0500},
 
 					"check": {Mode: 0400, Data: []byte("binfmt")},
-				}, nil},
+				}, pkg.WNew, nil},
 			})
 
 			destroyStatus(t, base, 2, 0)
@@ -519,9 +519,9 @@ func TestExec(t *testing.T) {
 			"checksum/UnDo4B5KneEUY5b4vRUk_y9MWgkWuw2N8f8a2XayO686xXur-aZmX2-7n_8tKMe3/check":      {Mode: 0400, Data: []byte("binfmt")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/6VQTJ1lI5BmVuI1YFYJ8ClO3MRORvTTrcWFDcUU-l5Ga8EofxCxGlSTYN-u8dKj_": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UnDo4B5KneEUY5b4vRUk_y9MWgkWuw2N8f8a2XayO686xXur-aZmX2-7n_8tKMe3")},
+			"identifier/c-HodmoEG0f_WGdst9aN-duLMH7QDDXOUi7UcyArXMeM1fc9lYKKQlTCW8ktaK8X": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UnDo4B5KneEUY5b4vRUk_y9MWgkWuw2N8f8a2XayO686xXur-aZmX2-7n_8tKMe3")},
 			"identifier/_v8AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/5aevg3YpDxjqQZ-pdvXK7YqgkL5JKqcoStYQxeD96kuYar6K2mRQWMHib6NQRnpV")},
-			"identifier/vjz1MHPcGBKV7sjcs8jQP3cqxJ1hgPTiQBMCEHP9BGXjGxd-tJmEmXKaStObo5gK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/MEaM1v6MLRQ60JQOOKbfDzfJOdC3L8i30IgOpYbQdX68enwF0FN-P36_M4RX_0Vd": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 

internal/pkg/file.go

@@ -11,6 +11,8 @@ import (
 type fileArtifact []byte
 
 var _ KnownChecksum = new(fileArtifact)
+var _ CuresExempt = new(fileArtifact)
+var _ RevisionArtifact = new(fileArtifact)
 
 // fileArtifactNamed embeds fileArtifact alongside a caller-supplied name.
 type fileArtifactNamed struct {
@@ -62,8 +64,8 @@ func init() {
 	})
 }
 
-// Dependencies returns a nil slice.
+// Inputs returns a nil slice.
-func (*fileArtifact) Dependencies() []Artifact { return nil }
+func (*fileArtifact) Inputs() []Artifact { return nil }
 
 // IsExclusive returns false: Cure returns a prepopulated buffer.
 func (*fileArtifact) IsExclusive() bool { return false }
@@ -75,7 +77,24 @@ func (a *fileArtifact) Checksum() Checksum {
 	return Checksum(h.Sum(nil))
 }
 
+// Revision satisfies [RevisionArtifact] for incompatible IsExecutable behaviour.
+func (*fileArtifact) Revision() uint64 { return 0 }
+
+// IsExecutable returns whether the contents begin with shebang or the ELF
+// magic number.
+func (a *fileArtifact) IsExecutable() bool {
+	return a != nil &&
+		(bytes.HasPrefix(
+			*a, []byte{'#', '!'},
+		) || bytes.HasPrefix(
+			*a, []byte{0x7f, 'E', 'L', 'F'},
+		))
+}
+
 // Cure returns the caller-supplied data.
 func (a *fileArtifact) Cure(*RContext) (io.ReadCloser, error) {
 	return io.NopCloser(bytes.NewReader(*a)), nil
 }
+
+// CuresExempt exempts the cheap [KindFile] implementation.
+func (*fileArtifact) CuresExempt() {}

internal/pkg/file_test.go

@@ -12,22 +12,41 @@ func TestFile(t *testing.T) {
 	t.Parallel()
 
 	want := expectsFile{0}
+	const ident = "N7M6W8-e55Wky_1q1a6qRKFVDw1S5XtPdB4HE2YZObG8OFum8HittyJgZUG5Ru2u"
+	wantShebang := expectsFile("#!/bin/sh\n")
+	const identShebang = "oKTGZb_TRtJf5G1iGGj4SOx1WUbI6YhmsUeEsCNvmK9tZYRwdwQf-DLFUxRPx5qm"
+	wantELF := expectsFile("\x7fELF\xde\xad\xbe\xef")
+	const identELF = "LjeHmIJgD1SiXIH8ewpGRed2_LU84NLapstnOAa_0hxLd8YY7x4KM0aApsj-RwCh"
 	checkWithCache(t, []cacheTestCase{
 		{"file", pkg.CValidateKnown, nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
 			cureMany(t, c, []cureStep{
-				{"short", pkg.NewFile("null", []byte{0}), base.Append(
+				{"short", pkg.NewFile("null", want), base.Append(
 					"identifier",
-					"3376ALA7hIUm2LbzH2fDvRezgzod1eTK_G6XjyOgbM2u-6swvkFaF0BOwSl_juBi",
+					ident,
-				), want, nil},
+				), want, pkg.WNew, nil},
+
+				{"shebang", pkg.NewFile("shebang", wantShebang), base.Append(
+					"identifier",
+					identShebang,
+				), wantShebang, pkg.WNew, nil},
+
+				{"elf", pkg.NewFile("ELF", wantELF), base.Append(
+					"identifier",
+					identELF,
+				), wantELF, pkg.WNew, nil},
 			})
 		}, expectsFS{
 			".": {Mode: fs.ModeDir | 0700},
 
 			"checksum":                                   {Mode: fs.ModeDir | 0700},
-			"checksum/" + pkg.Encode(want.hash()): {Mode: 0400, Data: []byte{0}},
+			"checksum/" + pkg.Encode(want.hash()):        {Mode: 0400, Data: want},
+			"checksum/" + pkg.Encode(wantShebang.hash()): {Mode: 0500, Data: wantShebang},
+			"checksum/" + pkg.Encode(wantELF.hash()):     {Mode: 0500, Data: wantELF},
 
 			"identifier":                 {Mode: fs.ModeDir | 0700},
-			"identifier/3376ALA7hIUm2LbzH2fDvRezgzod1eTK_G6XjyOgbM2u-6swvkFaF0BOwSl_juBi": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX")},
+			"identifier/" + ident:        {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + pkg.Encode(want.hash()))},
+			"identifier/" + identShebang: {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + pkg.Encode(wantShebang.hash()))},
+			"identifier/" + identELF:     {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + pkg.Encode(wantELF.hash()))},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 

internal/pkg/internal/testtool/expected/sum_amd64.go

@@ -1,11 +1,11 @@
 package expected
 
 const (
-	Offline  = "q5ktDTq0miP-VvB2blxqXQeaRXCUWgP_KbC18KNtUDtyoaI_h5mHmGuPMArVEBDs"
+	Offline  = "IKmVhALejtYA3JhN1PCfjKF-Dio1XVcOeMWDHhfSHCbb4iBNhGjFy2UspZveZvb8"
-	OfflineS = "IY91PCtOpCYy21AaIK0c9f8-Z6fb2_2ewoHWkt4dxoLf0GOrWqS8yAGFLV84b1Dw"
+	OfflineS = "6ZubjSyCnz4-TKgQZi_BbY-JUwsStYCtD_f-BTDOOotfEbqkm47W20AazHRaLviz"
-	OvlRoot  = "NacZGXwuRkTvcHaG08a22ujJ8qCWN0RSoFlRSR5FSt0ZcBbJ28FRvkYsHEtX7G8i"
+	OvlRoot  = "Yox7WpG8B_OqIXWF4HWFZkUfsEl7DGzpFyZM0qtd9T8nQ-7SAkEUurlAe6_DJ6Iu"
-	Layers   = "WBJDrATtX6rIE5yAu8ePX3WmDF0Tt9kFiue0m3cRnyRoVx1my8a67fh3CAW486oP"
+	Layers   = "aAwfxDB-efVo379FNl178jK7HEKU3LEjHbZdaVVjk7GnXGZGEANNsXnB3SCUxM9A"
-	Net      = "CmYtj2sNB3LHtqiDuck_Lz3MjLLIiwyP8N4NDitQ1Icvv__LVP9p8tm-sHeQaKKp"
+	Net      = "IU3GwU2jTBd7HjotvFo2wsDWBQGVGpamwiSKdc2G1EnhM-ZaacxAuK6q0wbTVxra"
-	Promote  = "TX3eCloaQFkV-SZIH6Jg6E5WKH--rcXY1P0jnZKmLFKWrNqnOzd4G9eIBh6i5ywN"
+	Promote  = "rOjetGHzT_jPErrBR24IAZKDj8Q9dLLqxFQqloMgjsULss0VXDI--n6LxuMBHvmZ"
-	Work     = "OuNiLSC68pZhAOr1YQ4WbV1tzASA0nxLEBcK7lO7MqxDY_j8dmP_C612RTuF23Lu"
+	Work     = "7f9XDeREfvJIjCe0qesND0s0tasExAIcc-OH33-eq9tsrQPUXhJp4KEkpsYH4hCD"
 )

internal/pkg/internal/testtool/expected/sum_arm64.go

@@ -1,11 +1,11 @@
 package expected
 
 const (
-	Offline  = "WapqyoPxbWSnq07dWHt71mHaJXq99pAjJfFlELlJljSiZMhTFqqlzU1_mN86shSj"
+	Offline  = "MTgCSzwPrzGigp9phvDPRwUTNGLm1KM2EsEtbz-l2cNieqjaGtnzm65CDXlSxXrl"
-	OfflineS = "ibQZHcdXgNQ1OiMX1FrburBbGPVvKEHvPilbQCkm_0oV0BQCHomyyTbYNrFMGIwl"
+	OfflineS = "p89bQg7_jR4nwaSbpEd08ne1jHOEw7Wlnlyv5FHq7ba1Kml3HSBZwEKRzu0gCqEb"
-	OvlRoot  = "V9anFOiRvjGfAeBhLl14AL8TKdWZyD0WTPYe4fS9mOBw8iW5Lmarvt6TG6MV8uWm"
+	OvlRoot  = "9ifwO6MAaV9kTqRR2O5PJzm8XhfXbr50mFLWyEHQm8OHHcJtAEUgXZzJYoZt9YVV"
-	Layers   = "tKx7JNRoSBdK_7MdzI-nwTNV2wmiPzwYdcd17oLmXKL_iLmUzUiA79qTqdrTasrv"
+	Layers   = "INuGActFPwJtS7mAR9Bkt7FD4yoHlXHSJ9CaSAQJrpkUBL_k815Cs_jvRfxy5-a7"
-	Net      = "aXyDLzBCJ9XltXZIfetEVsEkrqHfcXuD5XE_FcUnYbN3emwL55N6P8LlHzNfGnM5"
+	Net      = "kJvy24uk4ePvHoxSKf4vMOhR4NxLbmyWlA9bTS7d3z3fE9WF1Tvpao9g-QuYU4vm"
-	Promote  = "3k4V16n96Lq04gjFSKmm4sFjyQ883FFBNXgTy9s_DjeTwxT3pg_iacEh8yMb_S4m"
+	Promote  = "lYqyYrfjPawIbld5Qz0NbKvd_bmI3nJC1eEnlIQWzsjWE9uA1HuKPAaClnDeyG6L"
-	Work     = "6Q49MhFWRE3Ne6MycwAotgl1GtoU5WCHqJNWG2byYZCY-zX-IxPrWiKk7bKkNzhE"
+	Work     = "V6k4FqOBMRCmHiqchs5-joVGZ_MhNWZyXm3gdbU0S7S5eMze7G4SwYMTf66ojKQL"
 )

internal/pkg/internal/testtool/expected/sum_riscv64.go

@@ -1,11 +1,11 @@
 package expected
 
 const (
-	Offline  = "Z6yXE5gOJScL3srmnVMWgCXccDiUNZ5snSrf6RkXuU1_U0rX_kGVwsfHUgNG_awd"
+	Offline  = "LlieSHVDe1lnKvfI8t4oGRg_2hPxwyy1drmaqc-EKCOENuS9C2YHrp2VY5pSyhbg"
-	OfflineS = "zN16xv6LKRJRipUJwupyxg2rZcvf-qpsMn_qCxUmgxlTSuNwYI70ZEb7dHW5k0gO"
+	OfflineS = "qccjM8oYjUuEYPKFFzAxDFVzMerSUKUZc18NdVQoiPWf-70XOsNK8NaUQqjTgTAD"
-	OvlRoot  = "zYXJHFRLuxvUhuisZEXgGgVvdQd6piMfp5jmtT6jdVjvC2gICXquOq-UTwlrSD5I"
+	OvlRoot  = "lpV2bb_KGYFHPiOn-jtGop8K_ew0y1p3BezRp0ebM93_a-T9J-vkqGD5uokda1aN"
-	Layers   = "_F8EDazHbcLeT0sVSQXRN_kn9IjduqJcDYgzXpsT-hpKU4EBcZ0PISN2zchpqMbm"
+	Layers   = "sM3DJm210CHPGHkAquIbrXhspB81FpVC60ApQrvJGD5El2i7cSONj7LWf7EWqKpT"
-	Net      = "CA_FAaSIYJgapBEHV40doxpH23PdUEy_6s1TZc7wfSPN0XYqwGpMceXXDSabGveO"
+	Net      = "JihQUwsVETRYjb2-yIXLYZ6WVsaFebwl8btSYAsNQ2QapS5MZVaI-dYwrVoySycR"
-	Promote  = "_3LPrLp--4h9k4GsNNApu9hHtAafq-GUhfU6d4hJKBDKT3bz_szOsvkXxc5sK53d"
+	Promote  = "lGqwR4W2OjylSVitMQP1lc6wApOBkbMjsmIqkxQbfEZ3DHEQBbJr84ErW6Xb54zo"
-	Work     = "FEgHeiCD_WT4wsfB-9kDH5n6cRWCEYtJmXdKZgmUUukAOoXumH_hLlosXREC-tqq"
+	Work     = "aZgtyv6aMtoHFkHAaJr6nLaA7N_SHjShgWPyQ5UdzaIqYSiVqvCrZqSokGTCcTii"
 )

internal/pkg/internal/testtool/main.go

@@ -38,7 +38,15 @@ func main() {
 	}
 
 	environ := slices.DeleteFunc(slices.Clone(os.Environ()), func(s string) bool {
-		return s == "CURE_JOBS="+strconv.Itoa(runtime.NumCPU())
+		for _, t := range []string{
+			"CURE_JOBS=" + strconv.Itoa(runtime.NumCPU()),
+			"CURE_LOAD=" + strconv.Itoa(runtime.NumCPU()+2),
+		} {
+			if s == t {
+				return true
+			}
+		}
+		return false
 	})
 
 	var hostNet, layers, promote bool

internal/pkg/ir.go

@@ -90,7 +90,7 @@ type IContext struct {
 	// returns and must not be exposed directly.
 	w io.Writer
 	// Optional [Artifact] to cureRes cache, replaces [IRKindIdent] with
-	// checksum values if non-nil.
+	// checksum values if non-nil. The pathname field may not be populated.
 	inputs map[Artifact]cureRes
 }
 
@@ -173,7 +173,7 @@ func (i *IContext) mustWrite(p []byte) {
 
 // WriteIdent writes the identifier of [Artifact] to the IR. The behaviour of
 // WriteIdent is not defined for an [Artifact] not part of the slice returned by
-// [Artifact.Dependencies].
+// [Artifact.Inputs].
 func (i *IContext) WriteIdent(a Artifact) {
 	buf := i.ic.getIdentBuf()
 	defer i.ic.putIdentBuf(buf)
@@ -235,13 +235,14 @@ func (ic *irCache) Encode(w io.Writer, a Artifact) (err error) {
 }
 
 // encode implements Encode but replaces identifiers with their cured checksums
-// for a non-nil ident. Caller must acquire Cache.identMu.
+// for a non-nil ident. The pathname field is unused. Caller must acquire
+// Cache.identMu.
 func (ic *irCache) encode(
 	w io.Writer,
 	a Artifact,
 	inputs map[Artifact]cureRes,
 ) (err error) {
-	deps := a.Dependencies()
+	deps := a.Inputs()
 	idents := make([]*extIdent, len(deps))
 	if inputs == nil {
 		for i, d := range deps {
@@ -277,10 +278,11 @@ func (ic *irCache) encode(
 		return *a == *b
 	})
 
-	// kind uint64 | deps_sz uint64
+	// kind uint64 | rev uint64 | deps_sz uint64
-	var buf [wordSize * 2]byte
+	var buf [wordSize * 3]byte
 	binary.LittleEndian.PutUint64(buf[:], uint64(a.Kind()))
-	binary.LittleEndian.PutUint64(buf[wordSize:], uint64(len(idents)))
+	binary.LittleEndian.PutUint64(buf[wordSize:], GetRevision(a))
+	binary.LittleEndian.PutUint64(buf[wordSize*2:], uint64(len(idents)))
 	if _, err = w.Write(buf[:]); err != nil {
 		return
 	}
@@ -330,7 +332,7 @@ func (ic *irCache) encodeAll(
 		return
 	}
 
-	for _, d := range a.Dependencies() {
+	for _, d := range a.Inputs() {
 		if err = ic.encodeAll(w, d, encoded); err != nil {
 			return
 		}
@@ -432,9 +434,9 @@ type (
 		// Common buffer for word-sized reads.
 		buf [wordSize]byte
 
-		// Dependencies sent before params, sorted by identifier. Resliced on
+		// Inputs sent before params, sorted by identifier. Resliced on
 		// each call to Next and checked to be depleted during Finalise.
-		deps []*extIdent
+		inputs []*extIdent
 
 		// Number of values already read, -1 denotes a finalised IRReader.
 		count int
@@ -518,7 +520,7 @@ const (
 	irMaxValues = 1 << 12
 
 	// irMaxDeps is the arbitrary maximum number of direct dependencies allowed
-	// to be returned by [Artifact.Dependencies] and subsequently decoded by
+	// to be returned by [Artifact.Inputs] and subsequently decoded by
 	// [IRDecoder].
 	irMaxDeps = 1 << 10
 )
@@ -603,17 +605,17 @@ func (ir *IRReader) mustReadHeader(k IRValueKind) {
 
 // putAll returns all dependency buffers to the underlying [Cache].
 func (ir *IRReader) putAll() {
-	for _, buf := range ir.deps {
+	for _, buf := range ir.inputs {
 		ir.d.c.putIdentBuf(buf)
 	}
-	ir.deps = nil
+	ir.inputs = nil
 }
 
 // DiscardAll discards all unstructured dependencies. This is useful to
 // implementations that encode dependencies as [IRKindIdent] which are read back
 // via ReadIdent.
 func (ir *IRReader) DiscardAll() {
-	if ir.deps == nil {
+	if ir.inputs == nil {
 		panic("attempting to discard dependencies twice")
 	}
 	ir.putAll()
@@ -625,13 +627,13 @@ var ErrDependencyDepleted = errors.New("reading past end of dependencies")
 
 // Next returns the next unstructured dependency.
 func (ir *IRReader) Next() Artifact {
-	if len(ir.deps) == 0 {
+	if len(ir.inputs) == 0 {
 		panic(ErrDependencyDepleted)
 	}
 
-	id := unique.Make(ID(ir.deps[0][wordSize:]))
+	id := unique.Make(ID(ir.inputs[0][wordSize:]))
-	ir.d.c.putIdentBuf(ir.deps[0])
+	ir.d.c.putIdentBuf(ir.inputs[0])
-	ir.deps = ir.deps[1:]
+	ir.inputs = ir.inputs[1:]
 
 	if a, ok := ir.d.ident[id]; !ok {
 		ir.putAll()
@@ -684,8 +686,8 @@ func (ir *IRReader) Finalise() (checksum unique.Handle[Checksum], ok bool) {
 	}
 	ir.r, ir.ibw = nil, nil
 
-	if len(ir.deps) != 0 {
+	if len(ir.inputs) != 0 {
-		panic(MissedDependencyError(len(ir.deps)))
+		panic(MissedDependencyError(len(ir.inputs)))
 	}
 
 	return
@@ -739,6 +741,15 @@ func (ir *IRReader) ReadString() string {
 	return unsafe.String(unsafe.SliceData(p), len(p))
 }
 
+// A RevisionError describes the first [Artifact] in an IR stream claiming a
+// revision not supported by the registered implementation.
+type RevisionError [2]uint64
+
+func (e RevisionError) Error() string {
+	return "claimed revision " + strconv.FormatUint(e[0], 10) +
+		" differs from implementation value " + strconv.FormatUint(e[1], 10)
+}
+
 // decode decodes the next [Artifact] in the IR stream and returns any buffer
 // originating from [Cache] before returning. decode returns [io.EOF] if and
 // only if the underlying [io.Reader] is already read to EOF.
@@ -771,6 +782,9 @@ func (d *IRDecoder) decode() (a Artifact, err error) {
 		return
 	}
 
+	ir.mustRead(ir.buf[:])
+	rev := binary.LittleEndian.Uint64(ir.buf[:])
+
 	defer ir.putAll()
 	ir.mustRead(ir.buf[:])
 	sz := binary.LittleEndian.Uint64(ir.buf[:])
@@ -778,11 +792,11 @@ func (d *IRDecoder) decode() (a Artifact, err error) {
 		err = ErrIRDepend
 		return
 	}
-	ir.deps = make([]*extIdent, sz)
+	ir.inputs = make([]*extIdent, sz)
-	for i := range ir.deps {
+	for i := range ir.inputs {
-		ir.deps[i] = d.c.getIdentBuf()
+		ir.inputs[i] = d.c.getIdentBuf()
 	}
-	for _, buf := range ir.deps {
+	for _, buf := range ir.inputs {
 		ir.mustRead(buf[:])
 	}
 
@@ -791,6 +805,10 @@ func (d *IRDecoder) decode() (a Artifact, err error) {
 		err = syscall.ENOTRECOVERABLE
 		return
 	}
+	if _rev := GetRevision(a); _rev != rev {
+		err = RevisionError{rev, _rev}
+		return
+	}
 
 	if ir.count != -1 {
 		err = ErrRemainingIR

internal/pkg/ir_test.go

@@ -135,3 +135,36 @@ func TestIRRoundtrip(t *testing.T) {
 	}
 	checkWithCache(t, testCasesCache)
 }
+
+func TestRevision(t *testing.T) {
+	checkWithCache(t, []cacheTestCase{{"revision", 0, nil,
+		func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
+			a := pkg.NewFile("", nil)
+			var buf bytes.Buffer
+			if err := c.EncodeAll(&buf, a); err != nil {
+				t.Fatal(err)
+			}
+
+			if _, err := c.NewDecoder(
+				bytes.NewReader(buf.Bytes()),
+			).Decode(); err != nil {
+				t.Fatalf("Decode: error = %v", err)
+			}
+
+			p := buf.Bytes()
+			p[8] = 0xfd
+			wantErr := pkg.RevisionError{0xfd, 0}
+			if _, err := c.NewDecoder(
+				bytes.NewReader(p),
+			).Decode(); !reflect.DeepEqual(err, wantErr) {
+				t.Fatalf("Decode: error = %v, want %v", err, wantErr)
+			}
+		}, expectsFS{
+			".":          {Mode: fs.ModeDir | 0700},
+			"checksum":   {Mode: fs.ModeDir | 0700},
+			"identifier": {Mode: fs.ModeDir | 0700},
+			"substitute": {Mode: fs.ModeDir | 0700},
+			"work":       {Mode: fs.ModeDir | 0700},
+		},
+	}})
+}

internal/pkg/net.go

@@ -54,8 +54,8 @@ func init() {
 	})
 }
 
-// Dependencies returns a nil slice.
+// Inputs returns a nil slice.
-func (*httpArtifact) Dependencies() []Artifact { return nil }
+func (*httpArtifact) Inputs() []Artifact { return nil }
 
