diff --git a/internal/pkg/compress_test.go b/internal/pkg/compress_test.go
index 3b9516d4..7ce00edf 100644
--- a/internal/pkg/compress_test.go
+++ b/internal/pkg/compress_test.go
@@ -36,6 +36,12 @@ func TestDecompress(t *testing.T) {
 		return (pkg.Checksum)(h.Sum(nil))
 	}()
 
+	gh := pkg.NewDecompress(pkg.NewHTTPGet(
+		&client,
+		"file:///testdata",
+		testdataChecksum,
+	), pkg.Gzip)
+
 	checkWithCache(t, []cacheTestCase{
 		{"decompress", 0, nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
 			cureMany(t, c, []cureStep{
@@ -48,11 +54,7 @@ func TestDecompress(t *testing.T) {
 					Want: pkg.Checksum{0xfd},
 				}},
 
-				{"gzip", pkg.NewDecompress(pkg.NewHTTPGet(
-					&client,
-					"file:///testdata",
-					testdataChecksum,
-				), pkg.Gzip), ignorePathname, expectsChecksum(sha512.Sum384([]byte{0})), pkg.WNew, nil},
+				{"gzip", gh, ignorePathname, expectsChecksum(sha512.Sum384([]byte{0})), pkg.WNew, nil},
 			})
 		}, expectsFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -61,7 +63,7 @@ func TestDecompress(t *testing.T) {
 			"checksum/" + pkg.Encode(sha512.Sum384([]byte{0})): {Mode: 0400, Data: []byte{0}},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/mae-iR_9LFT_BOEJ2IRzKsAlI754SalMjjt95fZeMd3gEyAzsrvuOXnXN0bFZJi4": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX")},
+			"identifier/" + pkg.Encode(pkg.NewIR().Ident(gh).Value()): {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX")},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 			"work":       {Mode: fs.ModeDir | 0700},
diff --git a/internal/pkg/tar_test.go b/internal/pkg/tar_test.go
index f4a4286b..1f280e9c 100644
--- a/internal/pkg/tar_test.go
+++ b/internal/pkg/tar_test.go
@@ -3,7 +3,6 @@ package pkg_test
 import (
 	"archive/tar"
 	"bytes"
-	"compress/gzip"
 	"crypto/sha512"
 	"errors"
 	"io/fs"
@@ -80,8 +79,8 @@ func TestTar(t *testing.T) {
 			"checksum/" + wantEncode + "/work": {Mode: fs.ModeDir | 0500},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/7OZ5ErCxUJyRnaaFvUKhTryjsJAoOBUR2MZpUB1DD57jRa09Xxsh9BUs0dM9z5uH": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantEncode)},
-			"identifier/paWdPW_BowV3345c4GP4xxSNgxVs_7F09m9m7OaH5XbyuI3dTGZ-kFPOXFbwgr5O": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantEncode)},
+			"identifier/snWp53xxNdx6cV5KSJqzyVWzLlTsFd8udOisIu8Rgxly09mGcxufYCoQ5CQrHDyZ": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantEncode)},
+			"identifier/v9DUj2R4YK_3ae0m9VuUYI-HJysDDCENu1k10thxioycRzFH1Qejw5bBGukm4IdL": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantEncode)},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 
@@ -104,8 +103,8 @@ 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/1g2Tcg7pOJkZFxlKploBm4U0vIyMYbxDkcwwydwsF9BMs-w-knFJS41jnqOt16jT": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantExpandEncode)},
-			"identifier/7OZ5ErCxUJyRnaaFvUKhTryjsJAoOBUR2MZpUB1DD57jRa09Xxsh9BUs0dM9z5uH": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantExpandEncode)},
+			"identifier/1SuvgGltcsgqps9tWqjULG8RCdpx_6KVWXdsMd5xPKvdtysOxqpE-3bLu4j0WpGk": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantExpandEncode)},
+			"identifier/snWp53xxNdx6cV5KSJqzyVWzLlTsFd8udOisIu8Rgxly09mGcxufYCoQ5CQrHDyZ": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/" + wantExpandEncode)},
 
 			"substitute": {Mode: fs.ModeDir | 0700},
 
@@ -132,16 +131,7 @@ func checkTarHTTP(
 		if err := w.Close(); err != nil {
 			t.Fatalf("Close: error = %v", err)
 		}
-
-		var zbuf bytes.Buffer
-		gw := gzip.NewWriter(&zbuf)
-		if _, err := gw.Write(buf.Bytes()); err != nil {
-			t.Fatalf("Write: error = %v", err)
-		}
-		if err := gw.Close(); err != nil {
-			t.Fatalf("Close: error = %v", err)
-		}
-		testdata = zbuf.String()
+		testdata = buf.String()
 	}
 
 	testdataChecksum := func() pkg.Checksum {
@@ -208,28 +198,19 @@ func checkTarHTTP(
 	defer newDestroyArtifactFunc(&tarDirType)(t, base, c)
 
 	cureMany(t, c, []cureStep{
-		{"file", pkg.NewTar(pkg.NewDecompress(pkg.NewHTTPGet(
+		{"file", pkg.NewTar(pkg.NewHTTPGet(
 			&client,
 			"file:///testdata",
 			testdataChecksum,
-		), pkg.Gzip)), ignorePathname, want, pkg.WNew, nil},
-
-		{"directory", pkg.NewTar(pkg.NewDecompress(
-			&tarDir,
-			pkg.Gzip,
 		)), ignorePathname, want, pkg.WNew, nil},
 
-		{"multiple entries", pkg.NewTar(pkg.NewDecompress(
-			&tarDirMulti,
-			pkg.Gzip,
-		)), nil, nil, pkg.WNew, errors.New(
+		{"directory", pkg.NewTar(&tarDir), ignorePathname, want, pkg.WNew, nil},
+
+		{"multiple entries", pkg.NewTar(&tarDirMulti), 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, pkg.WNew, errors.New(
+		{"bad type", pkg.NewTar(&tarDirType), nil, nil, pkg.WNew, errors.New(
 			"input directory does not contain a single regular file",
 		)},