diff --git a/internal/rosa/cmake.go b/internal/rosa/cmake.go
index 1226f5ae..802a0b30 100644
--- a/internal/rosa/cmake.go
+++ b/internal/rosa/cmake.go
@@ -127,6 +127,11 @@ type CMakeHelper struct {
 	// Runs after install.
 	Script string
 
+	// Replaces the default test command.
+	Test string
+	// Whether to skip running tests.
+	SkipTest bool
+
 	// Whether to generate Makefile instead.
 	Make bool
 }
@@ -170,8 +175,18 @@ func (attr *CMakeHelper) script(name string) string {
 	}
 
 	generate := "Ninja"
+	test := "ninja " + jobsFlagE + " test"
 	if attr.Make {
 		generate = "'Unix Makefiles'"
+		test = "make " + jobsFlagE + " test"
+	}
+	if attr.Test != "" {
+		test = attr.Test
+	}
+
+	script := attr.Script
+	if !attr.SkipTest {
+		script += "\n" + test
 	}
 
 	return `
@@ -191,5 +206,5 @@ cmake -G ` + generate + ` \
 	'/usr/src/` + name + `/` + filepath.Join(attr.Append...) + `'
 cmake --build . --parallel=` + jobsE + `
 cmake --install . --prefix=/work/system
-` + attr.Script
+` + script
 }
diff --git a/internal/rosa/glslang.go b/internal/rosa/glslang.go
index f05a1a62..a2600ea3 100644
--- a/internal/rosa/glslang.go
+++ b/internal/rosa/glslang.go
@@ -20,6 +20,9 @@ func (t Toolchain) newSPIRVHeaders() (pkg.Artifact, string) {
 		Cache: []KV{
 			{"CMAKE_BUILD_TYPE", "Release"},
 		},
+
+		// upstream has no tests
+		SkipTest: true,
 	}), version
 }
 func init() {
@@ -110,7 +113,6 @@ func (t Toolchain) newGlslang() (pkg.Artifact, string) {
 			{"BUILD_SHARED_LIBS", "ON"},
 			{"ALLOW_EXTERNAL_SPIRV_TOOLS", "ON"},
 		},
-		Script: "ctest",
 	},
 		Python,
 		Bash,
diff --git a/internal/rosa/zlib.go b/internal/rosa/zlib.go
index ab1ae7ea..4f6591b0 100644
--- a/internal/rosa/zlib.go
+++ b/internal/rosa/zlib.go
@@ -16,7 +16,7 @@ func (t Toolchain) newZlib() (pkg.Artifact, string) {
 			{"CMAKE_BUILD_TYPE", "Release"},
 
 			{"CMAKE_C_FLAGS", "-fPIC"},
-			{"ZLIB_BUILD_TESTING", "OFF"},
+			{"ZLIB_BUILD_TESTING", "ON"},
 			{"ZLIB_BUILD_SHARED", "ON"},
 			{"ZLIB_BUILD_STATIC", "ON"},
 			{"ZLIB_BUILD_MINIZIP", "OFF"},
diff --git a/internal/rosa/zstd.go b/internal/rosa/zstd.go
index 0a3043df..52a74e35 100644
--- a/internal/rosa/zstd.go
+++ b/internal/rosa/zstd.go
@@ -13,12 +13,23 @@ func (t Toolchain) newZstd() (pkg.Artifact, string) {
 		"zstd-"+version+".tar.gz",
 		checksum,
 		pkg.TarGzip,
-	), nil, &CMakeHelper{
+	), &PackageAttr{
+		// tests Makefile assumes writable source
+		Writable: true,
+		Chmod:    true,
+	}, &CMakeHelper{
 		Append: []string{"build", "cmake"},
 		Cache: []KV{
 			{"CMAKE_BUILD_TYPE", "Release"},
 		},
-	}), version
+		Test: `
+make -C /usr/src/zstd/tests datagen
+ZSTD_BIN=/cure/programs/zstd /usr/src/zstd/tests/playTests.sh
+`,
+	},
+		Make,
+		Diffutils,
+	), version
 }
 func init() {
 	artifactsM[Zstd] = Metadata{