 // IsExclusive returns false: Cure returns as soon as a response is received.
 func (*httpArtifact) IsExclusive() bool { return false }
@@ -74,6 +74,9 @@ func (e ResponseStatusError) Error() string {
 	return "the requested URL returned non-OK status: " + http.StatusText(int(e))
 }
 
+// IsExecutable returns false.
+func (*httpArtifact) IsExecutable() bool { return false }
+
 // Cure sends the http request and returns the resulting response body reader
 // wrapped to perform checksum validation. It is valid but not encouraged to
 // close the resulting [io.ReadCloser] before it is read to EOF, as that causes

internal/pkg/net_test.go

@@ -104,7 +104,7 @@ func TestHTTPGet(t *testing.T) {
 			)
 			wantPathname := base.Append(
 				"identifier",
-				"oM-2pUlk-mOxK1t3aMWZer69UdOQlAXiAgMrpZ1476VoOqpYVP1aGFS9_HYy-D8_",
+				"COBRUwkxpIvZWJggpRxn7HVXiw6epXZOex8jGRJKpowpwukV7GRBY_LBvOJNQHue",
 			)
 			if pathname, checksum, err := c.Cure(f); err != nil {
 				t.Fatalf("Cure: error = %v", err)
@@ -158,7 +158,7 @@ func TestHTTPGet(t *testing.T) {
 			"checksum/fLYGIMHgN1louE-JzITJZJo2SDniPu-IHBXubtvQWFO-hXnDVKNuscV7-zlyr5fU": {Mode: 0400, Data: []byte("\x7f\xe1\x69\xa2\xdd\x63\x96\x26\x83\x79\x61\x8b\xf0\x3f\xd5\x16\x9a\x39\x3a\xdb\xcf\xb1\xbc\x8d\x33\xff\x75\xee\x62\x56\xa9\xf0\x27\xac\x13\x94\x69")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/oM-2pUlk-mOxK1t3aMWZer69UdOQlAXiAgMrpZ1476VoOqpYVP1aGFS9_HYy-D8_": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fLYGIMHgN1louE-JzITJZJo2SDniPu-IHBXubtvQWFO-hXnDVKNuscV7-zlyr5fU")},
+			"identifier/COBRUwkxpIvZWJggpRxn7HVXiw6epXZOex8jGRJKpowpwukV7GRBY_LBvOJNQHue": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fLYGIMHgN1louE-JzITJZJo2SDniPu-IHBXubtvQWFO-hXnDVKNuscV7-zlyr5fU")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 

internal/pkg/pkg.go

@@ -6,6 +6,7 @@ import (
 	"bytes"
 	"cmp"
 	"context"
+	"crypto/rand"
 	"crypto/sha512"
 	"encoding/base64"
 	"encoding/binary"
@@ -15,6 +16,7 @@ import (
 	"io"
 	"io/fs"
 	"maps"
+	"math"
 	"os"
 	"os/signal"
 	"path/filepath"
@@ -278,7 +280,11 @@ func (c *common) GetMessage() message.Msg { return c.cache.msg }
 
 // GetJobs returns the preferred number of jobs to run, when applicable. Its
 // value must not affect cure outcome.
-func (c *common) GetJobs() int { return c.cache.jobs }
+func (c *common) GetJobs() int { return c.cache.attr.Jobs }
+
+// GetLoad returns the preferred load average target, when applicable. Its
+// value must not affect cure outcome.
+func (c *common) GetLoad() int { return c.cache.attr.Load }
 
 // GetWorkDir returns a pathname to a directory which [Artifact] is expected to
 // write its output to. This is not the final resting place of the [Artifact]
@@ -303,7 +309,7 @@ func (c *common) Open(a Artifact) (r io.ReadCloser, err error) {
 	}
 
 	var pathname *check.Absolute
-	if pathname, _, err = c.cache.cure(a, true); err != nil {
+	if pathname, _, _, err = c.cache.cure(a, true, false); err != nil {
 		return
 	}
 
@@ -330,8 +336,8 @@ func (c *common) Open(a Artifact) (r io.ReadCloser, err error) {
 type FContext struct {
 	TContext
 
-	// Cured top-level dependencies looked up by Pathname.
+	// Cured top-level inputs looked up by Pathname.
-	deps map[Artifact]cureRes
+	inputs map[Artifact]cureRes
 }
 
 // linkSubstitute links status for substitute if populated.
@@ -356,24 +362,24 @@ func (f *FContext) linkSubstitute(ids, substitutes string) (err error) {
 	return
 }
 
-// InvalidLookupError is the identifier of non-dependency [Artifact] looked up
+// InvalidLookupError is the identifier of non-input [Artifact] looked up
 // via [FContext.GetArtifact] by a misbehaving [Artifact] implementation.
 type InvalidLookupError ID
 
 func (e InvalidLookupError) Error() string {
-	return "attempting to look up non-dependency artifact " + Encode(e)
+	return "attempting to look up non-input artifact " + Encode(e)
 }
 
 var _ error = InvalidLookupError{}
 
 // GetArtifact returns the identifier pathname and checksum of an [Artifact].
 // Calling Pathname with an [Artifact] not part of the slice returned by
-// [Artifact.Dependencies] panics.
+// [Artifact.Inputs] panics.
 func (f *FContext) GetArtifact(a Artifact) (
 	pathname *check.Absolute,
 	checksum unique.Handle[Checksum],
 ) {
-	if res, ok := f.deps[a]; ok {
+	if res, ok := f.inputs[a]; ok {
 		return res.pathname, res.checksum
 	}
 	panic(InvalidLookupError(f.cache.Ident(a).Value()))
@@ -405,13 +411,13 @@ type Artifact interface {
 	// Result must remain identical across multiple invocations.
 	Params(ctx *IContext)
 
-	// Dependencies returns a slice of [Artifact] that the current instance
+	// Inputs returns a slice of [Artifact] the current instance has access to
-	// depends on to produce its contents.
+	// while producing its output.
 	//
 	// Callers must not modify the retuned slice.
 	//
 	// Result must remain identical across multiple invocations.
-	Dependencies() []Artifact
+	Inputs() []Artifact
 
 	// IsExclusive returns whether the [Artifact] is exclusive. Exclusive
 	// artifacts might not run in parallel with each other, and are still
@@ -472,6 +478,8 @@ type KnownIdent interface {
 	// [Artifact]. This value must be known ahead of time and guaranteed to be
 	// unique without having obtained the full contents of the [Artifact].
 	ID() ID
+
+	Artifact
 }
 
 // KnownChecksum is optionally implemented by [Artifact] for an artifact with
@@ -483,6 +491,18 @@ type KnownChecksum interface {
 	//
 	// Result must remain identical across multiple invocations.
 	Checksum() Checksum
+
+	Artifact
+}
+
+// CuresExempt is optionally implemented for an artifact exempt to the
+// cache-wide cures counter and limit.
+type CuresExempt interface {
+	Artifact
+
+	// CuresExempt is a no-op function but serves to distinguish implementations
+	// that are cures-exempt.
+	CuresExempt()
 }
 
 // FileArtifact refers to an [Artifact] backed by a single file.
@@ -490,6 +510,12 @@ type KnownChecksum interface {
 // FileArtifact does not support fine-grained cancellation. Its context is
 // inherited from the first [TrivialArtifact] or [FloodArtifact] that opens it.
 type FileArtifact interface {
+	// IsExecutable returns whether the resulting filesystem entry should be made
+	// executable, if the [FileArtifact] is cured to the on-disk cache.
+	//
+	// Result must remain identical across multiple invocations.
+	IsExecutable() bool
+
 	// Cure returns [io.ReadCloser] of the full contents of [FileArtifact]. If
 	// [FileArtifact] implements [KnownChecksum], Cure is responsible for
 	// validating any data it produces and must return [ChecksumMismatchError]
@@ -499,12 +525,35 @@ type FileArtifact interface {
 	//
 	// Callers are responsible for closing the resulting [io.ReadCloser].
 	//
-	// Result must remain identical across multiple invocations.
+	// The resulting [io.ReadCloser] across multiple invocations must have
+	// identical behaviour.
 	Cure(r *RContext) (io.ReadCloser, error)
 
 	Artifact
 }
 
+// RevisionArtifact is optionally implemented by an artifact that had undergone
+// internal changes affecting its behaviour while retaining its IR structure.
+type RevisionArtifact interface {
+	// Revision returns the revision number of [Artifact]. This value is always
+	// represented in the IR. An IR stream produced from the same [Kind] with
+	// differing revision is rejected.
+	//
+	// Result must remain identical across multiple invocations.
+	Revision() uint64
+
+	Artifact
+}
+
+// GetRevision returns the revision number of an [Artifact].
+func GetRevision(a Artifact) (revision uint64) {
+	revision = math.MaxUint64
+	if r, ok := a.(RevisionArtifact); ok {
+		revision = r.Revision()
+	}
+	return
+}
+
 // reportName returns a string describing [Artifact] presented to the user.
 func reportName(a Artifact, id unique.Handle[ID]) string {
 	r := Encode(id.Value())
@@ -592,7 +641,7 @@ type cureRes struct {
 	checksum unique.Handle[Checksum]
 }
 
-// A pendingArtifactDep is a dependency [Artifact] pending concurrent curing,
+// A pendingArtifactDep is an input [Artifact] pending concurrent curing,
 // subject to the cures limit. Values pointed to by result addresses are safe
 // to access after the [sync.WaitGroup] associated with this pendingArtifactDep
 // is done. pendingArtifactDep must not be reused or modified after it is sent
@@ -666,8 +715,12 @@ const (
 	// suppressed regardless of [message.Msg] state.
 	CSuppressInit
 
-	// CIgnoreSubstitutes disables content-based dependency substitution.
+	// CIgnoreSubstitutes disables content-based input substitution.
 	CIgnoreSubstitutes
+
+	// CExternShallow arranges for only non-flood inputs to be fetched when
+	// curing an [Artifact] available via the external cache.
+	CExternShallow
 )
 
 // toplevel holds [context.WithCancel] over caller-supplied context, where all
@@ -719,17 +772,15 @@ type Cache struct {
 	parent context.Context
 	// For deriving curing context, must not be accessed directly.
 	toplevel atomic.Pointer[toplevel]
-	// For waiting on dependency curing goroutines.
+	// For waiting on input curing goroutines.
 	wg sync.WaitGroup
 	// Reports new cures and passed to [Artifact].
 	msg message.Msg
 
 	// Directory where all [Cache] related files are placed.
 	base *check.Absolute
-	// Immutable cure options set by [Open].
+	// Immutable [CacheAttr] populated by [Open].
-	flags int
+	attr CacheAttr
-	// Immutable job count, when applicable.
-	jobs int
 
 	// Must not be exposed directly.
 	irCache
@@ -760,6 +811,8 @@ type Cache struct {
 
 	// Optional external cache implementation.
 	extern External
+	// Caches responses from extern.
+	externCache map[unique.Handle[ID]]unique.Handle[Checksum]
 	// Synchronises access to extern.
 	externMu sync.RWMutex
 
@@ -920,6 +973,7 @@ func readlinkChecksum(a *check.Absolute, buf *Checksum) error {
 // SetExternal sets e as the [External] implementation of c.
 func (c *Cache) SetExternal(e External) {
 	c.externMu.Lock()
+	c.externCache = make(map[unique.Handle[ID]]unique.Handle[Checksum])
 	c.extern = e
 	c.externMu.Unlock()
 }
@@ -1431,7 +1485,7 @@ func (c *Cache) openFile(
 	ctx context.Context,
 	f FileArtifact,
 ) (r io.ReadCloser, err error) {
-	if kc, ok := f.(KnownChecksum); c.flags&CAssumeChecksum != 0 && ok {
+	if kc, ok := f.(KnownChecksum); c.attr.Flags&CAssumeChecksum != 0 && ok {
 		c.checksumMu.RLock()
 		r, err = os.Open(c.base.Append(
 			dirChecksum,
@@ -1616,7 +1670,47 @@ func (c *Cache) Cure(a Artifact) (
 		return
 	}
 
-	return c.cure(a, true)
+	pathname, checksum, _, err = c.cure(a, true, false)
+	return
+}
+
+// CureWhence is like Cure, but returns the whence value.
+func (c *Cache) CureWhence(a Artifact) (
+	pathname *check.Absolute,
+	checksum unique.Handle[Checksum],
+	whence int,
+	err error,
+) {
+	c.abortMu.RLock()
+	defer c.abortMu.RUnlock()
+
+	if err = c.toplevel.Load().ctx.Err(); err != nil {
+		return
+	}
+
+	return c.cure(a, true, false)
+}
+
+// CureNew is like Cure, but always enters the implementation.
+func (c *Cache) CureNew(a Artifact) (
+	pathname *check.Absolute,
+	checksum unique.Handle[Checksum],
+	err error,
+) {
+	c.abortMu.RLock()
+	defer c.abortMu.RUnlock()
+
+	if err = c.toplevel.Load().ctx.Err(); err != nil {
+		return
+	}
+
+	var whence int
+retry:
+	pathname, checksum, whence, err = c.cure(a, true, true)
+	if err != nil || whence == WNew {
+		return
+	}
+	goto retry
 }
 
 // CureError wraps a non-nil error returned attempting to cure an [Artifact].
@@ -1838,71 +1932,11 @@ func (r *RContext) NewMeasuredReader(
 	return r.cache.newMeasuredReader(rc, checksum)
 }
 
-// tryExtern attempts to obtain an [Artifact] outcome from extern.
+// tryChecksum dereferences a symlink to a cure outcome.
-func (c *Cache) tryExtern(ctx context.Context, id unique.Handle[ID]) (
+func (c *Cache) tryChecksum(pathname *check.Absolute) (
-	unique.Handle[Checksum],
-	io.ReadCloser,
-	error,
-) {
-	c.externMu.RLock()
-	defer c.externMu.RUnlock()
-
-	if c.extern == nil {
-		return zeroChecksum, nil, nil
-	}
-
-	v, err := c.extern.Artifact(ctx, id)
-	if err != nil {
-		return zeroChecksum, nil, err
-	}
-	if v == nil {
-		return zeroChecksum, nil, nil
-	}
-	checksum := unique.Make(*v)
-
-	var got unique.Handle[Checksum]
-	if _, got, err = c.Cure(c.extern.Checksum(checksum)); err != nil {
-		return checksum, nil, err
-	} else if got != checksum {
-		return zeroChecksum, nil, &ChecksumMismatchError{got.Value(), checksum.Value()}
-	}
-
-	var status io.ReadCloser
-	status, err = c.extern.Status(&RContext{common{ctx, c}}, id)
-	return checksum, status, err
-}
-
-// cure implements Cure without acquiring a read lock on abortMu. cure must not
-// be entered during Abort.
-func (c *Cache) cure(a Artifact, curesExempt bool) (
-	pathname *check.Absolute,
 	checksum unique.Handle[Checksum],
 	err error,
 ) {
-	id := c.Ident(a)
-	ids := Encode(id.Value())
-	pathname = c.base.Append(
-		dirIdentifier,
-		ids,
-	)
-	defer func() {
-		if err != nil {
-			pathname = nil
-			checksum = unique.Handle[Checksum]{}
-		}
-	}()
-
-	var (
-		ctx  context.Context
-		done chan<- struct{}
-	)
-	ctx, done, checksum, err = c.loadOrStoreIdent(id)
-	if done == nil {
-		return
-	} else {
-		defer func() { c.finaliseIdent(done, id, checksum, err) }()
-	}
-
 	_, err = os.Lstat(pathname.String())
 	if err == nil {
 		var name string
@@ -1915,9 +1949,180 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 			checksum = unique.Make(Checksum(buf[:]))
 		}
 		c.putIdentBuf(buf)
+	}
 	return
 }
-	if !errors.Is(err, os.ErrNotExist) {
+
+// tryLocal attempts to obtain an [Artifact] outcome from the filesystem.
+func (c *Cache) tryLocal(id unique.Handle[ID]) (unique.Handle[Checksum], error) {
+	return c.tryChecksum(c.base.Append(
+		dirIdentifier,
+		Encode(id.Value()),
+	))
+}
+
+// tryExtern attempts to obtain an [Artifact] outcome from extern.
+func (c *Cache) tryExtern(ctx context.Context, id unique.Handle[ID]) (
+	unique.Handle[Checksum],
+	error,
+) {
+	c.externMu.RLock()
+	defer c.externMu.RUnlock()
+
+	checksum, ok := c.externCache[id]
+	if !ok {
+		if c.extern == nil {
+			return zeroChecksum, nil
+		}
+
+		v, err := c.extern.Artifact(ctx, id)
+		if err != nil {
+			return zeroChecksum, err
+		}
+		if v == nil {
+			return zeroChecksum, nil
+		}
+		checksum = unique.Make(*v)
+
+		var got unique.Handle[Checksum]
+		if _, got, err = c.Cure(c.extern.Checksum(checksum)); err != nil {
+			return checksum, err
+		} else if got != checksum {
+			return zeroChecksum, &ChecksumMismatchError{got.Value(), checksum.Value()}
+		}
+	}
+	return checksum, nil
+}
+
+// cureMany concurrently collects outcome of multiple [Artifact].
+func (c *Cache) cureMany(
+	inputs []Artifact,
+	r map[Artifact]cureRes,
+	shallow bool,
+) ([]bool, error) {
+	var wg sync.WaitGroup
+	wg.Add(len(inputs))
+	var mask []bool
+	res := make([]cureRes, len(inputs))
+	errs := make(DependencyCureError, 0, len(inputs))
+	var errsMu sync.Mutex
+	if shallow {
+		mask = make([]bool, len(inputs))
+	}
+	for i, d := range inputs {
+		if shallow {
+			if _, ok := d.(FloodArtifact); ok {
+				mask[i] = true
+				wg.Done()
+				continue
+			}
+
+			if kc, ok := d.(KnownChecksum); ok {
+				res[i].checksum = unique.Make(kc.Checksum())
+				wg.Done()
+				continue
+			}
+		}
+		pending := pendingArtifactDep{d, &res[i], &errs, &errsMu, &wg}
+		go pending.cure(c)
+	}
+	wg.Wait()
+
+	if len(errs) > 0 {
+		return mask, &errs
+	}
+	for i, p := range res {
+		if shallow && mask[i] {
+			continue
+		}
+		r[inputs[i]] = p
+	}
+	return mask, nil
+}
+
+// HangingInputError describes an input of an [Artifact] on a sparse cache
+// without an outcome available locally or via [External].
+type HangingInputError unique.Handle[ID]
+
+func (e HangingInputError) Error() string {
+	return Encode(unique.Handle[ID](e).Value()) + " is unavailable"
+}
+
+const (
+	// WNew indicates a cure entering the implementation.
+	WNew = iota
+	// WCache indicates an [Artifact] present in the cache.
+	WCache
+	// WSubstitute indicates an [Artifact] hitting a content-based input
+	// substitution.
+	WSubstitute
+	// WExternal indicates a cure entering the external cache.
+	WExternal
+)
+
+// WhenceString returns a printable string for a whence value.
+func WhenceString(whence int) string {
+	switch whence {
+	case WNew:
+		return "new"
+	case WCache:
+		return "cache"
+	case WSubstitute:
+		return "substitute"
+	case WExternal:
+		return "external"
+
+	default:
+		return "invalid whence " + strconv.Itoa(whence)
+	}
+}
+
+// cure implements Cure without acquiring a read lock on abortMu. cure must not
+// be entered during Abort.
+func (c *Cache) cure(a Artifact, curesExempt, rebuild bool) (
+	pathname *check.Absolute,
+	checksum unique.Handle[Checksum],
+	whence int,
+	err error,
+) {
+	id := c.Ident(a)
+	if rebuild {
+		var v ID
+		_, _ = rand.Read(v[:])
+		id = unique.Make(v)
+	}
+
+	ids := Encode(id.Value())
+	pathname = c.base.Append(
+		dirIdentifier,
+		ids,
+	)
+	defer func() {
+		if err != nil {
+			pathname = nil
+			checksum = unique.Handle[Checksum]{}
+		}
+	}()
+
+	if _, ok := a.(CuresExempt); ok {
+		curesExempt = true
+	}
+
+	var (
+		ctx  context.Context
+		done chan<- struct{}
+	)
+	ctx, done, checksum, err = c.loadOrStoreIdent(id)
+	if done == nil {
+		whence = WCache
+		return
+	} else {
+		defer func() { c.finaliseIdent(done, id, checksum, err) }()
+	}
+
+	checksum, err = c.tryChecksum(pathname)
+	if err == nil || !errors.Is(err, os.ErrNotExist) {
+		whence = WCache
 		return
 	}
 
@@ -1972,7 +2177,7 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 			checksums,
 		)
 
-		if c.flags&CAssumeChecksum != 0 {
+		if c.attr.Flags&CAssumeChecksum != 0 {
 			c.checksumMu.RLock()
 			checksumFi, err = os.Stat(checksumPathname.String())
 			c.checksumMu.RUnlock()
@@ -1987,6 +2192,7 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 		}
 	}
 
+	whence = WNew
 	if c.msg.IsVerbose() {
 		rn := reportName(a, id)
 		c.msg.Verbosef("curing %s...", rn)
@@ -2005,6 +2211,7 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 	// cure FileArtifact outside type switch to skip TContext initialisation
 	if f, ok := a.(FileArtifact); ok {
 		if checksumFi != nil {
+			whence = WCache
 			if !checksumFi.Mode().IsRegular() {
 				// unreachable
 				err = InvalidFileModeError(checksumFi.Mode())
@@ -2012,12 +2219,17 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 			return
 		}
 
+		perm := os.FileMode(0400)
+		if f.IsExecutable() {
+			perm = 0500
+		}
+
 		work := c.base.Append(dirWork, ids)
 		var w *os.File
 		if w, err = os.OpenFile(
 			work.String(),
 			os.O_CREATE|os.O_EXCL|os.O_WRONLY,
-			0400,
+			perm,
 		); err != nil {
 			return
 		}
@@ -2039,7 +2251,7 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 		}
 		r, err = f.Cure(&RContext{common{ctx, c}})
 		if err == nil {
-			if checksumPathname == nil || c.flags&CValidateKnown != 0 {
+			if checksumPathname == nil || c.attr.Flags&CValidateKnown != 0 {
 				h := sha512.New384()
 				hbw := c.getWriter(h)
 				_, err = io.Copy(w, io.TeeReader(r, hbw))
@@ -2056,7 +2268,7 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 					if checksumPathname == nil {
 						checksum = unique.Make(Checksum(buf[:]))
 						checksums = Encode(Checksum(buf[:]))
-					} else if c.flags&CValidateKnown != 0 {
+					} else if c.attr.Flags&CValidateKnown != 0 {
 						if got := Checksum(buf[:]); got != checksum.Value() {
 							err = &ChecksumMismatchError{
 								Got:  got,
@@ -2109,6 +2321,7 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 	}
 
 	if checksumFi != nil {
+		whence = WCache
 		if !checksumFi.Mode().IsDir() {
 			// unreachable
 			err = InvalidFileModeError(checksumFi.Mode())
@@ -2139,30 +2352,64 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 		break
 
 	case FloodArtifact:
-		deps := a.Dependencies()
+		var externChecksum unique.Handle[Checksum]
-		f := FContext{t, make(map[Artifact]cureRes, len(deps))}
+		if externChecksum, err = c.tryExtern(ctx, id); err != nil {
-
+			if c.msg.IsVerbose() {
-		var wg sync.WaitGroup
+				c.msg.Verbosef("extern %s: %v", reportName(ca, id), err)
-		wg.Add(len(deps))
-		res := make([]cureRes, len(deps))
-		errs := make(DependencyCureError, 0, len(deps))
-		var errsMu sync.Mutex
-		for i, d := range deps {
-			pending := pendingArtifactDep{d, &res[i], &errs, &errsMu, &wg}
-			go pending.cure(c)
 			}
-		wg.Wait()
-
-		if len(errs) > 0 {
-			err = &errs
 			return
 		}
-		for i, p := range res {
+		extern := externChecksum != zeroChecksum
-			f.deps[deps[i]] = p
+		shallow := extern && c.attr.Flags&CExternShallow != 0
+
+		inputs := a.Inputs()
+		f := FContext{t, make(map[Artifact]cureRes, len(inputs))}
+		var mask []bool
+		if mask, err = c.cureMany(inputs, f.inputs, shallow); err != nil {
+			return
+		}
+
+		if shallow {
+			for i, d := range inputs {
+				if !mask[i] {
+					continue
+				}
+
+				if kc, ok := d.(KnownChecksum); ok {
+					f.inputs[d] = cureRes{checksum: unique.Make(kc.Checksum())}
+					continue
+				}
+
+				var sum unique.Handle[Checksum]
+				did := c.Ident(d)
+				sum, err = c.tryLocal(did)
+				if err != nil {
+					if !errors.Is(err, os.ErrNotExist) {
+						return
+					}
+
+					sum, err = c.tryExtern(ctx, did)
+					if err != nil {
+						return
+					}
+					if sum == zeroChecksum {
+						if c.msg.IsVerbose() {
+							c.msg.Verbosef(
+								"input %s not available",
+								reportName(d, did),
+							)
+						}
+						err = HangingInputError(did)
+						return
+					}
+				}
+
+				f.inputs[d] = cureRes{checksum: sum}
+			}
 		}
 
 		sh := sha512.New384()
-		err = c.encode(sh, a, f.deps)
+		err = c.encode(sh, a, f.inputs)
 		if err != nil {
 			return
 		}
@@ -2177,13 +2424,14 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 			substitutes,
 		)
 
-		if c.flags&CIgnoreSubstitutes == 0 {
+		if !rebuild && c.attr.Flags&CIgnoreSubstitutes == 0 {
 			var substituteChecksum unique.Handle[Checksum]
 			substituteChecksum, err = c.loadSubstitute(substitute)
 			if err != nil {
 				return
 			}
 			if substituteChecksum != zeroChecksum {
+				whence = WSubstitute
 				checksum = substituteChecksum
 				checksums = Encode(checksum.Value())
 				checksumPathname = c.base.Append(
@@ -2207,25 +2455,21 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 
 		defer f.destroy(&err)
 
-		var (
+		if extern {
-			externChecksum unique.Handle[Checksum]
+			whence = WExternal
-			externStatus   io.ReadCloser
+			if checksum != zeroChecksum && externChecksum != checksum {
-		)
+				err = &ChecksumMismatchError{externChecksum.Value(), checksum.Value()}
-		if externChecksum, externStatus, err = c.tryExtern(ctx, id); err != nil {
 				if c.msg.IsVerbose() {
 					c.msg.Verbosef("extern %s: %v", reportName(ca, id), err)
 				}
 				return
 			}
-		if externChecksum != zeroChecksum {
+
-			if checksum != zeroChecksum && externChecksum != checksum {
+			var externStatus io.ReadCloser
-				if externStatus != nil {
+			c.externMu.RLock()
-					_ = externStatus.Close()
+			externStatus, err = c.extern.Status(&RContext{common{ctx, c}}, id)
-				}
+			c.externMu.RUnlock()
-				err = &ChecksumMismatchError{externChecksum.Value(), checksum.Value()}
+			if err != nil {
-				if c.msg.IsVerbose() {
-					c.msg.Verbosef("extern %s: %v", reportName(ca, id), err)
-				}
 				return
 			}
 
@@ -2245,10 +2489,12 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 					return
 				} else if err = externStatus.Close(); err != nil {
 					return
-				} else if err = f.linkSubstitute(ids, substitutes); err != nil {
+				} else if !rebuild {
+					if err = f.linkSubstitute(ids, substitutes); err != nil {
 						return
 					}
 				}
+			}
 			return
 		}
 
@@ -2258,7 +2504,7 @@ func (c *Cache) cure(a Artifact, curesExempt bool) (
 		err = ca.Cure(&f)
 		c.exitCure(a, curesExempt)
 
-		if err == nil {
+		if !rebuild && err == nil {
 			err = f.linkSubstitute(ids, substitutes)
 		}
 		if err != nil {
@@ -2352,7 +2598,7 @@ func (pending *pendingArtifactDep) cure(c *Cache) {
 	defer pending.Done()
 
 	var err error
-	pending.resP.pathname, pending.resP.checksum, err = c.cure(pending.a, false)
+	pending.resP.pathname, pending.resP.checksum, _, err = c.cure(pending.a, false, false)
 	if err == nil {
 		return
 	}
@@ -2472,6 +2718,22 @@ var (
 	ErrWouldPromote = errors.New("operation would promote unextended cache")
 )
 
+// CacheAttr holds the attributes that will be applied to a new [Cache] opened
+// by [Open].
+type CacheAttr struct {
+	// Concurrent cures of a [FloodArtifact] dependency graph.
+	Cures int
+	// Options affecting [Cache] behaviour.
+	Flags int
+	// Preferred job count, when applicable.
+	Jobs int
+	// Preferred loadavg target, when applicable.
+	Load int
+
+	// Omit the [lockedfile] lock.
+	skipLock bool
+}
+
 // Open returns the address of a newly opened instance of [Cache].
 //
 // Concurrent cures of a [FloodArtifact] dependency graph is limited to the
@@ -2488,20 +2750,8 @@ var (
 func Open(
 	ctx context.Context,
 	msg message.Msg,
-	flags, cures, jobs int,
 	base *check.Absolute,
-) (*Cache, error) {
+	attr *CacheAttr,
-	return open(ctx, msg, flags, cures, jobs, base, true)
-}
-
-// open implements Open but allows omitting the [lockedfile] lock when called
-// from a test. This is used to simulate invalid states in the test suite.
-func open(
-	ctx context.Context,
-	msg message.Msg,
-	flags, cures, jobs int,
-	base *check.Absolute,
-	lock bool,
 ) (*Cache, error) {
 	openMu.Lock()
 	defer openMu.Unlock()
@@ -2511,11 +2761,19 @@ func open(
 		panic("attempting to open cache with incomplete variant setup")
 	}
 
-	if cures < 1 {
+	var a CacheAttr
-		cures = runtime.NumCPU()
+	if attr != nil {
+		a = *attr
 	}
-	if jobs < 1 {
+
-		jobs = runtime.NumCPU()
+	if a.Cures < 1 {
+		a.Cures = runtime.NumCPU()
+	}
+	if a.Jobs < 1 {
+		a.Jobs = runtime.NumCPU()
+	}
+	if a.Load < 1 {
+		a.Load = runtime.NumCPU() + 2
 	}
 
 	for _, name := range []string{
@@ -2537,9 +2795,8 @@ func open(
 	c := Cache{
 		parent: ctx,
 
-		cures: make(chan struct{}, cures),
+		cures: make(chan struct{}, a.Cures),
-		flags: flags,
+		attr:  a,
-		jobs:  jobs,
 
 		msg:  msg,
 		base: base,
@@ -2556,7 +2813,7 @@ func open(
 	}
 	c.toplevel.Store(newToplevel(ctx))
 
-	if lock || !testing.Testing() {
+	if !a.skipLock || !testing.Testing() {
 		if unlock, err := lockedfile.MutexAt(
 			base.Append(fileLock).String(),
 		).Lock(); err != nil {
@@ -2617,7 +2874,7 @@ func open(
 		}
 	} else if s := string(p); s == "" {
 		if extension != "" {
-			if flags&CPromoteVariant == 0 {
+			if a.Flags&CPromoteVariant == 0 {
 				c.unlock()
 				return nil, ErrWouldPromote
 			}
@@ -2656,6 +2913,8 @@ func IsCollected(err error) bool { return errors.As(err, new(Collected)) }
 // [pkg.Artifact]. It returns [Collected].
 type Collect []Artifact
 
+var _ Artifact = new(Collect)
+
 // Cure returns [Collected].
 func (*Collect) Cure(*FContext) error { return Collected{} }
 
@@ -2665,8 +2924,8 @@ func (*Collect) Kind() Kind { return kindCollection }
 // Params is a noop: dependencies are already represented in the header.
 func (*Collect) Params(*IContext) {}
 
-// Dependencies returns [Collect] as is.
+// Inputs returns [Collect] as is.
-func (c *Collect) Dependencies() []Artifact { return *c }
+func (c *Collect) Inputs() []Artifact { return *c }
 
 // IsExclusive returns false: Cure is a noop.
 func (*Collect) IsExclusive() bool { return false }

internal/pkg/pkg_test.go

@@ -35,14 +35,14 @@ import (
 	"hakurei.app/message"
 )
 
-//go:linkname unsafeOpen hakurei.app/internal/pkg.open
+var skipLock = func() pkg.CacheAttr {
-func unsafeOpen(
+	var attr pkg.CacheAttr
-	ctx context.Context,
+	*(*bool)(unsafe.Pointer(reflect.ValueOf(&attr).
-	msg message.Msg,
+		Elem().
-	flags, cures, jobs int,
+		FieldByName("skipLock").
-	base *check.Absolute,
+		UnsafeAddr())) = true
-	lock bool,
+	return attr
-) (*pkg.Cache, error)
+}()
 
 var (
 	// extension is a string uniquely identifying a set of custom [Artifact]
@@ -142,7 +142,7 @@ type stubArtifact struct {
 
 func (a *stubArtifact) Kind() pkg.Kind             { return a.kind }
 func (a *stubArtifact) Params(ctx *pkg.IContext)   { ctx.Write(a.params) }
-func (a *stubArtifact) Dependencies() []pkg.Artifact { return a.deps }
+func (a *stubArtifact) Inputs() []pkg.Artifact     { return a.deps }
 func (a *stubArtifact) Cure(t *pkg.TContext) error { return a.cure(t) }
 func (*stubArtifact) IsExclusive() bool            { return false }
 
@@ -158,7 +158,7 @@ type stubArtifactF struct {
 
 func (a *stubArtifactF) Kind() pkg.Kind             { return a.kind }
 func (a *stubArtifactF) Params(ctx *pkg.IContext)   { ctx.Write(a.params) }
-func (a *stubArtifactF) Dependencies() []pkg.Artifact { return a.deps }
+func (a *stubArtifactF) Inputs() []pkg.Artifact     { return a.deps }
 func (a *stubArtifactF) Cure(f *pkg.FContext) error { return a.cure(f) }
 func (a *stubArtifactF) IsExclusive() bool          { return a.excl }
 
@@ -170,6 +170,8 @@ type stubFile struct {
 	stubArtifact
 }
 
+func (*stubFile) IsExecutable() bool { return false }
+
 func (a *stubFile) Cure(*pkg.RContext) (io.ReadCloser, error) {
 	return io.NopCloser(bytes.NewReader(a.data)), a.err
 }
@@ -330,7 +332,7 @@ func TestIdent(t *testing.T) {
 			},
 			nil,
 		}, unique.Make[pkg.ID](pkg.MustDecode(
-			"97Y85QewssfPbNIN9cyNhzD4e6dLHcDTU8rb2c34k-aCrZfBNXFUc0duPiLFFcw_",
+			"fkmge-H56Ph2LzNNbEUjTypes8LfOxrF_CEXg07kq6ho_nbTNvzQde9-bjB7gyB_",
 		))},
 	}
 
@@ -339,7 +341,7 @@ func TestIdent(t *testing.T) {
 	var cache *pkg.Cache
 	if a, err := check.NewAbs(t.TempDir()); err != nil {
 		t.Fatal(err)
-	} else if cache, err = pkg.Open(t.Context(), msg, 0, 0, 0, a); err != nil {
+	} else if cache, err = pkg.Open(t.Context(), msg, a, nil); err != nil {
 		t.Fatal(err)
 	}
 	t.Cleanup(cache.Close)
@@ -519,7 +521,10 @@ func checkWithCache(t *testing.T, testCases []cacheTestCase) {
 			}
 
 			var scrubFunc func() error // scrub after hashing
-			if c, err := pkg.Open(t.Context(), msg, flags, 1<<4, 0, base); err != nil {
+			if c, err := pkg.Open(t.Context(), msg, base, &pkg.CacheAttr{
+				Cures: 1 << 4,
+				Flags: flags,
+			}); err != nil {
 				t.Fatalf("Open: error = %v", err)
 			} else {
 				t.Cleanup(c.Close)
@@ -627,6 +632,7 @@ type cureStep struct {
 
 	pathname *check.Absolute
 	output   expectsKnown
+	whence   int
 	err      error
 }
 
@@ -646,7 +652,7 @@ func cureMany(t *testing.T, c *pkg.Cache, steps []cureStep) {
 
 	for _, step := range steps {
 		t.Log("cure step:", step.name)
-		if pathname, checksum, err := c.Cure(step.a); !reflect.DeepEqual(err, step.err) {
+		if pathname, checksum, whence, err := c.CureWhence(step.a); !reflect.DeepEqual(err, step.err) {
 			faults, _err := c.ReadFaults(step.a)
 			if _err != nil {
 				t.Errorf("ReadFaults: error = %v", _err)
@@ -663,6 +669,8 @@ func cureMany(t *testing.T, c *pkg.Cache, steps []cureStep) {
 				t.Logf("faulting cure terminated %s ago", time.Since(faults[0].Time()))
 			}
 			t.Fatalf("Cure: error = %v, want %v", err, step.err)
+		} else if step.whence != whence {
+			t.Fatalf("Cure: whence = %s, want %s", pkg.WhenceString(whence), pkg.WhenceString(step.whence))
 		} else if step.pathname != ignorePathname && !pathname.Is(step.pathname) {
 			t.Fatalf("Cure: pathname = %q, want %q", pathname, step.pathname)
 		} else if step.output == nil || checksum != makeChecksumH(step.output.hash()) {
@@ -774,28 +782,28 @@ func TestCache(t *testing.T) {
 					identifier,
 					new(testdata.hash()),
 					testdata, nil,
-				), wantPathname, testdata, nil},
+				), wantPathname, testdata, pkg.WNew, nil},
 
 				{"identical content", newStubFile(
 					pkg.KindHTTPGet,
 					identifier0,
 					new(testdata.hash()),
 					testdata, nil,
-				), wantPathname0, testdata, nil},
+				), wantPathname0, testdata, pkg.WCache, nil},
 
 				{"existing entry", newStubFile(
 					pkg.KindHTTPGet,
 					identifier,
 					new(testdata.hash()),
 					testdata, nil,
-				), wantPathname, testdata, nil},
+				), wantPathname, testdata, pkg.WCache, nil},
 
 				{"checksum mismatch", newStubFile(
 					pkg.KindHTTPGet,
 					pkg.ID{0xff, 0},
 					new(pkg.Checksum),
 					testdata, nil,
-				), nil, nil, &pkg.ChecksumMismatchError{
+				), nil, nil, pkg.WNew, &pkg.ChecksumMismatchError{
 					Got: testdata.hash(),
 				}},
 
@@ -816,13 +824,13 @@ func TestCache(t *testing.T) {
 					0x36, 0x65, 0x59, 0x33, 0xec, 0x2b,
 					0x41, 0x34, 0x65, 0x96, 0x68, 0x17,
 					0xa9, 0xc2, 0x08, 0xa1, 0x17, 0x17,
-				}, nil},
+				}, pkg.WNew, nil},
 
 				{"incomplete implementation", struct{ pkg.Artifact }{&stubArtifact{
 					kind:   pkg.KindExec,
 					params: []byte("artifact overridden to be incomplete"),
-				}}, nil, nil, pkg.InvalidArtifactError(pkg.MustDecode(
+				}}, nil, nil, pkg.WNew, pkg.InvalidArtifactError(pkg.MustDecode(
-					"E__uZ1sLIvb84vzSm5Uezb03RogsiaeTt1nfIVv8TKnnf4LqwtSi-smdHhlkZrUJ",
+					"poVrv3zNINbHd-WUJihwgWQwJpbHURFHfpY7Zux-ztto_bQhhS5PdpbNMjdkXv-V",
 				))},
 
 				{"error passthrough", newStubFile(
@@ -830,18 +838,18 @@ func TestCache(t *testing.T) {
 					pkg.ID{0xff, 1},
 					nil,
 					nil, stub.UniqueError(0xcafe),
-				), nil, nil, stub.UniqueError(0xcafe)},
+				), nil, nil, pkg.WNew, stub.UniqueError(0xcafe)},
 
 				{"error caching", newStubFile(
 					pkg.KindHTTPGet,
 					pkg.ID{0xff, 1},
 					nil,
 					nil, nil,
-				), nil, nil, stub.UniqueError(0xcafe)},
+				), nil, nil, pkg.WCache, stub.UniqueError(0xcafe)},
 
 				{"cache hit bad type", overrideChecksum{testdata.hash(), overrideIdent{pkg.ID{0xff, 2}, &stubArtifact{
 					kind: pkg.KindTar,
-				}}}, nil, nil, pkg.InvalidFileModeError(
+				}}}, nil, nil, pkg.WCache, pkg.InvalidFileModeError(
 					0400,
 				)},
 
@@ -853,7 +861,7 @@ func TestCache(t *testing.T) {
 					cure: func(f *pkg.FContext) error {
 						panic("attempting to cure impossible artifact")
 					},
-				}, nil, nil, &pkg.DependencyCureError{
+				}, nil, nil, pkg.WNew, &pkg.DependencyCureError{
 					{
 						A: failingFile,
 						Err: struct {
@@ -864,10 +872,10 @@ func TestCache(t *testing.T) {
 				}},
 			})
 
-			if c0, err := unsafeOpen(
+			if c0, err := pkg.Open(
 				t.Context(),
 				message.New(nil),
-				0, 0, 0, base, false,
+				base, &skipLock,
 			); err != nil {
 				t.Fatalf("open: error = %v", err)
 			} else {
@@ -875,7 +883,7 @@ func TestCache(t *testing.T) {
 				cureMany(t, c0, []cureStep{
 					{"cache hit ident", overrideIdent{
 						id: identifier,
-					}, wantPathname, testdata, nil},
+					}, wantPathname, testdata, pkg.WCache, nil},
 
 					{"cache miss checksum match", newStubFile(
 						pkg.KindHTTPGet,
@@ -886,7 +894,7 @@ func TestCache(t *testing.T) {
 					), base.Append(
 						"identifier",
 						pkg.Encode(testdata.hash()),
-					), testdata, nil},
+					), testdata, pkg.WNew, nil},
 				})
 
 				// cure after close
@@ -1016,30 +1024,30 @@ func TestCache(t *testing.T) {
 				{"initial directory", overrideChecksum{want.hash(), overrideIdent{id, &stubArtifact{
 					kind: pkg.KindTar,
 					cure: makeSample,
-				}}}, wantPathname, want, nil},
+				}}}, wantPathname, want, pkg.WNew, nil},
 
 				{"identical identifier", overrideChecksum{want.hash(), overrideIdent{id, &stubArtifact{
 					kind: pkg.KindTar,
-				}}}, wantPathname, want, nil},
+				}}}, wantPathname, want, pkg.WCache, nil},
 
 				{"identical checksum", overrideIdent{id0, &stubArtifact{
 					kind: pkg.KindTar,
 					cure: makeSample,
-				}}, wantPathname0, want, nil},
+				}}, wantPathname0, want, pkg.WNew, nil},
 
 				{"cure fault", overrideIdent{pkg.ID{0xff, 0}, &stubArtifact{
 					kind: pkg.KindTar,
 					cure: func(t *pkg.TContext) error {
 						return makeGarbage(t.GetWorkDir(), stub.UniqueError(0xcafe))
 					},
-				}}, nil, nil, stub.UniqueError(0xcafe)},
+				}}, nil, nil, pkg.WNew, stub.UniqueError(0xcafe)},
 
 				{"checksum mismatch", overrideChecksum{pkg.Checksum{}, overrideIdent{pkg.ID{0xff, 1}, &stubArtifact{
 					kind: pkg.KindTar,
 					cure: func(t *pkg.TContext) error {
 						return makeGarbage(t.GetWorkDir(), nil)
 					},
-				}}}, nil, nil, &pkg.ChecksumMismatchError{
+				}}}, nil, nil, pkg.WNew, &pkg.ChecksumMismatchError{
 					Got: pkg.MustDecode(
 						"CUx-3hSbTWPsbMfDhgalG4Ni_GmR9TnVX8F99tY_P5GtkYvczg9RrF5zO0jX9XYT",
 					),
@@ -1050,7 +1058,7 @@ func TestCache(t *testing.T) {
 					pkg.ID{0xff, 2},
 					new(want.hash()),
 					testdata, nil,
-				), nil, nil, pkg.InvalidFileModeError(
+				), nil, nil, pkg.WCache, pkg.InvalidFileModeError(
 					fs.ModeDir | 0500,
 				)},
 
@@ -1064,7 +1072,7 @@ func TestCache(t *testing.T) {
 						_, err = io.ReadAll(r)
 						return err
 					},
-				}}, nil, nil, &os.PathError{
+				}}, nil, nil, pkg.WNew, &os.PathError{
 					Op: "read",
 					Path: base.Append(
 						"checksum",
@@ -1078,14 +1086,14 @@ func TestCache(t *testing.T) {
 					cure: func(t *pkg.TContext) error {
 						return nil
 					},
-				}}, nil, nil, pkg.NoOutputError{}},
+				}}, nil, nil, pkg.WNew, pkg.NoOutputError{}},
 
 				{"file output", overrideIdent{pkg.ID{0xff, 5}, &stubArtifact{
 					kind: pkg.KindTar,
 					cure: func(t *pkg.TContext) error {
 						return os.WriteFile(t.GetWorkDir().String(), []byte{0}, 0400)
 					},
-				}}, nil, nil, errors.New("non-file artifact produced regular file")},
+				}}, nil, nil, pkg.WNew, errors.New("non-file artifact produced regular file")},
 
 				{"symlink output", overrideIdent{pkg.ID{0xff, 6}, &stubArtifact{
 					kind: pkg.KindTar,
@@ -1095,7 +1103,7 @@ func TestCache(t *testing.T) {
 							t.GetWorkDir().String(),
 						)
 					},
-				}}, nil, nil, pkg.InvalidFileModeError(
+				}}, nil, nil, pkg.WNew, pkg.InvalidFileModeError(
 					fs.ModeSymlink | 0777,
 				)},
 
@@ -1115,8 +1123,8 @@ func TestCache(t *testing.T) {
 					},
 				}, base.Append(
 					"identifier",
-					"xMDWovje7OfyIaDy_2VnjpKxRqSOQ_LoeD946t-3WsS2V2SeMJ7nDGrNfpa4Pbc-",
+					"gIH5eti07nBAhVti3ZTn8EIGOBCZWWvNpxg5CmCZlDzIC4mBdomPmQLeEpf1IQg9",
-				), want, nil},
+				), want, pkg.WNew, nil},
 
 				{"substitutable", &stubArtifactF{
 					kind:   pkg.KindExec,
@@ -1134,14 +1142,14 @@ func TestCache(t *testing.T) {
 					},
 				}, base.Append(
 					"identifier",
-					"k2ilgG5KQ9NXnMoT2oB6NdwOnSPRn_H24oXQc4l6qOYIxIG9XfuEczeyrR8UEv_f",
+					"VGjpp7NVw3OYLpgOQumfM0KcJgY3suz6torykUczcg4bGT24ySkPn5hy-4dNqqkR",
-				), want, nil},
+				), want, pkg.WSubstitute, nil},
 			})
 
-			if c0, err := unsafeOpen(
+			if c0, err := pkg.Open(
 				t.Context(),
 				message.New(nil),
-				0, 0, 0, base, false,
+				base, &skipLock,
 			); err != nil {
 				t.Fatalf("open: error = %v", err)
 			} else {
@@ -1163,8 +1171,8 @@ func TestCache(t *testing.T) {
 						},
 					}, base.Append(
 						"identifier",
-						"_EmV5nsYZ2UWHgRmLDMU8i-rJWDx-kv5_1pFrzQI7vMMCM5mAXivO8UZtVfOqMR_",
+						"zeZ4JEZ0atAKl6Am67cBID6-KR18nZGgeYfU4qTuYaWhQC4eAn0dyTXdIBH9Bos8",
-					), want, nil},
+					), want, pkg.WSubstitute, nil},
 				})
 			}
 
@@ -1188,15 +1196,15 @@ func TestCache(t *testing.T) {
 			"identifier": {Mode: fs.ModeDir | 0700},
 			"identifier/HnySzeLQvSBZuTUcvfmLEX_OmH4yJWWH788NxuLuv7kVn8_uPM6Ks4rqFWM2NZJY": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
 			"identifier/Zx5ZG9BAwegNT3zQwCySuI2ktCXxNgxirkGLFjW4FW06PtojYVaCdtEw8yuntPLa": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
-			"identifier/_EmV5nsYZ2UWHgRmLDMU8i-rJWDx-kv5_1pFrzQI7vMMCM5mAXivO8UZtVfOqMR_": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
+			"identifier/zeZ4JEZ0atAKl6Am67cBID6-KR18nZGgeYfU4qTuYaWhQC4eAn0dyTXdIBH9Bos8": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
 			"identifier/___9_QAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/7lfQ4QwSpV8nw7IDh0JiQ_jqUPrPv3_Vfie034RxsSy-cy4vO8DVvxgpx2LW08oO")},
 			"identifier/_wgAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/7lfQ4QwSpV8nw7IDh0JiQ_jqUPrPv3_Vfie034RxsSy-cy4vO8DVvxgpx2LW08oO")},
 			"identifier/_woAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/7lfQ4QwSpV8nw7IDh0JiQ_jqUPrPv3_Vfie034RxsSy-cy4vO8DVvxgpx2LW08oO")},
-			"identifier/k2ilgG5KQ9NXnMoT2oB6NdwOnSPRn_H24oXQc4l6qOYIxIG9XfuEczeyrR8UEv_f": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
+			"identifier/VGjpp7NVw3OYLpgOQumfM0KcJgY3suz6torykUczcg4bGT24ySkPn5hy-4dNqqkR": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
-			"identifier/xMDWovje7OfyIaDy_2VnjpKxRqSOQ_LoeD946t-3WsS2V2SeMJ7nDGrNfpa4Pbc-": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
+			"identifier/gIH5eti07nBAhVti3ZTn8EIGOBCZWWvNpxg5CmCZlDzIC4mBdomPmQLeEpf1IQg9": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
-			"substitute/OyBGorh72Z9kVw35JUa8FbqDbpR4DqT-MX1jic0uKN5PdYmUBiAF38BRsIRnBigf": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
+			"substitute/nWPg893oqn_YNN8kgfZrs_LVLwP90e0mKxqU8UwoazQh-yBPwhoviD7of6YALx-M": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/qRN6in76LndiiOZJheHkwyW8UT1N5-f-bXvHfDvwrMw2fSkOoZdh8pWE1qhLk65b")},
 
 			"work": {Mode: fs.ModeDir | 0700},
 		}},
@@ -1235,7 +1243,7 @@ func TestCache(t *testing.T) {
 					pkg.ID{0xff, 1},
 					nil,
 					nil, stub.UniqueError(0xbad),
-				), nil, nil, stub.UniqueError(0xbad)},
+				), nil, nil, pkg.WNew, stub.UniqueError(0xbad)},
 
 				{"file output", overrideIdent{pkg.ID{0xff, 2}, &stubArtifact{
 					kind: pkg.KindTar,
@@ -1246,7 +1254,7 @@ func TestCache(t *testing.T) {
 							0400,
 						)
 					},
-				}}, nil, nil, errors.New(
+				}}, nil, nil, pkg.WNew, errors.New(
 					"non-file artifact produced regular file",
 				)},
 			})
@@ -1363,14 +1371,14 @@ func TestCache(t *testing.T) {
 				}}}, base.Append(
 					"identifier",
 					pkg.Encode(pkg.ID{0xff, 0}),
-				), want, nil},
+				), want, pkg.WNew, nil},
 
 				{"reject", overrideChecksum{want.hash(), overrideIdent{pkg.ID{0xfe, 1}, &stubArtifact{
 					kind: pkg.KindTar,
 					cure: func(t *pkg.TContext) error {
 						return makeGarbage(t.GetWorkDir(), stub.UniqueError(0xbad))
 					},
-				}}}, nil, nil, stub.UniqueError(0xbad)},
+				}}}, nil, nil, pkg.WNew, stub.UniqueError(0xbad)},
 
 				{"match", overrideChecksum{want.hash(), overrideIdent{pkg.ID{0xff, 1}, &stubArtifact{
 					kind: pkg.KindTar,
@@ -1380,7 +1388,7 @@ func TestCache(t *testing.T) {
 				}}}, base.Append(
 					"identifier",
 					pkg.Encode(pkg.ID{0xff, 1}),
-				), want, nil},
+				), want, pkg.WNew, nil},
 			})
 		}, expectsFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -1408,7 +1416,7 @@ func TestCache(t *testing.T) {
 				), base.Append(
 					"identifier",
 					pkg.Encode(pkg.Checksum{0xfe, 0}),
-				), expectsChecksum{0xff, 0}, nil},
+				), expectsChecksum{0xff, 0}, pkg.WNew, nil},
 			})
 
 			for _, p := range [][]string{
@@ -1485,7 +1493,7 @@ func TestCache(t *testing.T) {
 				), expectsFS{
 					".":      {Mode: fs.ModeDir | 0500},
 					"result": {Mode: 0444},
-				}, nil},
+				}, pkg.WNew, nil},
 
 				{"substituted", substituted, base.Append(
 					"identifier",
@@ -1493,7 +1501,7 @@ func TestCache(t *testing.T) {
 				), expectsFS{
 					".":      {Mode: fs.ModeDir | 0500},
 					"result": {Mode: 0444},
-				}, nil},
+				}, pkg.WSubstitute, nil},
 			})
 		}, expectsFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -1504,18 +1512,18 @@ func TestCache(t *testing.T) {
 			"checksum/wILUy2izpj2sgKJVhGUGIAde1XVuqvp5BpFMIQHanT5Q8R6jK4QPVSrJsjZh-njV":        {Mode: 0400, Data: []byte("destroyed")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/0Jmc-vGnNDlXTD3jxy-4DGxHW-2-2LtLZ9SXaJtDIqu4uyHfDwDbghNBQ2aYRpab": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
+			"identifier/CLyyxJWn1yUGFs_0KnJ4ZSU2hH4-elvGFRB36x14LrNrKBJPxvORhL9O4Rc7oeYU": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/wILUy2izpj2sgKJVhGUGIAde1XVuqvp5BpFMIQHanT5Q8R6jK4QPVSrJsjZh-njV")},
-			"identifier/L-A8SK4ZX631eyealbJVH08u5pAVEf2NMk8RmLlxl7BVADkU4hNjWD6pi5H7uL1F": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/wILUy2izpj2sgKJVhGUGIAde1XVuqvp5BpFMIQHanT5Q8R6jK4QPVSrJsjZh-njV")},
+			"identifier/arv8a6z4i0x6pUb5Z2T-3iE4ETvyZj-uReHGKsS7uiBgMgKNEOzTGG3LIZb8vp0L": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/wILUy2izpj2sgKJVhGUGIAde1XVuqvp5BpFMIQHanT5Q8R6jK4QPVSrJsjZh-njV")},
-			"identifier/VbVV2dFVosCriHnG9t5vwfW4lbHvzOkV2eYwpGpPJZOgNBc0g1wZAhbdKEweLqmW": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
+			"identifier/heRgWhNJmhm898V68kw0ta76t4rP1o29tYW_TrdyBWXGfo37K3QWA7Z-JkLXAwcn": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
-			"identifier/aSMwvPAwdsIF9e1spuLyRNEc8aTFA4HRVasoNqGjxdm1laSMs2h2teGsoSzLp_pR": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/wILUy2izpj2sgKJVhGUGIAde1XVuqvp5BpFMIQHanT5Q8R6jK4QPVSrJsjZh-njV")},
+			"identifier/q-VoVBI3IjcWTqwIokpi3y05CP113CHgHslc-XWnhOvDULwzVc3q9Y5xOCm_YyLZ": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
 
 			"status": {Mode: fs.ModeDir | 0700},
-			"status/0Jmc-vGnNDlXTD3jxy-4DGxHW-2-2LtLZ9SXaJtDIqu4uyHfDwDbghNBQ2aYRpab": {Mode: fs.ModeSymlink | 0777, Data: []byte("dzO8FEY9lu4hwRT6BfRZOX-uYGsC_5XH4jEJ7sJyThcmG9J_w1ArOAaUCGfL8wAM")},
+			"status/q-VoVBI3IjcWTqwIokpi3y05CP113CHgHslc-XWnhOvDULwzVc3q9Y5xOCm_YyLZ": {Mode: fs.ModeSymlink | 0777, Data: []byte("dP-6_wIDRRouOaOF-nkBy-IaUbLdYHbOUTrptu7j_qfW01mnHSjYJ0oykUmvUd2x")},
-			"status/VbVV2dFVosCriHnG9t5vwfW4lbHvzOkV2eYwpGpPJZOgNBc0g1wZAhbdKEweLqmW": {Mode: 0400, Data: []byte(statusHeader + "destroyed")},
+			"status/heRgWhNJmhm898V68kw0ta76t4rP1o29tYW_TrdyBWXGfo37K3QWA7Z-JkLXAwcn": {Mode: 0400, Data: []byte(statusHeader + "destroyed")},
-			"status/dzO8FEY9lu4hwRT6BfRZOX-uYGsC_5XH4jEJ7sJyThcmG9J_w1ArOAaUCGfL8wAM": {Mode: 0400, Data: []byte(statusHeader + "destroyed")},
+			"status/dP-6_wIDRRouOaOF-nkBy-IaUbLdYHbOUTrptu7j_qfW01mnHSjYJ0oykUmvUd2x": {Mode: 0400, Data: []byte(statusHeader + "destroyed")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
-			"substitute/dzO8FEY9lu4hwRT6BfRZOX-uYGsC_5XH4jEJ7sJyThcmG9J_w1ArOAaUCGfL8wAM": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
+			"substitute/dP-6_wIDRRouOaOF-nkBy-IaUbLdYHbOUTrptu7j_qfW01mnHSjYJ0oykUmvUd2x": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/UjZSrgz7_B7XMd9fHU7jM33UZhWlFgX0rz7JZbCBYR28bCS7jr_CAJdcDhi52ruE")},
 
 			"work": {Mode: fs.ModeDir | 0700},
 		}},
@@ -1586,14 +1594,14 @@ func TestCache(t *testing.T) {
 				{"extern", a, base.Append(
 					"identifier",
 					pkg.Encode(wantIdent.Value()),
-				), wantOutput, nil},
+				), wantOutput, pkg.WExternal, nil},
 
 				{"substitute", _a, base.Append(
 					"identifier",
 					pkg.Encode(_wantIdent.Value()),
-				), _wantOutput, nil},
+				), _wantOutput, pkg.WExternal, nil},
 
-				{"mismatch", kca, nil, nil, &pkg.ChecksumMismatchError{
+				{"mismatch", kca, nil, nil, pkg.WExternal, &pkg.ChecksumMismatchError{
 					Got: wantChecksum,
 				}},
 			})
@@ -1607,17 +1615,163 @@ func TestCache(t *testing.T) {
 			"checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl/result": {Mode: fs.ModeSymlink | 0777, Data: []byte("/proc/nonexistent")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/4HqRo4uTwRQjfy3d2cujMoDC_pC4iv20h4a7NYlx0UdbVuky18o5iK78TFEfPX2U": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/k8yyhlBV3JpYzzywAnrRWkfp2TmgIDNC6FqMFwrrR2x0C3unBLveDNKgigOjG9MM": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
-			"identifier/7AZcJm58ghFyTVf_v2baSntgpsxkP5el7ti9dC77C29n8YTEqQW9jRW92KGNdYnz": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
+			"identifier/Xys8hPpJsKirZmTTuT7SwQ6661TCp_ZRu8iUjPPD7pC5E3ll7xw4zhNlZ2PVcz_-": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
-			"identifier/c4aCI00C-ZVyo_FQDQLl1OYK4U_kjzxwrLdFDiXMHnbMcZXCkXo_nxUWauScZ_4V": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/8sInO_dhPW9kweit7jVuH_vtMkRxlZT7XE4_yEKPZmpGkgVxkmxz0OpXgbMsH6ET": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
-			"identifier/cNoG77frXGRCJa7fUi1INKUEQg7L4qrX5acsSv-wqZdGZT7dQwM93rD3at6kSFFF": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
+			"identifier/ofaXbB5gIza_7W4Rzo5XDe_8FwlCPKWn3TBcmGgFAkkTWMl5GXGmOzX89Jd2Mk2A": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
-			"identifier/gvCqzexZVqXjF8B5lKMcP5onmq3jJ6AKqzOW_WN0Fl2yTr9NKhPt9l_ClD2EOSlS": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
+			"identifier/8VL-egZySw-RbnHZtxGWdf5Z2v9S9CihrdFwa54Bc5EYMQcEgWEem7QrdCTWlCb8": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
 
 			"status": {Mode: fs.ModeDir | 0700},
-			"status/gvCqzexZVqXjF8B5lKMcP5onmq3jJ6AKqzOW_WN0Fl2yTr9NKhPt9l_ClD2EOSlS": {Mode: 0400, Data: []byte("\x00")},
+			"status/8VL-egZySw-RbnHZtxGWdf5Z2v9S9CihrdFwa54Bc5EYMQcEgWEem7QrdCTWlCb8": {Mode: 0400, Data: []byte("\x00")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
-			"substitute/qOYrxy9ztKeOA96Os811_0Ox5sd8FBOxis6psJAnRJL5MLazFMaqmd4g7t7k1OHk": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"substitute/socGRnhdsJlJ4Z01ZwHFZdLzFH0rWvoaJrylcUKtvhBdGsE7VoYl-vdUuvfK8B4I": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+
+			"work": {Mode: fs.ModeDir | 0700},
+		}},
+
+		{"extern shallow", pkg.CExternShallow, nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
+			a := &stubArtifactF{
+				kind:   pkg.KindExec,
+				params: []byte("extern"),
+			}
+			wantIdent := c.Ident(a)
+			wantOutput := expectsFS{
+				".":      {Mode: fs.ModeDir | 0500},
+				"result": {Mode: fs.ModeSymlink | 0777, Data: []byte("/proc/nonexistent")},
+			}
+			var wantChecksum pkg.Checksum
+			if err := pkg.SumFS(
+				&wantChecksum,
+				fstest.MapFS(wantOutput),
+				".",
+			); err != nil {
+				t.Fatal(err)
+			}
+			wantChecksumH := unique.Make(wantChecksum)
+
+			_a := &stubArtifactF{
+				kind:   pkg.KindExec,
+				params: []byte("extern substitute"),
+				deps:   []pkg.Artifact{pkg.NewFile("", nil)},
+			}
+			_wantIdent := c.Ident(_a)
+			_wantOutput := expectsFS{
+				".": {Mode: fs.ModeDir | 0500},
+			}
+			var _wantChecksum pkg.Checksum
+			if err := pkg.SumFS(
+				&_wantChecksum,
+				fstest.MapFS(_wantOutput),
+				".",
+			); err != nil {
+				t.Fatal(err)
+			}
+			_wantChecksumH := unique.Make(_wantChecksum)
+
+			kca := pkg.NewExec(
+				"", "",
+				new(pkg.Checksum), 0, false, false,
+				fhs.AbsRoot, nil, fhs.AbsRoot, nil,
+			)
+			kcIdent := c.Ident(kca)
+
+			fia := &stubArtifactF{
+				kind:   pkg.KindExec,
+				params: []byte("flood input"),
+				deps:   []pkg.Artifact{_a},
+			}
+			fiaIdent := c.Ident(fia)
+
+			flia := &stubArtifactF{
+				kind:   pkg.KindExec,
+				params: []byte("flood input local"),
+				deps:   []pkg.Artifact{_a},
+			}
+			fliaIdent := c.Ident(flia)
+
+			h := &stubArtifactF{
+				kind:   pkg.KindExec,
+				params: []byte("hanging input"),
+			}
+
+			fhia := &stubArtifactF{
+				kind:   pkg.KindExec,
+				params: []byte("flood input local"),
+				deps:   []pkg.Artifact{h},
+			}
+			fhiaIdent := c.Ident(fhia)
+
+			c.SetExternal(stubExtern{
+				artifact: map[unique.Handle[pkg.ID]]pkg.Checksum{
+					wantIdent:  wantChecksum,
+					_wantIdent: _wantChecksum,
+					kcIdent:    wantChecksum,
+					fiaIdent:   wantChecksum,
+					fliaIdent:  wantChecksum,
+					fhiaIdent:  wantChecksum,
+				},
+				checksum: map[unique.Handle[pkg.Checksum]]fstest.MapFS{
+					wantChecksumH:  fstest.MapFS(wantOutput),
+					_wantChecksumH: fstest.MapFS(_wantOutput),
+				},
+				status: map[unique.Handle[pkg.ID]]string{
+					wantIdent: "\x00",
+					kcIdent:   "unreachable",
+				},
+			})
+
+			cureMany(t, c, []cureStep{
+				{"extern", a, base.Append(
+					"identifier",
+					pkg.Encode(wantIdent.Value()),
+				), wantOutput, pkg.WExternal, nil},
+
+				{"flood shallow extern", fia, base.Append(
+					"identifier",
+					pkg.Encode(fiaIdent.Value()),
+				), wantOutput, pkg.WExternal, nil},
+
+				{"substitute", _a, base.Append(
+					"identifier",
+					pkg.Encode(_wantIdent.Value()),
+				), _wantOutput, pkg.WExternal, nil},
+
+				{"flood shallow local", flia, base.Append(
+					"identifier",
+					pkg.Encode(fliaIdent.Value()),
+				), wantOutput, pkg.WExternal, nil},
+
+				{"flood shallow hanging", fhia, nil, nil,
+					pkg.WNew, pkg.HangingInputError(c.Ident(h))},
+
+				{"mismatch", kca, nil, nil, pkg.WExternal, &pkg.ChecksumMismatchError{
+					Got: wantChecksum,
+				}},
+			})
+		}, expectsFS{
+			".": {Mode: fs.ModeDir | 0700},
+
+			"checksum": {Mode: fs.ModeDir | 0700},
+			"checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU":        {Mode: fs.ModeDir | 0500},
+			"checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl":        {Mode: fs.ModeDir | 0500},
+			"checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl/result": {Mode: fs.ModeSymlink | 0777, Data: []byte("/proc/nonexistent")},
+
+			"identifier": {Mode: fs.ModeDir | 0700},
+			"identifier/3fYJjSiWhklt7TK9MPVLGk5_8AIU8ostTcFPXULJf_qeAVG6pmC-Cqqu4ZhEXRxn": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
+			"identifier/8VL-egZySw-RbnHZtxGWdf5Z2v9S9CihrdFwa54Bc5EYMQcEgWEem7QrdCTWlCb8": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
+			"identifier/8sInO_dhPW9kweit7jVuH_vtMkRxlZT7XE4_yEKPZmpGkgVxkmxz0OpXgbMsH6ET": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/Xys8hPpJsKirZmTTuT7SwQ6661TCp_ZRu8iUjPPD7pC5E3ll7xw4zhNlZ2PVcz_-": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
+			"identifier/k8yyhlBV3JpYzzywAnrRWkfp2TmgIDNC6FqMFwrrR2x0C3unBLveDNKgigOjG9MM": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/mXlNz_v77nW7jstn_rJn4RL7dCQlkakM0y-HjO6tkDubtzaj-wCmW1hIr2Gk64_O": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
+
+			"status": {Mode: fs.ModeDir | 0700},
+			"status/8VL-egZySw-RbnHZtxGWdf5Z2v9S9CihrdFwa54Bc5EYMQcEgWEem7QrdCTWlCb8": {Mode: 0400, Data: []byte("\x00")},
+
+			"substitute": {Mode: fs.ModeDir | 0700},
+			"substitute/socGRnhdsJlJ4Z01ZwHFZdLzFH0rWvoaJrylcUKtvhBdGsE7VoYl-vdUuvfK8B4I": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"substitute/MccYezQ4pshkeBV4w_aAEIwvZdKHL3OAgAkR3ouZ43EF94Ur1HBHaN7njPfJAj50": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
+			"substitute/VV5W0_DiA1iylaqbKFThp1ZpV_y1ccVS1XyqDnDaXoHQ-EEyPI4XFrQHcHOF2hWG": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fHkl_RuHOoc4rso__nV-qreikovd6Yhrq5mpBlkf5hmPGaxDlik2bYOQ4dhUQjtl")},
 
 			"work": {Mode: fs.ModeDir | 0700},
 		}},
@@ -1635,7 +1789,7 @@ func TestErrors(t *testing.T) {
 	}{
 		{"InvalidLookupError", pkg.InvalidLookupError{
 			0xff, 0xf0,
-		}, "attempting to look up non-dependency artifact __AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"},
+		}, "attempting to look up non-input artifact __AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"},
 
 		{"InvalidArtifactError", pkg.InvalidArtifactError{
 			0xff, 0xfd,
@@ -1883,7 +2037,7 @@ func (earlyFailureF) Kind() pkg.Kind       { return pkg.KindExec }
 func (earlyFailureF) Params(*pkg.IContext) {}
 func (earlyFailureF) IsExclusive() bool    { return false }
 
-func (a earlyFailureF) Dependencies() []pkg.Artifact {
+func (a earlyFailureF) Inputs() []pkg.Artifact {
 	deps := make([]pkg.Artifact, a)
 	for i := range deps {
 		deps[i] = a - 1
@@ -1901,7 +2055,7 @@ func (a earlyFailureF) Cure(*pkg.FContext) error {
 func BenchmarkEarlyDCE(b *testing.B) {
 	msg := message.New(log.New(os.Stderr, "dce: ", 0))
 	msg.SwapVerbose(testing.Verbose())
-	c, err := pkg.Open(b.Context(), msg, 0, 0, 0, check.MustAbs(b.TempDir()))
+	c, err := pkg.Open(b.Context(), msg, check.MustAbs(b.TempDir()), nil)
 	if err != nil {
 		b.Fatal(err)
 	}
@@ -1950,7 +2104,8 @@ func TestOpen(t *testing.T) {
 		if _, err := pkg.Open(
 			t.Context(),
 			message.New(nil),
-			0, 0, 0, check.MustAbs(container.Nonexistent),
+			check.MustAbs(container.Nonexistent),
+			nil,
 		); !reflect.DeepEqual(err, wantErr) {
 			t.Errorf("Open: error = %#v, want %#v", err, wantErr)
 		}
@@ -1978,7 +2133,8 @@ func TestOpen(t *testing.T) {
 		if _, err := pkg.Open(
 			t.Context(),
 			message.New(nil),
-			0, 0, 0, tempDir.Append("cache"),
+			tempDir.Append("cache"),
+			nil,
 		); !reflect.DeepEqual(err, wantErr) {
 			t.Errorf("Open: error = %#v, want %#v", err, wantErr)
 		}
@@ -2000,7 +2156,8 @@ func TestOpen(t *testing.T) {
 		if _, err := pkg.Open(
 			t.Context(),
 			message.New(nil),
-			0, 0, 0, tempDir.Append("cache"),
+			tempDir.Append("cache"),
+			nil,
 		); !reflect.DeepEqual(err, wantErr) {
 			t.Errorf("Open: error = %#v, want %#v", err, wantErr)
 		}
@@ -2021,7 +2178,7 @@ func TestOpen(t *testing.T) {
 		if _, err := pkg.Open(
 			t.Context(),
 			message.New(nil),
-			0, 0, 0, tempDir.Append("cache"),
+			tempDir.Append("cache"), nil,
 		); !reflect.DeepEqual(err, wantErr) {
 			t.Errorf("Open: error = %#v, want %#v", err, wantErr)
 		}
@@ -2074,8 +2231,8 @@ func TestExtensionRegister(t *testing.T) {
 		if _, err := pkg.Open(
 			t.Context(),
 			message.New(log.Default()),
-			0, 0, 0,
 			check.MustAbs(container.Nonexistent),
+			nil,
 		); !errors.Is(err, os.ErrNotExist) {
 			t.Fatalf("Open: error = %v", err)
 		}
@@ -2113,7 +2270,7 @@ func TestExtensionRegister(t *testing.T) {
 		pkg.Register(pkg.KindCustomOffset, nil)
 
 		t.Cleanup(func() { opened = false })
-		_, _ = pkg.Open(nil, nil, 0, 0, 0, nil)
+		_, _ = pkg.Open(nil, nil, nil, nil)
 		panic("unreachable")
 	})
 
@@ -2124,11 +2281,7 @@ func TestExtensionRegister(t *testing.T) {
 
 		base := check.MustAbs(t.TempDir())
 		t.Cleanup(func() { opened = false })
-		if c, err := pkg.Open(
+		if c, err := pkg.Open(t.Context(), nil, base, nil); err != nil {
-			t.Context(), nil,
-			0, 0, 0,
-			base,
-		); err != nil {
 			t.Fatal(err)
 		} else {
 			c.Close()
@@ -2156,8 +2309,7 @@ func TestExtensionRegister(t *testing.T) {
 		}
 		if _, err := pkg.Open(
 			t.Context(), nil,
-			0, 0, 0,
+			base, nil,
-			base,
 		); !reflect.DeepEqual(err, wantErr) {
 			t.Fatalf("Open: error = %v, want %v", err, wantErr)
 		}
@@ -2178,8 +2330,8 @@ func TestExtensionRegister(t *testing.T) {
 
 		if _, err := pkg.Open(
 			t.Context(), nil,
-			0, 0, 0,
 			base,
+			nil,
 		); !reflect.DeepEqual(err, pkg.ErrWouldPromote) {
 			t.Fatalf("Open: error = %v", err)
 		}
@@ -2192,8 +2344,7 @@ func TestExtensionRegister(t *testing.T) {
 
 		if c, err := pkg.Open(
 			t.Context(), nil,
-			pkg.CPromoteVariant, 0, 0,
+			base, &pkg.CacheAttr{Flags: pkg.CPromoteVariant},
-			base,
 		); err != nil {
 			t.Fatalf("Open: error = %v", err)
 		} else {
@@ -2218,8 +2369,7 @@ func TestExtensionRegister(t *testing.T) {
 
 		if _, err := pkg.Open(
 			t.Context(), nil,
-			0, 0, 0,
+			base, nil,
-			base,
 		); !reflect.DeepEqual(err, pkg.ErrInvalidExtension) {
 			t.Fatalf("Open: error = %v", err)
 		}
@@ -2236,8 +2386,7 @@ func TestExtensionRegister(t *testing.T) {
 
 		if _, err := pkg.Open(
 			t.Context(), nil,
-			0, 0, 0,
+			base, nil,
-			base,
 		); !reflect.DeepEqual(err, pkg.UnsupportedVariantError("rosa")) {
 			t.Fatalf("Open: error = %v", err)
 		}

internal/pkg/tar.go

@@ -16,6 +16,8 @@ type tarArtifact struct {
 	f Artifact
 }
 
+var _ CuresExempt = new(tarArtifact)
+
 // tarArtifactNamed embeds tarArtifact for a [fmt.Stringer] tarball.
 type tarArtifactNamed struct {
 	tarArtifact
@@ -56,8 +58,8 @@ func init() {
 	})
 }
 
-// Dependencies returns a slice containing the backing file.
+// Inputs returns a slice containing the backing file.
-func (a *tarArtifact) Dependencies() []Artifact {
+func (a *tarArtifact) Inputs() []Artifact {
 	return []Artifact{a.f}
 }
 
@@ -170,6 +172,13 @@ func (a *tarArtifact) Cure(t *TContext) (err error) {
 			}
 			break
 
+		case tar.TypeChar:
+			t.GetMessage().Verbosef(
+				"skipping character device %d, %d %q",
+				header.Devmajor, header.Devminor, header.Name,
+			)
+			continue
+
 		case tar.TypeXGlobalHeader:
 			continue // ignore
 
@@ -211,3 +220,7 @@ func (a *tarArtifact) Cure(t *TContext) (err error) {
 	}
 	return
 }
+
+// CuresExempt exempts the cheap [KindTar] implementation often at the end of a
+// [FileArtifact] pipeline.
+func (*tarArtifact) CuresExempt() {}

internal/pkg/tar_test.go

@@ -80,8 +80,8 @@ func TestTar(t *testing.T) {
 			"checksum/" + wantEncode + "/work": {Mode: fs.ModeDir | 0500},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/T68YqeEW5moiwVe4J0wPvjERgyMUd4k_cKKxTcQx6AXqZaQAuuryu-Iv-qxDV6-T": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantEncode)},
+			"identifier/7OZ5ErCxUJyRnaaFvUKhTryjsJAoOBUR2MZpUB1DD57jRa09Xxsh9BUs0dM9z5uH": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantEncode)},
-			"identifier/WbWIIUGl6bqDBsjU-UB69JqOWLjG5waiUJBUBGeeRp3V7FBbwaBe3sG1qm7DlPSk": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantEncode)},
+			"identifier/paWdPW_BowV3345c4GP4xxSNgxVs_7F09m9m7OaH5XbyuI3dTGZ-kFPOXFbwgr5O": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantEncode)},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 
@@ -104,8 +104,8 @@ func TestTar(t *testing.T) {
 			"checksum/" + wantExpandEncode + "/libedac.so": {Mode: fs.ModeSymlink | 0777, Data: []byte("/proc/nonexistent/libedac.so")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/WbWIIUGl6bqDBsjU-UB69JqOWLjG5waiUJBUBGeeRp3V7FBbwaBe3sG1qm7DlPSk": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantExpandEncode)},
+			"identifier/1g2Tcg7pOJkZFxlKploBm4U0vIyMYbxDkcwwydwsF9BMs-w-knFJS41jnqOt16jT": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantExpandEncode)},
-			"identifier/e3BECw_x_vDyTvj2P48MJVgwpgALeXQ90Ye2Y8gr6SwIPtMup6SR2LVcCTDRGpVi": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantExpandEncode)},
+			"identifier/7OZ5ErCxUJyRnaaFvUKhTryjsJAoOBUR2MZpUB1DD57jRa09Xxsh9BUs0dM9z5uH": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantExpandEncode)},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 
@@ -212,24 +212,24 @@ func checkTarHTTP(
 			&client,
 			"file:///testdata",
 			testdataChecksum,
-		), pkg.Gzip)), ignorePathname, want, nil},
+		), pkg.Gzip)), ignorePathname, want, pkg.WNew, nil},
 
 		{"directory", pkg.NewTar(pkg.NewDecompress(
 			&tarDir,
 			pkg.Gzip,
-		)), ignorePathname, want, nil},
+		)), ignorePathname, want, pkg.WNew, nil},
 
 		{"multiple entries", pkg.NewTar(pkg.NewDecompress(
 			&tarDirMulti,
 			pkg.Gzip,
-		)), nil, nil, errors.New(
+		)), nil, nil, pkg.WNew, errors.New(
 			"input directory does not contain a single regular file",
 		)},
 
 		{"bad type", pkg.NewTar(pkg.NewDecompress(
 			&tarDirType,
 			pkg.Gzip,
-		)), nil, nil, errors.New(
+		)), nil, nil, pkg.WNew, errors.New(
 			"input directory does not contain a single regular file",
 		)},
 
@@ -239,6 +239,6 @@ func checkTarHTTP(
 			cure: func(t *pkg.TContext) error {
 				return stub.UniqueError(0xcafe)
 			},
-		}), nil, nil, stub.UniqueError(0xcafe)},
+		}), nil, nil, pkg.WNew, stub.UniqueError(0xcafe)},
 	})
 }

internal/rosa/builtins.go

@@ -18,6 +18,11 @@ const (
 	jobsLE = `"$(expr ` + jobsE + ` '*' 2)"`
 	// jobsLFlagE is expression for flag with double of preferred job count.
 	jobsLFlagE = `"-j$(expr ` + jobsE + ` '*' 2)"`
+
+	// loadE is expression for preferred loadavg target set by [pkg].
+	loadE = `"$` + pkg.EnvLoad + `"`
+	// loadFlagE is expression for flag with preferred loadavg target.
+	loadFlagE = `"-l$` + pkg.EnvLoad + `"`
 )
 
 // newTar wraps [pkg.NewHTTPGetTar] with a simpler function signature.
@@ -102,7 +107,7 @@ func skipGNUTests(tests ...int64) string {
 			buf.WriteString(strconv.Itoa(int(n - 1)))
 			buf.WriteString(" ")
 		}
-		if i == len(tests)-1 || tests[i+1] != n+1 {
+		if i == len(tests)-1 || (tests[i+1] != n+1 && tests[i+1] != n+2) {
 			buf.WriteString(strconv.Itoa(int(n + 1)))
 			buf.WriteString("-")
 		}

internal/rosa/builtins_test.go

@@ -16,6 +16,7 @@ func TestSkipGNUTests(t *testing.T) {
 	}{
 		{[]int64{764}, "1-763 765-"},
 		{[]int64{764, 0xcafe, 37, 9}, "1-8 10-36 38-763 765-51965 51967-"},
+		{[]int64{168, 170, 623, 764}, "1-167 169 171-622 624-763 765-"},
 		{[]int64{1, 2, 0xbed}, "3-3052 3054-"},
 		{[]int64{3, 4}, "1-2 5-"},
 	}

internal/rosa/busybox.go

@@ -1,124 +0,0 @@
-package rosa
-
-import (
-	"fmt"
-	"io"
-	"net/http"
-	"os"
-	"time"
-
-	"hakurei.app/fhs"
-	"hakurei.app/internal/pkg"
-)
-
-// busyboxBin is a busybox binary distribution installed under bin/busybox.
-type busyboxBin struct {
-	// Underlying busybox binary.
-	bin pkg.FileArtifact
-}
-
-// Kind returns the hardcoded [pkg.Kind] value.
-func (a busyboxBin) Kind() pkg.Kind { return kindBusyboxBin }
-
-// Params is a noop.
-func (a busyboxBin) Params(*pkg.IContext) {}
-
-// IsExclusive returns false: Cure performs a trivial filesystem write.
-func (busyboxBin) IsExclusive() bool { return false }
-
-// Dependencies returns the underlying busybox [pkg.FileArtifact].
-func (a busyboxBin) Dependencies() []pkg.Artifact {
-	return []pkg.Artifact{a.bin}
-}
-
-func init() {
-	pkg.Register(kindBusyboxBin, func(r *pkg.IRReader) pkg.Artifact {
-		a := busyboxBin{r.Next().(pkg.FileArtifact)}
-		if _, ok := r.Finalise(); ok {
-			panic(pkg.ErrUnexpectedChecksum)
-		}
-		return a
-	})
-}
-
-// String returns the reporting name of the underlying file prefixed with expand.
-func (a busyboxBin) String() string {
-	return "expand-" + a.bin.(fmt.Stringer).String()
-}
-
-// Cure installs the underlying busybox [pkg.File] to bin/busybox.
-func (a busyboxBin) Cure(t *pkg.TContext) (err error) {
-	var r io.ReadCloser
-	if r, err = t.Open(a.bin); err != nil {
-		return
-	}
-	defer func() {
-		closeErr := r.Close()
-		if err == nil {
-			err = closeErr
-		}
-	}()
-
-	binDir := t.GetWorkDir().Append("bin")
-	if err = os.MkdirAll(binDir.String(), 0700); err != nil {
-		return
-	}
-
-	var w *os.File
-	if w, err = os.OpenFile(
-		binDir.Append("busybox").String(),
-		os.O_WRONLY|os.O_CREATE|os.O_EXCL,
-		0500,
-	); err != nil {
-		return
-	}
-	defer func() {
-		closeErr := w.Close()
-		if err == nil {
-			err = closeErr
-		}
-	}()
-
-	_, err = io.Copy(w, r)
-	return
-}
-
-// newBusyboxBin returns a [pkg.Artifact] containing a busybox installation from
-// the https://busybox.net/downloads/binaries/ binary release.
-func (s *S) newBusyboxBin() pkg.Artifact {
-	var version, url, checksum string
-	switch s.arch {
-	case "amd64":
-		version = "1.35.0"
-		url = "https://busybox.net/downloads/binaries/" +
-			version + "-" + s.linuxArch() + "-linux-musl/busybox"
-		checksum = "L7OBIsPu9enNHn7FqpBT1kOg_mCLNmetSeNMA3i4Y60Z5jTgnlX3qX3zcQtLx5AB"
-	case "arm64":
-		version = "1.31.0"
-		url = "https://busybox.net/downloads/binaries/" +
-			version + "-defconfig-multiarch-musl/busybox-armv8l"
-		checksum = "npJjBO7iwhjW6Kx2aXeSxf8kXhVgTCDChOZTTsI8ZfFfa3tbsklxRiidZQdrVERg"
-
-	default:
-		panic("unsupported target " + s.arch)
-	}
-
-	return pkg.NewExec(
-		"busybox-bin-"+version, s.arch, nil, pkg.ExecTimeoutMax, false, false,
-		fhs.AbsRoot, []string{
-			"PATH=/system/bin",
-		},
-		AbsSystem.Append("bin", "busybox"),
-		[]string{"hush", "-c", "" +
-			"busybox mkdir -p /work/system/bin/ && " +
-			"busybox cp /system/bin/busybox /work/system/bin/ && " +
-			"busybox --install -s /work/system/bin/"},
-		pkg.Path(AbsSystem, true, busyboxBin{pkg.NewHTTPGet(
-			&http.Client{Transport: &http.Transport{
-				// busybox website is really slow to respond
-				TLSHandshakeTimeout: 2 * time.Minute,
-			}}, url,
-			mustDecode(checksum),
-		)}),
-	)
-}

internal/rosa/cmake.go

@@ -61,10 +61,10 @@ func (attr *CMakeHelper) script(t Toolchain, name string) string {
 	}
 
 	generate := "Ninja"
-	test := "ninja " + jobsFlagE + " test"
+	test := "ninja " + jobsFlagE + " " + loadFlagE + " test"
 	if attr.Make {
 		generate = "'Unix Makefiles'"
-		test = "make " + jobsFlagE + " test"
+		test = "make " + jobsFlagE + " " + loadFlagE + " test"
 	}
 	if attr.Test != "" {
 		test = attr.Test
@@ -84,6 +84,7 @@ func (attr *CMakeHelper) script(t Toolchain, name string) string {
 
 	return `
 cmake -G ` + generate + ` \
+	-Wno-author -Wno-unused-cli \
 	-DCMAKE_C_COMPILER_TARGET="${ROSA_TRIPLE}" \
 	-DCMAKE_CXX_COMPILER_TARGET="${ROSA_TRIPLE}" \
 	-DCMAKE_ASM_COMPILER_TARGET="${ROSA_TRIPLE}" \
@@ -97,7 +98,7 @@ cmake -G ` + generate + ` \
 	}), " \\\n\t") + ` \
 	-DCMAKE_INSTALL_PREFIX=/system \
 	'/usr/src/` + name + `/` + filepath.Join(attr.Append...) + `'
-cmake --build . --parallel=` + jobsE + `
+cmake --build . --parallel=` + jobsE + ` -- ` + loadFlagE + `
 DESTDIR=/work cmake --install .
 ` + script
 }

internal/rosa/etc.go

@@ -118,8 +118,8 @@ func init() {
 // IsExclusive returns false: Cure performs a few trivial filesystem writes.
 func (cureEtc) IsExclusive() bool { return false }
 
-// Dependencies returns a slice containing the backing iana-etc release.
+// Inputs returns a slice containing the backing iana-etc release.
-func (a cureEtc) Dependencies() []pkg.Artifact {
+func (a cureEtc) Inputs() []pkg.Artifact {
 	if !a.minimal {
 		return []pkg.Artifact{ianaEtc}
 	}

internal/rosa/gentoo.go

@@ -0,0 +1,104 @@
+package rosa
+
+import (
+	"errors"
+	"io/fs"
+	"os"
+	"path/filepath"
+
+	"hakurei.app/internal/pkg"
+)
+
+// gentooOverlay are symlinks on top of a Gentoo LLVM stage3 tarball for
+// compatibility with the Rosa OS stage0 distribution.
+type gentooOverlay struct{ stage3 pkg.Artifact }
+
+// Kind returns the hardcoded [pkg.Kind] value.
+func (a gentooOverlay) Kind() pkg.Kind { return kindGentooOverlay }
+
+// Params is a noop.
+func (a gentooOverlay) Params(*pkg.IContext) {}
+
+// IsExclusive returns false: Cure performs a trivial filesystem write.
+func (gentooOverlay) IsExclusive() bool { return false }
+
+// Inputs returns the underlying Gentoo stage3.
+func (a gentooOverlay) Inputs() []pkg.Artifact {
+	return []pkg.Artifact{a.stage3}
+}
+
+func init() {
+	pkg.Register(kindGentooOverlay, func(r *pkg.IRReader) pkg.Artifact {
+		a := gentooOverlay{r.Next()}
+		if _, ok := r.Finalise(); ok {
+			panic(pkg.ErrUnexpectedChecksum)
+		}
+		return a
+	})
+}
+
+// String returns a hardcoded name.
+func (a gentooOverlay) String() string { return "gentoo-overlay" }
+
+// Revision returns a hardcoded value incremented on layout changes.
+func (a gentooOverlay) Revision() uint64 { return 0 }
+
+// Cure installs the overlay.
+func (a gentooOverlay) Cure(f *pkg.FContext) (err error) {
+	pathname, _ := f.GetArtifact(a.stage3)
+	var stage3 *os.Root
+	if stage3, err = os.OpenRoot(pathname.String()); err != nil {
+		return err
+	}
+	defer func() {
+		closeErr := stage3.Close()
+		if err == nil {
+			err = closeErr
+		}
+	}()
+	fsys := stage3.FS()
+
+	system := f.GetWorkDir().Append("system")
+	bin := system.Append("bin")
+	if err = os.MkdirAll(bin.String(), 0700); err != nil {
+		return
+	}
+
+	linknames := []string{
+		"../../bin/sh",
+	}
+
+	var dents []os.DirEntry
+
+	const llvm = "usr/lib/llvm"
+	dents, err = fs.ReadDir(fsys, llvm)
+	if err != nil {
+		return
+	}
+	if len(dents) != 1 {
+		return errors.New("stage3 /" + llvm + " contains more than one entry")
+	}
+
+	llvmBin := filepath.Join(llvm, dents[0].Name(), "bin")
+	dents, err = fs.ReadDir(fsys, llvmBin)
+	if err != nil {
+		return
+	}
+	for _, dent := range dents {
+		linknames = append(linknames, filepath.Join(
+			"../..",
+			llvmBin,
+			dent.Name(),
+		))
+	}
+
+	for _, linkname := range linknames {
+		if err = os.Symlink(
+			linkname,
+			bin.Append(filepath.Base(linkname)).String(),
+		); err != nil {
+			return
+		}
+	}
+	return
+}

internal/rosa/go.go

@@ -56,16 +56,15 @@ ln -s \
 
 func init() {
 	const (
-		version  = "1.26.4"
+		version  = "1.25.12"
-		checksum = "fpqJlxa41wKRtbnviYNLk9VxgcL-5oIEDxsriF8svU6kNwQW70oRRA9gTz_ImVoB"
+		checksum = "XNrGD_boJl2-El_a_T3BuTcMin_WPoU-FGddcNG8dcXA8n2QuxZB7kaUaCWu60QX"
 	)
 	meta := Metadata{
-		Name:        "go",
+		Name:        "go-bootstrap",
-		Description: "the Go programming language toolchain",
+		Description: "the Go programming language toolchain (bootstrap)",
 		Website:     "https://go.dev",
 		Version:     version,
-
+		Exclude:     true,
-		ID: 1227,
 	}
 	native.MustRegister(meta.Name, func(t Toolchain) (*Metadata, pkg.Artifact) {
 		var (
@@ -152,8 +151,8 @@ sed -i \
 		)
 
 		go125 := t.newGo(
-			"1.25.11",
+			version,
-			"cnqAQ8wpVZXcM6nHAfSqFkIW4L3H73ALB9rBfKUBbfgg4_pOF3I9zOZARgYQ6MR2",
+			checksum,
 			[]string{"CGO_ENABLED=0"}, `
 sed -i \
 	's,/lib/ld-musl-`+t.linuxArch()+`.so.1,/system/bin/linker,' \
@@ -165,23 +164,6 @@ rm \
 `, go123,
 		)
 
-		return &meta, t.newGo(
+		return &meta, go125
-			version,
-			checksum,
-			finalEnv, `
-sed -i \
-	's,/lib/ld-musl-`+t.linuxArch()+`.so.1,/system/bin/linker,' \
-	cmd/link/internal/`+t.arch+`/obj.go
-sed -i \
-	's/cpu.X86.HasAVX512VBMI/& \&\& cpu.X86.HasPOPCNT/' \
-	internal/runtime/gc/scan/scan_amd64.go
-
-rm \
-	os/root_unix_test.go \
-	cmd/cgo/internal/testsanitizers/tsan_test.go \
-	cmd/cgo/internal/testsanitizers/cshared_test.go
-`, go125,
-		)
-
 	})
 }

internal/rosa/llvm.go

@@ -1,11 +1,9 @@
 package rosa
 
 import (
-	"io/fs"
 	"regexp"
 	"slices"
 	"strings"
-	"unsafe"
 
 	"hakurei.app/internal/pkg"
 )
@@ -13,12 +11,12 @@ import (
 var (
 	_llvmSource    = H("llvm-project")
 	_muslHeaders   = H("musl-headers")
-	_earlyCompilerRT = H("early-compiler-rt")
 	_earlyRuntimes = H("early-runtimes")
 	_musl          = H("musl")
 
 	_bash        = H("bash")
-	_gawk      = H("gawk")
+	_awk         = H("awk")
+	_pythonEarly = H("python-early")
 	_coreutils   = H("coreutils")
 	_diffutils   = H("diffutils")
 	_findutils   = H("findutils")
@@ -50,165 +48,6 @@ func litArgs(verbose bool, skipChecks ...string) string {
 }
 
 func init() {
-	var llvmPatches []KV
-	for _, name := range [...]string{
-		"increase-stack-size-unconditional",
-		"add-rosa-vendor",
-		"xfail-broken-tests",
-		"path-system-include",
-		"path-system-libraries",
-	} {
-		p, err := fs.ReadFile(nativeB, "package/llvm/"+name+".patch")
-		if err != nil {
-			panic(err)
-		}
-		llvmPatches = append(llvmPatches, KV{
-			name,
-			unsafe.String(unsafe.SliceData(p), len(p)),
-		})
-	}
-
-	native.MustRegister("early-compiler-rt", func(t Toolchain) (*Metadata, pkg.Artifact) {
-		meta := Metadata{
-			Name:        "early-compiler-rt",
-			Description: "early LLVM runtime: compiler-rt",
-
-			Dependencies: P{_musl},
-		}
-		_meta, source := t.MustLoad(_llvmSource)
-		meta.Version = _meta.Version
-		major, _, _ := strings.Cut(meta.Version, ".")
-		return &meta, t.NewPackage("early-compiler-rt", meta.Version, source, &PackageAttr{
-			Flag: TExclusive,
-		}, &CMakeHelper{
-			Append: []string{"compiler-rt"},
-
-			Cache: []KV{
-				{"ENABLE_LINKER_BUILD_ID", "ON"},
-
-				// libc++ not yet available
-				{"CMAKE_CXX_COMPILER_TARGET", ""},
-
-				{"LLVM_HOST_TRIPLE", `"${ROSA_TRIPLE}"`},
-				{"LLVM_DEFAULT_TARGET_TRIPLE", `"${ROSA_TRIPLE}"`},
-				{"LLVM_ENABLE_RTTI", "ON"},
-				{"LLVM_BUILD_LLVM_DYLIB", "ON"},
-				{"LLVM_LINK_LLVM_DYLIB", "ON"},
-				{"LLVM_ENABLE_PER_TARGET_RUNTIME_DIR", "ON"},
-
-				{"COMPILER_RT_BUILD_BUILTINS", "ON"},
-				{"COMPILER_RT_DEFAULT_TARGET_ONLY", "ON"},
-				{"COMPILER_RT_USE_BUILTINS_LIBRARY", "ON"},
-				{"COMPILER_RT_SANITIZERS_TO_BUILD", "asan"},
-				{"COMPILER_RT_BUILD_GWP_ASAN", "OFF"},
-
-				// does not work without libunwind
-				{"COMPILER_RT_BUILD_CTX_PROFILE", "OFF"},
-				{"COMPILER_RT_BUILD_LIBFUZZER", "OFF"},
-				{"COMPILER_RT_BUILD_MEMPROF", "OFF"},
-				{"COMPILER_RT_BUILD_PROFILE", "OFF"},
-				{"COMPILER_RT_BUILD_XRAY", "OFF"},
-			},
-			SkipTest: true,
-			Script: `
-mkdir -p "/work/system/lib/clang/` + major + `/lib/"
-ln -s \
-	"../../../${ROSA_TRIPLE}" \
-	"/work/system/lib/clang/` + major + `/lib/"
-
-ln -s \
-	"clang_rt.crtbegin-` + t.linuxArch() + `.o" \
-	"/work/system/lib/${ROSA_TRIPLE}/crtbeginS.o"
-ln -s \
-	"clang_rt.crtend-` + t.linuxArch() + `.o" \
-	"/work/system/lib/${ROSA_TRIPLE}/crtendS.o"
-`,
-		},
-			_python,
-
-			_muslHeaders,
-			_kernelHeaders,
-		)
-	})
-
-	native.MustRegister("early-runtimes", func(t Toolchain) (*Metadata, pkg.Artifact) {
-		meta := Metadata{
-			Name:        "early-runtimes",
-			Description: "early LLVM runtimes: libunwind, libcxx, libcxxabi",
-
-			Dependencies: P{
-				_earlyCompilerRT,
-			},
-		}
-		_meta, source := t.MustLoad(_llvmSource)
-		meta.Version = _meta.Version
-
-		return &meta, t.NewPackage("early-runtimes", meta.Version, source, &PackageAttr{
-			Flag: TExclusive,
-		}, &CMakeHelper{
-			Append: []string{"runtimes"},
-
-			Cache: []KV{
-				{"ENABLE_LINKER_BUILD_ID", "ON"},
-
-				// libc++ not yet available
-				{"CMAKE_CXX_COMPILER_WORKS", "ON"},
-
-				{"LLVM_HOST_TRIPLE", `"${ROSA_TRIPLE}"`},
-				{"LLVM_DEFAULT_TARGET_TRIPLE", `"${ROSA_TRIPLE}"`},
-				{"LLVM_ENABLE_RTTI", "ON"},
-				{"LLVM_BUILD_LLVM_DYLIB", "ON"},
-				{"LLVM_LINK_LLVM_DYLIB", "ON"},
-				{"LLVM_ENABLE_RUNTIMES", "'libunwind;libcxx;libcxxabi'"},
-
-				{"LIBUNWIND_ENABLE_ASSERTIONS", "OFF"},
-				{"LIBUNWIND_USE_COMPILER_RT", "ON"},
-				{"LIBCXX_HAS_MUSL_LIBC", "ON"},
-				{"LIBCXX_USE_COMPILER_RT", "ON"},
-				{"LIBCXX_CXX_ABI", "libcxxabi"},
-				{"LIBCXX_ENABLE_STATIC_ABI_LIBRARY", "OFF"},
-				{"LIBCXX_HARDENING_MODE", "fast"},
-				{"LIBCXX_HAS_ATOMIC_LIB", "OFF"},
-				{"LIBCXXABI_USE_COMPILER_RT", "ON"},
-				{"LIBCXXABI_USE_LLVM_UNWINDER", "ON"},
-				{"LIBCXXABI_ENABLE_STATIC_UNWINDER", "OFF"},
-				{"LIBCXXABI_HAS_CXA_THREAD_ATEXIT_IMPL", "OFF"},
-
-				{"LLVM_ENABLE_ZLIB", "FORCE_ON"},
-				{"LLVM_ENABLE_ZSTD", "FORCE_ON"},
-				{"LLVM_ENABLE_LIBXML2", "OFF"},
-			},
-			SkipTest: true,
-		},
-			_python,
-
-			_zlib,
-			_zstd,
-			_earlyCompilerRT,
-			_kernelHeaders,
-		)
-	})
-
-	const (
-		version  = "22.1.7"
-		checksum = "GFjsoTzJ72YWQuAaNmlO67IIkoZ8Z12u3n0dOEMSpltmyXUJp8e3cccWDrscXILZ"
-	)
-
-	native.MustRegister("llvm-project", func(t Toolchain) (*Metadata, pkg.Artifact) {
-		meta := Metadata{
-			Name:        "llvm-project",
-			Description: "LLVM monorepo with Rosa OS patches",
-			Version:     version,
-
-			ID: 1830,
-		}
-		return &meta, t.NewPatchedSource("llvm-"+version, newFromGitHub(
-			"llvm/llvm-project",
-			"llvmorg-"+version,
-			checksum,
-		), true, llvmPatches...)
-	})
-
 	native.MustRegister("llvm", func(t Toolchain) (*Metadata, pkg.Artifact) {
 		meta := Metadata{
 			Name:        "llvm",
@@ -341,6 +180,13 @@ ln -s \
 
 		return &meta, t.NewPackage("llvm", meta.Version, source, &PackageAttr{
 			Flag: TExclusive,
+			Bin: []string{
+				"chmod",
+				"mkdir",
+				"rm",
+				"tr",
+				"awk",
+			},
 		}, &CMakeHelper{
 			Append: []string{"llvm"},
 
@@ -358,22 +204,13 @@ ln -s clang++ /work/system/bin/c++
 			// on 3-stage determinism to test later stages.
 			SkipTest: t.stage.isStage0(),
 
-			Test: `
+			Test: "ninja " + jobsFlagE + " " + loadFlagE + " check-all",
-chmod +w /bin && ln -s \
-	../system/bin/chmod \
-	../system/bin/mkdir \
-	../system/bin/rm \
-	../system/bin/tr \
-	../system/bin/awk \
-	/bin
-ninja ` + jobsFlagE + ` check-all
-`,
 		},
-			_python,
+			_pythonEarly,
 			_perl,
 			_diffutils,
 			_bash,
-			_gawk,
+			_awk,
 			_coreutils,
 			_findutils,
 

internal/rosa/llvm_test.go

@@ -8,7 +8,7 @@ import (
 )
 
 func TestLLVMInputs(t *testing.T) {
-	const wantInputCount = 553
+	const wantInputCount = 470
 
 	_, llvm := rosa.Native().Std().MustLoad(rosa.H("llvm"))
 	var n int

internal/rosa/make.go

@@ -56,7 +56,7 @@ func (attr *MakeHelper) extra(flag int) P {
 	extra := P{_make}
 	if (attr == nil || !attr.OmitDefaults) && flag&TEarly == 0 {
 		extra = append(extra,
-			_gawk,
+			_awk,
 			_coreutils,
 		)
 	}
@@ -89,7 +89,7 @@ func (attr *MakeHelper) wantsDir() (string, bool) {
 	if attr != nil && attr.InPlace {
 		return helperInPlace, false
 	}
-	return `"$(mktemp -d)"`, false
+	return "/cure/", true
 }
 
 // script generates the cure script.
@@ -160,7 +160,8 @@ func (attr *MakeHelper) script(t Toolchain, name string) string {
 
 	scriptMake := `
 make \
-	` + jobsFlagE
+	` + jobsFlagE + ` \
+	` + loadFlagE
 	if len(attr.Make) > 0 {
 		scriptMake += " \\\n\t" + strings.Join(attr.Make, " \\\n\t")
 	}
@@ -170,6 +171,7 @@ make \
 		(!attr.SkipCheckEarly || !t.stage.isStage0()) {
 		scriptMake += attr.ScriptCheckEarly + `make \
 	` + jobsFlagE + ` \
+	` + loadFlagE + ` \
 	`
 		if len(attr.Check) > 0 {
 			scriptMake += strings.Join(attr.Check, " \\\n\t")

internal/rosa/meson.go

@@ -5,10 +5,16 @@ import (
 	"strings"
 )
 
-var _meson = H("meson")
+var (
+	_muon  = H("muon")
+	_meson = H("meson")
+)
 
 // MesonHelper builds and tests a meson project.
 type MesonHelper struct {
+	// Use muon instead of meson.
+	Muon bool
+
 	// Runs after setup.
 	ScriptCompileEarly string
 	// Runs after compile.
@@ -18,6 +24,8 @@ type MesonHelper struct {
 
 	// Flags passed to the setup command.
 	Setup []KV
+	// Test suites to skip.
+	SkipTests []string
 	// Whether to skip meson test.
 	SkipTest bool
 	// Run tests with interactive input/output.
@@ -27,7 +35,12 @@ type MesonHelper struct {
 var _ Helper = new(MesonHelper)
 
 // extra returns hardcoded meson runtime dependencies.
-func (*MesonHelper) extra(int) P { return P{_meson} }
+func (attr *MesonHelper) extra(int) P {
+	if !attr.isPython() {
+		return P{_muon}
+	}
+	return P{_meson}
+}
 
 // wantsChmod returns false.
 func (*MesonHelper) wantsChmod() bool { return false }
@@ -41,6 +54,12 @@ func (*MesonHelper) scriptEarly() string { return "" }
 // wantsDir requests a new directory in TMPDIR.
 func (*MesonHelper) wantsDir() (string, bool) { return `"$(mktemp -d)"`, false }
 
+// isPython returns whether the legacy python implementation is used.
+func (attr *MesonHelper) isPython() bool {
+	return attr == nil ||
+		!attr.Muon || len(attr.SkipTests) != 0 || attr.InteractiveTest
+}
+
 // script generates the cure script.
 func (attr *MesonHelper) script(t Toolchain, name string) string {
 	if attr == nil {
@@ -52,41 +71,57 @@ func (attr *MesonHelper) script(t Toolchain, name string) string {
 		scriptCompiled = "\n" + scriptCompiled
 	}
 
+	python := attr.isPython()
+	muon := "muon"
+	compile := " samu " + jobsFlagE
+	destdir := "-d"
+	if python {
+		muon = "meson"
+		compile = " compile " + jobsFlagE + " " + loadFlagE
+		destdir = "--destdir"
+	}
+
 	var scriptTest string
 	if !attr.SkipTest && t.opts&OptSkipCheck == 0 {
 		scriptTest = `
-meson test \
+` + muon + ` test \
+	` + jobsFlagE + ` \
+	-t 10`
+		if python {
+			scriptTest += ` \
 	--print-errorlogs`
+		} else {
+			scriptTest += " -Rv"
+		}
 		if attr.InteractiveTest {
 			scriptTest += ` \
 	--interactive`
 		}
+		for _, suite := range attr.SkipTests {
+			scriptTest += " \\\n\t--no-suite='" + suite + "'"
+		}
 	}
 
 	return `
-cd "$(mktemp -d)"
+` + muon + ` setup \
-meson setup \
 	` + strings.Join(slices.Collect(func(yield func(string) bool) {
 		for _, v := range append([]KV{
-			{"wrap-mode", "nofallback"},
+			{"wrap_mode", "nofallback"},
 			{"prefix", "/system"},
 			{"buildtype", "release"},
 		}, attr.Setup...) {
-			s := "-" + v[0]
+			s := v[0]
-			if len(v[0]) > 0 && v[0][0] != 'D' {
-				s = "-" + s
-			}
 			if v[1] != "" {
-				s += "=" + v[1]
+				s = "-D" + s + "=" + v[1]
 			}
 			if !yield(s) {
 				return
 			}
 		}
 	}), " \\\n\t") + ` \
-	. '/usr/src/` + name + `'
+	'/usr/src/` + name + `'
-meson compile` + scriptCompiled + scriptTest + `
+` + muon + compile + scriptCompiled + scriptTest + `
-meson install \
+` + muon + ` install \
-	--destdir=/work
+	` + destdir + ` /work
 ` + attr.Script
 }

internal/rosa/mirror.go

@@ -14,6 +14,7 @@ import (
 	"path/filepath"
 	"strconv"
 	"strings"
+	"syscall"
 	"unique"
 
 	"hakurei.app/internal/pkg"
@@ -30,8 +31,8 @@ type Remote struct {
 	c *http.Client
 }
 
-// NewRemote returns a populated [Remote]
+// NewRemote returns a populated [Remote].
-func NewRemote(base string, pub ed25519.PublicKey, c *http.Client) (Remote, error) {
+func NewRemote(c *http.Client, base string, pub ed25519.PublicKey) (Remote, error) {
 	u, err := url.Parse(base)
 	return Remote{u, pub, c}, err
 }
@@ -201,14 +202,261 @@ func (r Remote) Status(
 	), nil
 }
 
-// NewMirror returns an [http.Handler] for servicing mirror requests.
+// Mirror services requests made by [Remote].
+type Mirror struct {
+	// Cache on-filesystem format.
+	fsys fs.FS
+	// Signs payloads.
+	key ed25519.PrivateKey
+	// Verbose output.
+	msg message.Msg
+}
+
+// Populate fills an empty root with a static mirror snapshot.
+func (m Mirror) Populate(root *os.Root) error {
+	if dents, err := fs.ReadDir(root.FS(), "."); err != nil {
+		return err
+	} else if len(dents) > 0 {
+		return syscall.ENOTEMPTY
+	}
+
+	for _, name := range []string{
+		dirArtifact,
+		dirOutcome,
+		dirStatus,
+	} {
+		if err := root.Mkdir(name, 0755); err != nil {
+			return err
+		}
+	}
+	var w *os.File
+
+	if dents, err := fs.ReadDir(m.fsys, "identifier"); err != nil {
+		return err
+	} else {
+		for _, dent := range dents {
+			name := dent.Name()
+			var buf [2 * len(pkg.Checksum{})]byte
+			if err = pkg.Decode(
+				(*pkg.Checksum)(buf[:len(pkg.Checksum{})]),
+				name,
+			); err != nil {
+				return err
+			}
+
+			if w, err = root.OpenFile(
+				filepath.Join(dirArtifact, name),
+				syscall.O_WRONLY|syscall.O_CREAT|syscall.O_EXCL,
+				0444,
+			); err != nil {
+				return err
+			}
+			err = m.writeArtifact(&buf, w, nil)
+			if err = errors.Join(err, w.Close()); err != nil {
+				return err
+			}
+		}
+	}
+
+	if dents, err := fs.ReadDir(m.fsys, "checksum"); err != nil {
+		return err
+	} else {
+		for _, dent := range dents {
+			name := dent.Name()
+			var buf pkg.Checksum
+			if err = pkg.Decode(&buf, name); err != nil {
+				return err
+			}
+
+			var fsys fs.FS
+			fsys, err = fs.Sub(m.fsys, filepath.Join("checksum", name))
+			if err != nil {
+				return err
+			}
+
+			if w, err = root.OpenFile(
+				filepath.Join(dirOutcome, name),
+				syscall.O_WRONLY|syscall.O_CREAT|syscall.O_EXCL,
+				0444,
+			); err != nil {
+				return err
+			}
+
+			m.msg.Verbosef("exporting outcome %s", name)
+			err = pkg.Write(fsys, ".", w)
+			if err = errors.Join(err, w.Close()); err != nil {
+				return err
+			}
+		}
+	}
+
+	if dents, err := fs.ReadDir(m.fsys, "status"); err != nil {
+		return err
+	} else {
+		for _, dent := range dents {
+			name := dent.Name()
+			var buf [2 * len(pkg.Checksum{})]byte
+			if err = pkg.Decode(
+				(*pkg.Checksum)(buf[:len(pkg.Checksum{})]),
+				name,
+			); err != nil {
+				return err
+			}
+
+			if w, err = root.OpenFile(
+				filepath.Join(dirStatus, name),
+				syscall.O_WRONLY|syscall.O_CREAT|syscall.O_EXCL,
+				0444,
+			); err != nil {
+				return err
+			}
+			err = m.writeStatus(&buf, w, nil)
+			if err = errors.Join(err, w.Close()); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+// NewMirror returns a populated [Mirror] for servicing mirror requests.
 func NewMirror(
 	msg message.Msg,
 	fsys fs.FS,
 	key ed25519.PrivateKey,
-) http.Handler {
+) Mirror {
+	return Mirror{fsys, key, msg}
+}
+
+// writeArtifact writes a signed dirArtifact response.
+func (m Mirror) writeArtifact(
+	buf *[2 * len(pkg.Checksum{})]byte,
+	w io.Writer,
+	header http.Header,
+) error {
+	ids := pkg.Encode((pkg.Checksum)(buf[:len(pkg.Checksum{})]))
+	if linkname, err := fs.ReadLink(m.fsys, filepath.Join(
+		"identifier",
+		ids,
+	)); err != nil {
+		return err
+	} else if err = pkg.Decode(
+		(*pkg.Checksum)(buf[len(pkg.Checksum{}):]),
+		filepath.Base(linkname),
+	); err != nil {
+		return err
+	}
+	m.msg.Verbosef("serving artifact %s", ids)
+
+	if header != nil {
+		header.Set(
+			"Content-Length",
+			strconv.Itoa(ed25519.SignatureSize+len(buf)),
+		)
+	}
+	_, err := w.Write(append(ed25519.Sign(m.key, buf[:]), buf[:]...))
+	return err
+}
+
+// writeOutcome writes a dirOutcome response.
+func (m Mirror) writeOutcome(
+	buf *pkg.Checksum,
+	w io.Writer,
+	header http.Header,
+) error {
+	checksums := pkg.Encode(*buf)
+	rel := filepath.Join("checksum", checksums)
+	if _, err := fs.Lstat(m.fsys, rel); err != nil {
+		return err
+	}
+	m.msg.Verbosef("serving outcome %s", checksums)
+
+	_fsys, err := fs.Sub(m.fsys, rel)
+	if err != nil {
+		return err
+	}
+
+	var gw *gzip.Writer
+	if gw, err = gzip.NewWriterLevel(w, gzip.BestCompression); err != nil {
+		return err
+	}
+	if header != nil {
+		header.Set("Content-Encoding", "gzip")
+	}
+	if err = pkg.Write(_fsys, ".", gw); err != nil {
+		_ = gw.Close()
+		return err
+	}
+	return gw.Close()
+}
+
+// writeStatus writes a signed dirStatus response.
+func (m Mirror) writeStatus(
+	buf *[2 * len(pkg.Checksum{})]byte,
+	w io.Writer,
+	_ http.Header,
+) error {
+	ids := pkg.Encode((pkg.Checksum)(buf[:len(pkg.Checksum{})]))
+	f, err := m.fsys.Open(filepath.Join(
+		"status",
+		ids,
+	))
+	if err != nil {
+		return err
+	}
+	s, ok := f.(io.Seeker)
+	if !ok {
+		return &fs.PathError{Op: "seek", Path: ids, Err: fs.ErrInvalid}
+	}
+	m.msg.Verbosef("serving status %s", ids)
+
+	h := sha512.New384()
+	if _, err = io.Copy(h, f); err != nil {
+		_ = f.Close()
+		return err
+	}
+	h.Sum(buf[len(pkg.Checksum{}):len(pkg.Checksum{})])
+	if _, err = w.Write(append(ed25519.Sign(m.key, buf[:]), buf[:]...)); err != nil {
+		_ = f.Close()
+		return err
+	} else if _, err = s.Seek(0, io.SeekStart); err != nil {
+		_ = f.Close()
+		return err
+	} else if _, err = io.Copy(w, f); err != nil {
+		_ = f.Close()
+		return err
+	}
+	return f.Close()
+}
+
+// writeF is a helper for writing a mirror response with error handling.
+func writeF[B any](
+	m Mirror,
+	w http.ResponseWriter,
+	buf B,
+	f func(
+		buf B,
+		w io.Writer,
+		header http.Header,
+	) error,
+) {
+	err := f(buf, w, w.Header())
+	if err == nil {
+		return
+	}
+
+	if errors.Is(err, os.ErrNotExist) {
+		w.WriteHeader(http.StatusNotFound)
+		return
+	}
+	m.msg.GetLogger().Println(err)
+	w.WriteHeader(http.StatusInternalServerError)
+}
+
+// Register configures an [http.ServeMux] for servicing mirror requests.
+func (m Mirror) Register(mux *http.ServeMux) {
 	const identName = "ident"
-	var mux http.ServeMux
 
 	mux.HandleFunc("/"+dirArtifact+"/{"+identName+"}", func(
 		w http.ResponseWriter,
@@ -222,38 +470,7 @@ func NewMirror(
 			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
-
+		writeF(m, w, &buf, m.writeArtifact)
-		ids := pkg.Encode((pkg.Checksum)(buf[:len(pkg.Checksum{})]))
-		if linkname, err := fs.ReadLink(fsys, filepath.Join(
-			"identifier",
-			ids,
-		)); err != nil {
-			if errors.Is(err, os.ErrNotExist) {
-				w.WriteHeader(http.StatusNotFound)
-				return
-			}
-			msg.GetLogger().Println(err)
-			w.WriteHeader(http.StatusInternalServerError)
-			return
-		} else if err = pkg.Decode(
-			(*pkg.Checksum)(buf[len(pkg.Checksum{}):]),
-			filepath.Base(linkname),
-		); err != nil {
-			http.Error(w, err.Error(), http.StatusInternalServerError)
-			return
-		}
-		msg.Verbosef("serving artifact %s", ids)
-
-		w.Header().Set(
-			"Content-Length",
-			strconv.Itoa(ed25519.SignatureSize+len(buf)),
-		)
-		if _, err := w.Write(append(
-			ed25519.Sign(key, buf[:]),
-			buf[:]...,
-		)); err != nil {
-			msg.Verbose(err)
-		}
 	})
 
 	mux.HandleFunc("/"+dirOutcome+"/{"+identName+"}", func(
@@ -273,40 +490,7 @@ func NewMirror(
 			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
-
+		writeF(m, w, &buf, m.writeOutcome)
-		checksums := pkg.Encode(buf)
-		rel := filepath.Join("checksum", checksums)
-		if _, err := fs.Lstat(fsys, rel); err != nil {
-			if errors.Is(err, os.ErrNotExist) {
-				w.WriteHeader(http.StatusNotFound)
-				return
-			}
-			msg.GetLogger().Println(err)
-			w.WriteHeader(http.StatusInternalServerError)
-			return
-		}
-		msg.Verbosef("serving outcome %s", pkg.Encode(buf))
-
-		_fsys, err := fs.Sub(fsys, rel)
-		if err != nil {
-			msg.GetLogger().Println(err)
-			w.WriteHeader(http.StatusInternalServerError)
-			return
-		}
-
-		var gw *gzip.Writer
-		if gw, err = gzip.NewWriterLevel(w, gzip.BestCompression); err != nil {
-			msg.GetLogger().Println(err)
-			w.WriteHeader(http.StatusInternalServerError)
-			return
-		}
-		w.Header().Set("Content-Encoding", "gzip")
-		if err = pkg.Write(_fsys, ".", gw); err != nil {
-			msg.Verbose(err)
-		}
-		if err = gw.Close(); err != nil {
-			msg.GetLogger().Println(err)
-		}
 	})
 
 	mux.HandleFunc("/"+dirStatus+"/{"+identName+"}", func(
@@ -321,47 +505,6 @@ func NewMirror(
 			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
-
+		writeF(m, w, &buf, m.writeStatus)
-		ids := pkg.Encode((pkg.Checksum)(buf[:len(pkg.Checksum{})]))
-		f, err := fsys.Open(filepath.Join(
-			"status",
-			ids,
-		))
-		if err != nil {
-			if errors.Is(err, os.ErrNotExist) {
-				w.WriteHeader(http.StatusNotFound)
-				return
-			}
-			msg.GetLogger().Println(err)
-			w.WriteHeader(http.StatusInternalServerError)
-			return
-		}
-		s, ok := f.(io.Seeker)
-		if !ok {
-			msg.GetLogger().Println("backing filesystem does not support seek")
-			w.WriteHeader(http.StatusInternalServerError)
-			return
-		}
-		msg.Verbosef("serving status %s", ids)
-
-		h := sha512.New384()
-		if _, err = io.Copy(h, f); err != nil {
-			_ = f.Close()
-			msg.Verbose(err)
-			w.WriteHeader(http.StatusInternalServerError)
-		}
-		h.Sum(buf[len(pkg.Checksum{}):len(pkg.Checksum{})])
-		if _, err = w.Write(append(ed25519.Sign(key, buf[:]), buf[:]...)); err != nil {
-			msg.Verbose(err)
-			return
-		} else if _, err = s.Seek(0, io.SeekStart); err != nil {
-			msg.GetLogger().Println(err)
-			return
-		} else if _, err = io.Copy(w, f); err != nil {
-			msg.Verbose(err)
-			return
-		}
 	})
-
-	return &mux
 }

internal/rosa/mirror_test.go

@@ -4,6 +4,7 @@ import (
 	"crypto/ed25519"
 	"io/fs"
 	"log"
+	"net/http"
 	"net/http/httptest"
 	"os"
 	"testing"
@@ -30,7 +31,7 @@ func TestMirror(t *testing.T) {
 	msg.SwapVerbose(testing.Verbose())
 
 	var c *pkg.Cache
-	c, err = pkg.Open(t.Context(), msg, 0, 0, 0, base)
+	c, err = pkg.Open(t.Context(), msg, base, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -52,14 +53,16 @@ func TestMirror(t *testing.T) {
 	}
 	wantChecksums := pkg.Encode(wantChecksum)
 
-	server := httptest.NewServer(rosa.NewMirror(msg, fstest.MapFS{
+	var mux http.ServeMux
+	rosa.NewMirror(msg, fstest.MapFS{
 		"identifier/" + ids:         {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantChecksums)},
 		"checksum/" + wantChecksums: {Mode: os.ModeDir | 0500},
-	}, priv))
+	}, priv).Register(&mux)
+	server := httptest.NewServer(&mux)
 	t.Cleanup(server.Close)
 
 	var extern pkg.External
-	extern, err = rosa.NewRemote("http://example.com:80", pub, server.Client())
+	extern, err = rosa.NewRemote(server.Client(), "http://example.com:80", pub)
 	if err != nil {
 		t.Fatal(err)
 	}

internal/rosa/package/acl/libgen-basename.patch

@@ -1,26 +0,0 @@
-From 8a80d895dfd779373363c3a4b62ecce5a549efb2 Mon Sep 17 00:00:00 2001
-From: "Haelwenn (lanodan) Monnier" <contact@hacktivis.me>
-Date: Sat, 30 Mar 2024 10:17:10 +0100
-Subject: tools/attr.c: Add missing libgen.h include for basename(3)
-
-Fixes compilation issue with musl and modern C99 compilers.
-
-See: https://bugs.gentoo.org/926294
----
- tools/attr.c | 1 +
- 1 file changed, 1 insertion(+)
-
-diff --git a/tools/attr.c b/tools/attr.c
-index f12e4af..6a3c1e9 100644
---- a/tools/attr.c
-+++ b/tools/attr.c
-@@ -28,6 +28,7 @@
- #include <errno.h>
- #include <string.h>
- #include <locale.h>
-+#include <libgen.h>
- 
- #include <attr/attributes.h>
- 
--- 
-cgit v1.1

internal/rosa/package/acl/musl-errno.patch

@@ -1,7 +1,7 @@
-diff --git a/test/attr.test b/test/attr.test
+diff --git a/test/attr.run b/test/attr.run
-index 6ce2f9b..e9bde92 100644
+index 27d17f6..a4d60c0 100644
---- a/test/attr.test
+--- a/test/attr.run
-+++ b/test/attr.test
++++ b/test/attr.run
 @@ -11,7 +11,7 @@ Try various valid and invalid names
  
  	$ touch f

internal/rosa/package/acl/package.az

@@ -3,25 +3,25 @@ package attr {
 	website = "https://savannah.nongnu.org/projects/attr";
 	anitya = 137;
 
-	version# = "2.5.2";
+	version# = "2.6.0";
 	source = remoteTar {
 		url = "https://download.savannah.nongnu.org/releases/attr/"+
 			"attr-"+version+".tar.gz";
-		checksum = "YWEphrz6vg1sUMmHHVr1CRo53pFXRhq_pjN-AlG8UgwZK1y6m7zuDhxqJhD0SV0l";
+		checksum = "pp-NvD1cMIwZycNwZGW2ez-PbTEpHxrRnVH27csj9QdN4oEBkEbJOZX1IIvKnTWS";
 		compress = gzip;
 	};
-	patches = [
-		"libgen-basename.patch",
-		"musl-errno.patch",
-	];
 
-	early = `
+	patches = [ "musl-errno.patch" ];
-ln -s ../../system/bin/perl /usr/bin
-`;
 
+	bin = [ "perl" ];
+	populateUsrBin = true;
 	exec = make {};
 
-	inputs = [ perl ];
+	inputs = [
+		perl,
+
+		kernel-headers,
+	];
 }
 
 package acl {
@@ -29,11 +29,11 @@ package acl {
 	website = "https://savannah.nongnu.org/projects/acl";
 	anitya = 16;
 
-	version# = "2.3.2";
+	version# = "2.4.0";
 	source = remoteTar {
 		url = "https://download.savannah.nongnu.org/releases/acl/"+
 			"acl-"+version+".tar.gz";
-		checksum = "-fY5nwH4K8ZHBCRXrzLdguPkqjKI6WIiGu4dBtrZ1o0t6AIU73w8wwJz_UyjIS0P";
+		checksum = "U2eaAsWrhhzEfhyprwHQQG55bFPZxtsHk1Usnd9Jb_g-H__pJod4H3RTrL4ipXDw";
 		compress = gzip;
 	};
 
@@ -42,6 +42,6 @@ package acl {
 		skipCheck = true;
 	};
 
-	inputs = [ attr ];
+	inputs = [ attr, kernel-headers ];
 	runtime = [ attr ];
 }

internal/rosa/package/awk.az

@@ -0,0 +1,31 @@
+package awk {
+	description = "one true awk";
+	website = "https://github.com/onetrueawk/awk";
+	anitya = 16171;
+
+	version# = "20260426";
+	source = remoteGitHub {
+		suffix = "onetrueawk/awk";
+		tag = version;
+		checksum = "ewAvWLEHajhm7cA7v4DsKVk1c11niCLKIE5Q-8W_sxv1XXsbZlcOuWn1KOBYMxjo";
+	};
+
+	enterSource = true;
+	writable = true;
+	chmod = true;
+
+	exec = make {
+		omitDefaults = true;
+		inPlace = true;
+		skipConfigure = true;
+		make = [ "YACC='yacc -d -b awkgram'" ];
+		preCheck = "install -vD a.out /system/bin/awk\n";
+		install = "install -vD a.out /work/system/bin/awk";
+	};
+
+	inputs = [
+		m4,
+		byacc,
+		diffutils,
+	];
+}

internal/rosa/package/bison.az

@@ -14,6 +14,8 @@ package bison {
 		check = [
 			"TESTSUITEFLAGS=" + jobsFlagE + "' " + skipGNUTests {
 				tests = [
+					// GNU-isms not implemented in toybox
+					168, 170, 623,
 					// clang miscompiles (SIGILL)
 					764,
 				];
@@ -22,9 +24,6 @@ package bison {
 		];
 	};
 
-	inputs = [
+	toyboxEarly = true;
-		m4,
+	inputs = [ m4 ];
-		diffutils,
-		sed,
-	];
 }

internal/rosa/package/byacc.az

@@ -0,0 +1,22 @@
+package byacc {
+	description = "Berkeley Yacc";
+	website = "https://invisible-island.net/byacc";
+	anitya = 233;
+
+	version# = "20260126";
+	source = remoteTar {
+		url = "https://invisible-island.net/archives/byacc/"+
+			"byacc-"+version+".tgz";
+		compress = gzip;
+		checksum = "3IXzewZmFUW3hkFKBuweR0hUSftlI2zE0lBZf16I8oK3mFEyj51FzVv1wvA12uoC";
+	};
+
+	// awk dependency loop
+	toyboxEarly = true;
+
+	// test suite assumes writable source
+	writable = true;
+	chmod = true;
+
+	exec = make {};
+}

internal/rosa/package/cairo.az

@@ -13,16 +13,16 @@ package cairo {
 
 	exec = meson {
 		setup = {
-			"Ddwrite": "enabled";
+			"dwrite": "enabled";
-			"Dfontconfig": "enabled";
+			"fontconfig": "enabled";
-			"Dfreetype": "enabled";
+			"freetype": "enabled";
 
-			"Dpng": "enabled";
+			"png": "enabled";
-			"Dtee": "enabled";
+			"tee": "enabled";
-			"Dxcb": "enabled";
+			"xcb": "enabled";
-			"Dxlib": "disabled";
+			"xlib": "disabled";
-			"Dxlib-xcb": "disabled";
+			"xlib-xcb": "disabled";
-			"Dzlib": "enabled";
+			"zlib": "enabled";
 		};
 		// runs the entire test suite in a single meson test
 		interactiveTest = true;
@@ -31,7 +31,7 @@ package cairo {
 	};
 
 	inputs = [
-		gawk,
+		awk,
 
 		zlib,
 		libpng,

internal/rosa/package/cmake/bootstrap-test-no-openssl.patch

@@ -1,13 +0,0 @@
-diff --git a/Tests/BootstrapTest.cmake b/Tests/BootstrapTest.cmake
-index 137de78bc1..b4da52e664 100644
---- a/Tests/BootstrapTest.cmake
-+++ b/Tests/BootstrapTest.cmake
-@@ -9,7 +9,7 @@ if(NOT nproc EQUAL 0)
- endif()
- message(STATUS "running bootstrap: ${bootstrap} ${ninja_arg} ${parallel_arg}")
- execute_process(
--  COMMAND ${bootstrap} ${ninja_arg} ${parallel_arg}
-+  COMMAND ${bootstrap} ${ninja_arg} ${parallel_arg} -- -DCMAKE_USE_OPENSSL=OFF
-   WORKING_DIRECTORY "${bin_dir}"
-   RESULT_VARIABLE result
-   )

internal/rosa/package/cmake/package.az

@@ -3,18 +3,15 @@ package cmake {
 	website = "https://cmake.org";
 	anitya = 306;
 
-	version# = "4.3.3";
+	version# = "4.4.0";
 	source = remoteGitHubRelease {
 		suffix = "Kitware/CMake";
 		tag = "v"+version;
 		name = "cmake-"+version+".tar.gz";
-		checksum = "VS-b6cN4S9hfNv3JOUAbAfI9nh3EeuVwY_IVgUdgq6VKwvfchhXwvvFAUcpZG6Ez";
+		checksum = "ZL0Y19_mSJWsl3dMjRRQJAaCvl4_PqbwpgUC1aBA-cdVdrK_gt4ylpUM2GMoQMku";
 		compress = gzip;
 	};
-	patches = [
+	patches = [ "disable-broken-tests-musl.patch" ];
-		"bootstrap-test-no-openssl.patch",
-		"disable-broken-tests-musl.patch",
-	];
 
 	// test suite expects writable source tree
 	writable = true;
@@ -32,6 +29,7 @@ package cmake {
 			"--";
 			"-DCMAKE_USE_OPENSSL": "OFF";
 			"-DCMake_TEST_NO_NETWORK": "ON";
+			"-DCMake_TEST_BOOTSTRAP": "OFF";
 		};
 
 		check = [

internal/rosa/package/curl.az

@@ -3,10 +3,10 @@ package curl {
 	website = "https://curl.se";
 	anitya = 381;
 
-	version# = "8.20.0";
+	version# = "8.21.0";
 	source = remoteTar {
 		url = "https://curl.se/download/curl-"+version+".tar.bz2";
-		checksum = "xyHXwrngIRGMasuzhn-I5MSCOhktwINbsWt1f_LuR-5jRVvyx_g6U1EQfDLEbr9r";
+		checksum = "lJSm8bVjS0OmsarEdbvejdQdvXsb7yGarlr6oMtA9FW1EXOga8zZxa1LPtfaq_qX";
 		compress = bzip2;
 	};
 

internal/rosa/package/dbus.az

@@ -19,9 +19,9 @@ package dbus {
 
 	exec = meson {
 		setup = {
-			"Depoll": "enabled";
+			"epoll": "enabled";
-			"Dinotify": "enabled";
+			"inotify": "enabled";
-			"Dx11_autolaunch": "disabled";
+			"x11_autolaunch": "disabled";
 		};
 	};
 
@@ -50,7 +50,7 @@ package xdg-dbus-proxy {
 
 	exec = meson {
 		setup = {
-			"Dman": "disabled";
+			"man": "disabled";
 		};
 	};
 

internal/rosa/package/dtc.az

@@ -18,7 +18,7 @@ package dtc {
 
 	exec = meson {
 		setup = {
-			"Dyaml": "disabled";
+			"yaml": "disabled";
 		};
 	};
 

internal/rosa/package/fcft.az

@@ -5,8 +5,9 @@ package fcft {
 
 	version# = "3.3.3";
 	source = remoteTar {
-		url = "https://codeberg.org/dnkl/fcft/archive/"+version+".tar.gz";
+		url = "https://codeberg.org/dnkl/fcft/releases/download/"+version+
-		checksum = "bMj8OmqtoANRKZWbjHk4WfP09AxJYRbWGqUsm1gRJ_dOFg6gooNbgkDu597PLfz2";
+			"/fcft-"+version+".tar.gz";
+		checksum = "pryAJA-d1OpY8KXbGFEHum9Wm6ME9XkPx9EM_OQ_ZEpOUpQnqlkzIq-cwS1ziMPk";
 		compress = gzip;
 	};
 

internal/rosa/package/firmware.az

@@ -3,12 +3,12 @@ package firmware {
 	website = "https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git";
 	anitya = 141464;
 
-	version# = "20260519";
+	version# = "20260622";
 	source = remoteGitLab {
 		domain = "gitlab.com";
 		suffix = "kernel-firmware/linux-firmware";
 		ref = version;
-		checksum = "l-wBRTWclYnJsgV4qtUV1-UL5Y4nknAPre8CMe0dH7PxtAqbaeudEIM_Fnuj0TCV";
+		checksum = "gpytkDM58EVjaUuryOekcekh_rWsfuv3S7LQxopHlNlVGmMsuqNwfug4BjgTgizE";
 	};
 
 	// dedup creates temporary file
@@ -34,7 +34,7 @@ package firmware {
 		// requires pre-commit
 		skipCheck = true;
 
-		install = "make " + jobsFlagE + " DESTDIR=/work/system dedup";
+		install = "make " + jobsFlagE + " " + loadFlagE + " DESTDIR=/work/system dedup";
 	};
 
 	inputs = [

internal/rosa/package/fontconfig.az

@@ -3,12 +3,12 @@ package fontconfig {
 	website = "https://www.freedesktop.org/wiki/Software/fontconfig";
 	anitya = 827;
 
-	version# = "2.18.1";
+	version# = "2.18.2";
 	source = remoteGitLab {
 		domain = "gitlab.freedesktop.org";
 		suffix = "fontconfig/fontconfig";
 		ref = version;
-		checksum = "S3FJfh-PeZ2_YgNrUqL0H2G4Wf_ilj5HpIGV2oURnkK672AQHpWk526bNtRHwyJt";
+		checksum = "P8YoQunIynBhc3gdDyPkImw_GGYoy1U4aX0jTnpkgtLmU4nqIgUyeqCH3-rNzpTd";
 	};
 
 	exec = make {

internal/rosa/package/foot.az

@@ -5,8 +5,9 @@ package foot {
 
 	version# = "1.27.0";
 	source = remoteTar {
-		url = "https://codeberg.org/dnkl/foot/archive/"+version+".tar.gz";
+		url = "https://codeberg.org/dnkl/foot/releases/download/"+version+
-		checksum = "E2XIPRD8t-WBBJUebIwChFT8K_85diwdalssUNwnuZBIynPa7rlXro5WCe9v3UlK";
+			"/foot-"+version+".tar.gz";
+		checksum = "22rG3rMuQI8Ae2XTcZgOJ-6AbF7Taex8XpgvD6Fyg1Mn5Va67FfUcK3tRaq61TFg";
 		compress = gzip;
 	};
 

internal/rosa/package/fribidi.az

@@ -12,7 +12,7 @@ package fribidi {
 
 	exec = meson {
 		setup = {
-			"Ddocs": "false";
+			"docs": "false";
 		};
 	};
 }

internal/rosa/package/fuse.az

@@ -14,10 +14,10 @@ package fuse {
 
 	exec = meson {
 		setup = {
-			"Ddefault_library": "both";
+			"default_library": "both";
-			"Dtests": "true";
+			"tests": "true";
-			"Duseroot": "false";
+			"useroot": "false";
-			"Dinitscriptdir": "/system/etc";
+			"initscriptdir": "/system/etc";
 		};
 
 		postCompile = "python3 -m pytest test/";

internal/rosa/package/gawk/broken-tests.patch

@@ -0,0 +1,35 @@
+diff --git a/test/Makefile.am b/test/Makefile.am
+index 88e15ef1f..bfc279fcb 100644
+--- a/test/Makefile.am
++++ b/test/Makefile.am
+@@ -1726,7 +1726,7 @@ LOCALE_CHARSET_TESTS = \
+ SHLIB_TESTS = \
+ 	apiterm filefuncs fnmatch fork fork2 fts functab4 functab5 \
+ 	getfile indirectbuiltin2 inplace1 inplace2 inplace2bcomp inplace3 \
+-	inplace3bcomp ordchr ordchr2 readall readdir readdir_retest \
++	inplace3bcomp ordchr ordchr2 readall readdir_retest \
+ 	readdir_test readfile readfile2 revout revtwoway rwarray \
+ 	testext time
+ 
+diff --git a/test/Makefile.in b/test/Makefile.in
+index 2d4eeaa5a..7930af8d5 100644
+--- a/test/Makefile.in
++++ b/test/Makefile.in
+@@ -1986,7 +1986,7 @@ LOCALE_CHARSET_TESTS = \
+ SHLIB_TESTS = \
+ 	apiterm filefuncs fnmatch fork fork2 fts functab4 functab5 \
+ 	getfile indirectbuiltin2 inplace1 inplace2 inplace2bcomp inplace3 \
+-	inplace3bcomp ordchr ordchr2 readall readdir readdir_retest \
++	inplace3bcomp ordchr ordchr2 readall readdir_retest \
+ 	readdir_test readfile readfile2 revout revtwoway rwarray \
+ 	testext time
+ 
+diff --git a/test/clos1way6.ok b/test/clos1way6.ok
+index 5768617d3..be4d73e79 100644
+--- a/test/clos1way6.ok
++++ b/test/clos1way6.ok
+@@ -1,3 +1,3 @@
+ gawk: clos1way6.awk:5: warning: fflush: cannot flush: two-way pipe `cat - 1>&2; sleep 2' has closed write end
+-test1
+ Bad file descriptor
++test1

internal/rosa/package/gawk/musl-errno.patch

@@ -0,0 +1,39 @@
+diff --git a/test/testext-mpfr.ok b/test/testext-mpfr.ok
+index 6a5f98147..adf8685e2 100644
+--- a/test/testext-mpfr.ok
++++ b/test/testext-mpfr.ok
+@@ -21,7 +21,7 @@ var_test: sym_update of ARGC failed - correctly
+ var_test: sym_update("testvar") succeeded
+ var_test() returned 1, test_var = 42
+ 
+-test_errno() returned 1, ERRNO = No child processes
++test_errno() returned 1, ERRNO = No child process
+ 
+ fubar = 9
+ rumpus = -5
+diff --git a/test/testext.ok b/test/testext.ok
+index 3e0c1328c..11d150fe3 100644
+--- a/test/testext.ok
++++ b/test/testext.ok
+@@ -21,7 +21,7 @@ var_test: sym_update of ARGC failed - correctly
+ var_test: sym_update("testvar") succeeded
+ var_test() returned 1, test_var = 42
+ 
+-test_errno() returned 1, ERRNO = No child processes
++test_errno() returned 1, ERRNO = No child process
+ 
+ fubar = 9
+ rumpus = -5
+diff --git a/vms/vmstest.com b/vms/vmstest.com
+index a042764b1..c47984e38 100644
+--- a/vms/vmstest.com
++++ b/vms/vmstest.com
+@@ -917,7 +917,7 @@ $	set noOn
+ $	AWKLIBPATH_dir
+ $	gawk -f _'test'.awk >_'test'.tmp 2>&1
+ $	if .not. $status then call exit_code '$status' _'test'.tmp
+-$	gawk "{gsub(""no children"",""No child processes"")}1" -
++$	gawk "{gsub(""no children"",""No child process"")}1" -
+ 	    _'test'.tmp >_'test'.tmp1
+ $	rm sys$disk:[]_'test'.tmp;*
+ $	mv sys$disk:[]_'test'.tmp1 sys$disk:[]_'test'.tmp

internal/rosa/package/gawk/package.az

@@ -0,0 +1,26 @@
+package gawk {
+	description = "an implementation of awk with GNU extensions";
+	website = "https://www.gnu.org/software/gawk";
+	anitya = 868;
+
+	block = "regressions introduced in 5.4.1, "+
+		"does not even pass its own test suite";
+
+	version# = "5.4.0";
+	source = remoteTar {
+		url = "https://ftpmirror.gnu.org/gnu/gawk/gawk-"+version+".tar.gz";
+		checksum = "m0RkIolC-PI7EY5q8pcx5Y-0twlIW0Yp3wXXmV-QaHorSdf8BhZ7kW9F8iWomz0C";
+		compress = gzip;
+	};
+	patches = [
+		"musl-errno.patch",
+		"broken-tests.patch",
+	];
+
+	exec = make {};
+
+	inputs = [
+		diffutils,
+		util-linux,
+	];
+}

internal/rosa/package/gcc/package.az

@@ -82,6 +82,7 @@ ln -s system/lib /work/
 
 		mpc,
 		zlib,
+		zstd,
 		libucontext,
 	];
 }

internal/rosa/package/git.az

@@ -3,24 +3,25 @@ package git {
 	website = "https://www.git-scm.com";
 	anitya = 5350;
 
-	version# = "2.54.0";
+	version# = "2.55.0";
 	source = remoteTar {
 		url = "https://www.kernel.org/pub/software/scm/git/"+
 			"git-"+version+".tar.gz";
-		checksum = "7vGKtFOJGqY8DO4e8UMRax7dLgImXKQz5MMalec6MlgYrsarffSJjgOughwRFpSH";
+		checksum = "lOer6jb8vZQk6Nd1rLZIgsYys8whLvjJq8XbmCdTATcPFAYuQcK1Rgj1Jj6a00W8";
 		compress = gzip;
 	};
 
 	early = `
-ln -s ../../system/bin/perl /usr/bin/ || true
-
 # test suite assumes apache
 rm -f /system/bin/httpd
 `;
 
 	// uses source tree as scratch space
 	enterSource = true;
+	env = [ "NO_RUST=YesPlease" ];
 
+	bin = [ "perl" ];
+	populateUsrBin = true;
 	exec = make {
 		inPlace = true;
 		generate = "make configure";
@@ -59,6 +60,8 @@ disable_test t1451-fsck-buffer
 disable_test t4104-apply-boundary
 disable_test t4200-rerere
 disable_test t5515-fetch-merge-logic
+disable_test t4124-apply-ws-rule
+disable_test t3404-rebase-interactive
 `;
 
 		check = [
@@ -69,6 +72,7 @@ disable_test t5515-fetch-merge-logic
 
 		install = `make \
 	` + jobsFlagE + ` \
+	` + loadFlagE + ` \
 	DESTDIR=/work \
 	NO_INSTALL_HARDLINKS=1 \
 	install`;
@@ -85,6 +89,7 @@ disable_test t5515-fetch-merge-logic
 		zlib,
 		curl,
 		libexpat,
+		kernel-headers,
 	];
 
 	runtime = [

internal/rosa/package/glib/package.az

@@ -3,11 +3,11 @@ package glib {
 	website = "https://developer.gnome.org/glib";
 	anitya = 10024;
 
-	version# = "2.89.0";
+	version# = "2.89.2";
 	source = remoteGit {
 		url = "https://gitlab.gnome.org/GNOME/glib.git";
 		tag = version;
-		checksum = "4FXKhdS3pC98LevYa_h7piRylG86cZ_c9zAtGr78oHodU1ob8rBxGU0hoIZ4nzcA";
+		checksum = "ZetUwjVOKs0v2xtndzy7_4kvZY2VEESOTT45AAMJVLr22fmTRKit4MJOwruB0als";
 	};
 
 	files = {
@@ -17,8 +17,10 @@ package glib {
 
 	exec = meson {
 		setup = {
-			"Ddefault_library": "both";
+			"default_library": "both";
 		};
+		// fails with ipv6 disabled
+		skipTests = [ "gio" ];
 	};
 
 	inputs = [

internal/rosa/package/glslang.az

@@ -3,11 +3,11 @@ package glslang {
 	website = "https://github.com/KhronosGroup/glslang";
 	anitya = 205796;
 
-	version# = "16.3.0";
+	version# = "16.4.0";
 	source = remoteGitHub {
 		suffix = "KhronosGroup/glslang";
 		tag = version;
-		checksum = "xyqDf8k3-D0_BXHGi0uLgMglnJ05Rf3j73QgbDs3sGtKNdBIQhY8JfqX1NcNoJQN";
+		checksum = "u67ps8Fv_75QDiusvKjzgttPPPxb5V7HsObb0q6OvqQfHh0UGN2_x8Y0RKb9JEie";
 	};
 
 	// test suite writes to source

internal/rosa/package/gnu.az

@@ -19,6 +19,7 @@ chmod +w tests/test-c32ispunct.sh && echo '#!/bin/sh' > tests/test-c32ispunct.sh
 
 	exec = make {};
 
+	toyboxEarly = true;
 	inputs = [
 		diffutils,
 
@@ -102,10 +103,10 @@ package libtool {
 	website = "https://www.gnu.org/software/libtool";
 	anitya = 1741;
 
-	version# = "2.5.4";
+	version# = "2.6.2";
 	source = remoteTar {
 		url = "https://ftpmirror.gnu.org/gnu/libtool/libtool-"+version+".tar.gz";
-		checksum = "pa6LSrQggh8mSJHQfwGjysAApmZlGJt8wif2cCLzqAAa2jpsTY0jZ-6stS3BWZ2Q";
+		checksum = "roFqdjyoGjpK7CWWLJJrTS56LuOQcIdq6Tgr4yplacSwirFHoaiDe6CojIWYinWe";
 		compress = gzip;
 	};
 
@@ -155,6 +156,13 @@ package sed {
 		compress = gzip;
 	};
 
+	writable = true;
+	early = `
+test_disable() { chmod +w "$2" && echo "$1" > "$2"; }
+
+test_disable '#!/bin/sh' testsuite/read-error-stale-errno.sh
+`;
+
 	exec = make {};
 
 	inputs = [
@@ -213,25 +221,6 @@ test_disable '#!/bin/sh' tests/need-filename
 	exec = make {};
 }
 
-package gawk {
-	description = "an implementation of awk with GNU extensions";
-	website = "https://www.gnu.org/software/gawk";
-	anitya = 868;
-
-	version# = "5.4.0";
-	source = remoteTar {
-		url = "https://ftpmirror.gnu.org/gnu/gawk/gawk-"+version+".tar.gz";
-		checksum = "m0RkIolC-PI7EY5q8pcx5Y-0twlIW0Yp3wXXmV-QaHorSdf8BhZ7kW9F8iWomz0C";
-		compress = gzip;
-	};
-
-	toyboxEarly = true;
-	exec = make {
-		// dependency loop
-		skipCheck = true;
-	};
-}
-
 package grep {
 	description = "searches input for lines containing a match to a pattern";
 	website = "https://www.gnu.org/software/grep";
@@ -302,14 +291,18 @@ package findutils {
 	website = "https://www.gnu.org/software/findutils";
 	anitya = 812;
 
-	version# = "4.10.0";
+	version# = "4.11.0";
-	source = remoteFile {
+	source = remoteTar {
 		url = "https://ftpmirror.gnu.org/gnu/findutils/findutils-"+version+".tar.xz";
-		checksum = "ZXABdNBQXL7QjTygynRRTdXYWxQKZ0Wn5eMd3NUnxR0xaS0u0VfcKoTlbo50zxv6";
+		compress = xz;
+		checksum = "X-qsv9aUoBL583q-4iZcBI3_7Ufd3fSIqFmNLXWdEpUihlRfMpGGyAUt8SAvDKae";
 	};
 
+	writable = true;
+	chmod = true;
 	early = `
 echo '#!/bin/sh' > gnulib-tests/test-c32ispunct.sh
+echo 'int main(){return 0;}' > gnulib-tests/test-fstatat.c
 echo 'int main(){return 0;}' > tests/xargs/test-sigusr.c
 `;
 
@@ -317,7 +310,6 @@ echo 'int main(){return 0;}' > tests/xargs/test-sigusr.c
 
 	inputs = [
 		diffutils,
-		xz,
 		sed,
 	];
 }
@@ -363,6 +355,9 @@ test_disable() { chmod +w "$2" && echo "$1" > "$2"; }
 test_disable '#!/bin/sh' gnulib-tests/test-c32ispunct.sh
 test_disable '#!/bin/sh' tests/ls/hyperlink.sh
 test_disable '#!/bin/sh' tests/misc/user.sh
+test_disable '#!/bin/sh' tests/split/line-bytes.sh
+test_disable '#!/bin/sh' tests/ls/stat-vs-dirent.sh
+test_disable '#!/bin/sh' tests/dd/sparse.sh
 test_disable 'int main(){return 0;}' gnulib-tests/test-chown.c
 test_disable 'int main(){return 0;}' gnulib-tests/test-fchownat.c
 test_disable 'int main(){return 0;}' gnulib-tests/test-lchown.c
@@ -440,7 +435,7 @@ package texinfo {
 
 	runtime = [
 		perl,
-		gawk,
+		awk,
 	];
 }
 
@@ -504,17 +499,14 @@ package parallel {
 	website = "https://www.gnu.org/software/parallel";
 	anitya = 5448;
 
-	version# = "20260522";
+	version# = "20260722";
 	source = remoteTar {
 		url = "https://ftpmirror.gnu.org/gnu/parallel/parallel-"+version+".tar.bz2";
-		checksum = "ezg3NZMlY-q-478YXmjWmDrDlaL55T7aBCuv3B7Z3DkAlfZRQEKO8eumqbcxTIy6";
+		checksum = "liG9pBSRqUPqDuRXmnJPoVh-G53lDKkkO8GGabSxQnSho4b9BD0EaJDdScgVhnwj";
 		compress = bzip2;
 	};
 
-	early = `
+	bin = [ "bash" ];
-ln -s ../system/bin/bash /bin/
-`;
-
 	exec = make {};
 
 	inputs = [

internal/rosa/package/gnutls/package.az

@@ -34,7 +34,8 @@ echo 'int main(){return 0;}' > tests/mini-dtls-fragments.c
 			"with-zstd": "link";
 
 			"": arch {
-				arm64 = "disable-hardware-acceleration";
+				// miscompilation on arm64
+				arm64 = "--disable-hardware-acceleration";
 			};
 		};
 	};

internal/rosa/package/go/746640.patch

@@ -0,0 +1,29 @@
+From 45929774c3d5c084cc478afba63c77cf67a68bd7 Mon Sep 17 00:00:00 2001
+From: khr@golang.org <khr@golang.org>
+Date: Wed, 18 Feb 2026 09:09:57 -0800
+Subject: [PATCH] internal/runtime/gc/scan: require popcnt for x86
+
+The GOAMD64=v1 test disables popcnt instructions, which is a feature
+this package's amd64 assembly uses.
+
+Fixes #77674
+
+Change-Id: I7be9bb665838f5da50275f96ef3df398412bb44a
+Reviewed-on: https://go-review.googlesource.com/c/go/+/746640
+LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
+Reviewed-by: Michael Knyszek <mknyszek@google.com>
+Reviewed-by: Keith Randall <khr@google.com>
+Auto-Submit: Keith Randall <khr@golang.org>
+---
+
+diff --git a/src/internal/runtime/gc/scan/scan_amd64.go b/src/internal/runtime/gc/scan/scan_amd64.go
+index c03021c7d4..544b237770 100644
+--- a/src/internal/runtime/gc/scan/scan_amd64.go
++++ b/src/internal/runtime/gc/scan/scan_amd64.go
+@@ -39,4 +39,5 @@ var avx512ScanPackedReqsMet = cpu.X86.HasAVX512VL &&
+ 	cpu.X86.HasGFNI &&
+ 	cpu.X86.HasAVX512BITALG &&
+ 	cpu.X86.HasAVX512DQ && // for kmovb, see #79871
+-	cpu.X86.HasAVX512VBMI
++	cpu.X86.HasAVX512VBMI &&
++	cpu.X86.HasPOPCNT

internal/rosa/package/go/799064.patch

@@ -0,0 +1,135 @@
+From 06f90ebfa6f3e0a744584513e2786988b26569da Mon Sep 17 00:00:00 2001
+From: Damien Neil <dneil@google.com>
+Date: Wed, 08 Jul 2026 11:11:48 -0700
+Subject: [PATCH] os: properly handle trailing / in Root.MkdirAll
+
+MkdirAll("dir/") should create "dir", not return an error.
+
+Fixes #80308
+
+Change-Id: I75458c30b6cb94be3a3d368f6024caef6a6a6964
+---
+
+diff --git a/src/os/root_noopenat.go b/src/os/root_noopenat.go
+index 228b580..a84e952 100644
+--- a/src/os/root_noopenat.go
++++ b/src/os/root_noopenat.go
+@@ -158,6 +158,9 @@
+ 	if err := checkPathEscapes(r, name); err == errPathEscapes {
+ 		return &PathError{Op: "mkdirat", Path: name, Err: err}
+ 	}
++	if name == "" {
++		return &PathError{Op: "mkdirat", Path: name, Err: syscall.ENOENT}
++	}
+ 	prefix := r.root.name + string(PathSeparator)
+ 	if err := MkdirAll(prefix+name, perm); err != nil {
+ 		if pe, ok := err.(*PathError); ok {
+diff --git a/src/os/root_openat.go b/src/os/root_openat.go
+index d7c9334..92865e4 100644
+--- a/src/os/root_openat.go
++++ b/src/os/root_openat.go
+@@ -167,6 +167,12 @@
+ 					fi, e := r.Stat(fullname)
+ 					if e == nil && fi.Mode().IsDir() {
+ 						err = nil
++					} else if e == nil {
++						err = syscall.ENOTDIR
++					} else if !IsNotExist(e) {
++						// EPERM, ELOOP, etc.,
++						// probably more useful than EEXIST.
++						err = e
+ 					}
+ 				}
+ 			}
+@@ -177,7 +183,12 @@
+ 		}
+ 		return struct{}{}, &PathError{Op: "mkdirat", Err: err}
+ 	}
+-	_, err := doInRoot(r, fullname, 0, openDirFunc, openLastComponentFunc)
++	flags := uint(doInRootCreatingDirectory)
++	switch runtime.GOOS {
++	case "linux", "windows":
++		flags = doInRootNoHandleTerminalSlash // see rootMkdir
++	}
++	_, err := doInRoot(r, fullname, flags, openDirFunc, openLastComponentFunc)
+ 	if err != nil {
+ 		if _, ok := err.(*PathError); !ok {
+ 			err = &PathError{Op: "mkdirat", Path: fullname, Err: err}
+diff --git a/src/os/root_test.go b/src/os/root_test.go
+index 5e0acf9..33a2f33 100644
+--- a/src/os/root_test.go
++++ b/src/os/root_test.go
+@@ -585,6 +585,11 @@
+ 
+ func TestRootMkdirAll(t *testing.T) {
+ 	for _, test := range rootTestCases {
++		if test.name == "directory does not exist" {
++			// Test expects error, mkdirall creates the missing directory.
++			// TestRootMultiMkdirAll covers this case better anyway, just skip.
++			continue
++		}
+ 		test.run(t, func(t *testing.T, target string, root *os.Root) {
+ 			wantError := test.wantError
+ 			if test.ltarget != "" {
+@@ -593,7 +598,7 @@
+ 				wantError = true
+ 			}
+ 
+-			err := root.Mkdir(test.open, 0o777)
++			err := root.MkdirAll(test.open, 0o777)
+ 			if errEndsTest(t, err, wantError, "root.MkdirAll(%q)", test.open) {
+ 				return
+ 			}
+@@ -3133,6 +3138,52 @@
+ 	})
+ }
+ 
++func TestRootMultiMkdirAllShallow(t *testing.T) {
++	runRootMultiTest(t, func(t *testing.T, test *rootMultiTest) (string, error) {
++		return testRootMultiMkdirAll(t, test, test.targetPath)
++	})
++}
++
++func TestRootMultiMkdirAllDeep(t *testing.T) {
++	runRootMultiTest(t, func(t *testing.T, test *rootMultiTest) (string, error) {
++		targetPath := test.targetPath
++		if len(targetPath) > 0 && os.IsPathSeparator(targetPath[len(targetPath)-1]) {
++			targetPath += "a/b/"
++		} else {
++			targetPath += "/a/b"
++		}
++		return testRootMultiMkdirAll(t, test, targetPath)
++	})
++}
++
++func testRootMultiMkdirAll(t *testing.T, test *rootMultiTest, targetPath string) (string, error) {
++	var mkdirAll = os.MkdirAll
++	if test.root != nil {
++		mkdirAll = test.root.MkdirAll
++	}
++
++	test.setOp("MkdirAll(%q, 0o777)", targetPath)
++	gotErr := mkdirAll(targetPath, 0o777)
++
++	switch {
++	case test.root != nil && test.target.lescapes():
++		// "mkdir ../target", or equivalent escaping path.
++		test.wantError(t, gotErr, os.ErrPathEscapes)
++	case test.root != nil && test.target.escapes():
++		// "mkdir ../target", or equivalent escaping path.
++		test.wantError(t, gotErr, errAny)
++		return "", errSkipRootConsistencyCheck
++	case test.root != nil && test.target.kind == testFileSymlink && test.target.target.kind == testFileAbsent && targetPath != test.targetPath:
++		// A minor inconsistency between Root.MkdirAll and os.MkdirAll:
++		// When an intermediate component of the tree being constructed is a
++		// dangling symlink, Root.MkdirAll will follow the symlink and create
++		// its target directory, while os.MkdirAll will fail with an error.
++		return "", errSkipRootConsistencyCheck
++	default:
++	}
++	return "", gotErr
++}
++
+ func TestRootMultiRename(t *testing.T) {
+ 	if runtime.GOOS == "wasip1" {
+ 		switch os.Getenv("GOWASIRUNTIME") {

internal/rosa/package/go/package.az

@@ -0,0 +1,64 @@
+package go {
+	description = "the Go programming language toolchain";
+	website = "https://go.dev";
+	anitya = 1227;
+
+	version# = "1.26.5";
+	source = remoteTar {
+		url = "https://go.dev/dl/go"+version+".src.tar.gz";
+		checksum = "13yt1u_NGOd62LO-WZ8W6CUXodOrEF5CdkiTTiH9E635IHn1luvlXYjsHpBXNFSw";
+		compress = gzip;
+	};
+
+	patches = [
+		// https://go.dev/issue/77674
+		"746640.patch",
+		// https://go.dev/issue/80308
+		"799064.patch",
+	];
+
+	env = [
+		"CC=cc",
+		"GOCACHE=/tmp/gocache",
+		"GOROOT_BOOTSTRAP=/system/go",
+		"TMPDIR=/dev/shm/go",
+	];
+
+	enterSource = true;
+
+	exec = generic {
+		inPlace = true;
+		build = `
+mkdir /work/system/ "${TMPDIR}"
+cp -r . /work/system/go
+cd /work/system/go/src/
+chmod -R +w ..
+
+sed -i \
+	's,/lib/ld-musl-`+linuxArch+`.so.1,/system/bin/linker,' \
+	cmd/link/internal/`+arch+`/obj.go
+
+rm \
+	os/root_unix_test.go \
+	runtime/crash_cgo_test.go \
+	cmd/cgo/internal/testsanitizers/tsan_test.go \
+	cmd/cgo/internal/testsanitizers/cshared_test.go
+
+set +u
+. ./make.bash "$@" --no-banner
+set -u
+`;
+		check = "bash run.bash --no-rebuild\n";
+		install = `
+../bin/go tool dist banner # print build info
+
+mkdir /work/system/bin
+ln -s \
+	../go/bin/go \
+	../go/bin/gofmt \
+	/work/system/bin
+`;
+	};
+
+	inputs = [ bash, go-bootstrap ];
+}

internal/rosa/package/hakurei/package.az

@@ -2,11 +2,11 @@ package hakurei-source {
 	description = "hakurei source tree";
 	exclude = true;
 
-	version# = "0.4.3";
+	version# = "0.4.5";
 	output = remoteTar {
 		url = "https://git.gensokyo.uk/rosa/hakurei/archive/"+
 			"v"+version+".tar.gz";
-		checksum = "1LqBJIcYcAFTVfydCahOm4hjjKhY953X9ars0eQj32hnpNncWFefuT6OJpZzIlZv";
+		checksum = "5bvbuIRcDIrtijogwqXn3y8h5f3rVS4ZSVhOig6Galfzt3g-O3Ufb-tHL1kQCQWK";
 		compress = gzip;
 	};
 }
@@ -48,8 +48,13 @@ go build -trimpath -tags=rosa -o /work/system/libexec/hakurei -ldflags="-s -w
 	-X hakurei.app/internal/info.buildVersion=$(cat cmd/dist/VERSION)
 	-X hakurei.app/internal/info.hakureiPath=/system/bin/hakurei
 	-X hakurei.app/internal/info.hsuPath=/system/bin/hsu
+" ./cmd/hakurei ./cmd/sharefs
+
+echo "Building hsu for $(go env GOOS)/$(go env GOARCH)."
+CGO_ENABLED=0 go build -trimpath -tags=rosa -o /work/system/libexec/hakurei -ldflags="-s -w
+	-buildid=
 	-X main.hakureiPath=/system/bin/hakurei
-" ./...
+" ./cmd/hsu
 echo`;
 		check = `
 echo '##### Testing hakurei.'

internal/rosa/package/harfbuzz.az

@@ -12,10 +12,10 @@ package harfbuzz {
 
 	exec = meson {
 		setup = {
-			"Dcairo": "enabled";
+			"cairo": "enabled";
-			"Dpng": "enabled";
+			"png": "enabled";
-			"Dzlib": "enabled";
+			"zlib": "enabled";
-			"Dfreetype": "enabled";
+			"freetype": "enabled";
 		};
 	};
 

internal/rosa/package/hwdata.az

@@ -3,11 +3,11 @@ package hwdata {
 	website = "https://github.com/vcrhonek/hwdata";
 	anitya = 5387;
 
-	version# = "0.408";
+	version# = "0.409";
 	source = remoteGitHub {
 		suffix = "vcrhonek/hwdata";
 		tag = "v"+version;
-		checksum = "1Rm52ovBb8sZRlA578EKgKSIea9QGgDVSBDETU872BisZTVosQy-OTKkWpzU_ddB";
+		checksum = "p2qr1_Y9dpjMNnK8OPNcuHSNwZldwb6mtiJ9Nd5HgU8z3L9fixLthnixywU8dd65";
 	};
 
 	writable = true;