diff --git a/internal/pipeline/build.go b/internal/pipeline/build.go
index 90a14ab..206e308 100644
--- a/internal/pipeline/build.go
+++ b/internal/pipeline/build.go
@@ -180,7 +180,7 @@ func planHAKs(p *project.Project, progress ProgressFunc) (BuildResult, error) {
 	return planOrBuildHAKs(p, progress, false, nil, "")
 }
 
-func planOrBuildHAKs(p *project.Project, progress ProgressFunc, writeArchives bool, archiveNames []string, sourceManifestPath string) (BuildResult, error) {
+func planOrBuildHAKs(p *project.Project, progress ProgressFunc, writeArchives bool, archiveNames []string, sourceManifestPath string) (result BuildResult, err error) {
 	preserveExistingHAKs := envBool("SOW_BUILD_HAKS_KEEP_EXISTING")
 
 	progressf(progress, "Validating project...")
@@ -197,6 +197,11 @@ func planOrBuildHAKs(p *project.Project, progress ProgressFunc, writeArchives bo
 	if err != nil {
 		return BuildResult{}, err
 	}
+	defer func() {
+		if cleanupErr := cleanupPreparedMusicAssets(musicAssets); cleanupErr != nil && err == nil {
+			err = cleanupErr
+		}
+	}()
 	assetResources, err := collectAssetResources(p, false, allowedAssets, musicAssets)
 	if err != nil {
 		return BuildResult{}, err
@@ -213,7 +218,7 @@ func planOrBuildHAKs(p *project.Project, progress ProgressFunc, writeArchives bo
 		}
 	}
 
-	result := BuildResult{HAKAssets: len(assetResources)}
+	result = BuildResult{HAKAssets: len(assetResources)}
 	result.CreditsArtifactPaths = append(result.CreditsArtifactPaths, musicAssets.Artifacts...)
 	if err := writeAutogenManifestOutputs(progress, autogenManifests); err != nil {
 		return BuildResult{}, err
@@ -1584,7 +1589,7 @@ func cleanupGeneratedHAKs(p *project.Project) error {
 	return nil
 }
 
-func plannedModuleHAKOrder(p *project.Project) ([]string, error) {
+func plannedModuleHAKOrder(p *project.Project) (order []string, err error) {
 	manifest, err := loadPreviousBuildManifest(p.HAKManifestPath())
 	if err != nil {
 		return nil, err
@@ -1597,6 +1602,11 @@ func plannedModuleHAKOrder(p *project.Project) ([]string, error) {
 	if err != nil {
 		return nil, err
 	}
+	defer func() {
+		if cleanupErr := cleanupPreparedMusicAssets(musicAssets); cleanupErr != nil && err == nil {
+			err = cleanupErr
+		}
+	}()
 	assetResources, err := collectAssetResources(p, false, nil, musicAssets)
 	if err != nil {
 		return nil, err
diff --git a/internal/pipeline/music.go b/internal/pipeline/music.go
index ef60f97..f047832 100644
--- a/internal/pipeline/music.go
+++ b/internal/pipeline/music.go
@@ -48,6 +48,7 @@ type preparedMusicAssets struct {
 	Generated     []assetResource
 	SkipSourceRel map[string]struct{}
 	Artifacts     []string
+	TempRoots     []string
 }
 
 type musicMetadata struct {
@@ -125,7 +126,8 @@ func prepareMusicAssets(p *project.Project) (*preparedMusicAssets, error) {
 	sort.Strings(dirs)
 
 	generatedByDir := make(map[string][]creditsEntry)
-	stageRoot := filepath.Join(p.BuildDir(), ".cache", "music")
+	stageRoot := filepath.Join(p.Root, ".cache", "music")
+	result.TempRoots = append(result.TempRoots, stageRoot)
 
 	ffmpegPath, err := resolveFFmpegBinary()
 	if err != nil {
@@ -227,7 +229,10 @@ func prepareMusicAssets(p *project.Project) (*preparedMusicAssets, error) {
 }
 
 func writeCreditsArtifacts(p *project.Project, generatedByDir map[string][]creditsEntry) ([]string, error) {
-	creditsRoot := filepath.Join(p.BuildDir(), "credits")
+	creditsRoot := filepath.Join(p.Root, ".cache", "credits")
+	if err := os.RemoveAll(creditsRoot); err != nil {
+		return nil, fmt.Errorf("reset credits dir: %w", err)
+	}
 	if err := os.MkdirAll(creditsRoot, 0o755); err != nil {
 		return nil, fmt.Errorf("create credits dir: %w", err)
 	}
@@ -310,6 +315,21 @@ func writeCreditsArtifacts(p *project.Project, generatedByDir map[string][]credi
 	return artifacts, nil
 }
 
+func cleanupPreparedMusicAssets(prepared *preparedMusicAssets) error {
+	if prepared == nil {
+		return nil
+	}
+	for _, root := range prepared.TempRoots {
+		if strings.TrimSpace(root) == "" {
+			continue
+		}
+		if err := os.RemoveAll(root); err != nil {
+			return fmt.Errorf("remove temporary music artifact root %s: %w", root, err)
+		}
+	}
+	return nil
+}
+
 func parseCreditsOverlay(path string) (creditsOverlay, error) {
 	entries, err := parseCreditsMarkdown(path)
 	if err != nil {
diff --git a/internal/pipeline/pipeline_test.go b/internal/pipeline/pipeline_test.go
index 915fcb2..094062c 100644
--- a/internal/pipeline/pipeline_test.go
+++ b/internal/pipeline/pipeline_test.go
@@ -2659,7 +2659,7 @@ func TestBuildHAKsConvertsMusicSourcesAndWritesCreditsArtifacts(t *testing.T) {
 		t.Fatalf("did not expect source mp3 in manifest, got %s", string(manifestRaw))
 	}
 
-	creditsRaw, err := os.ReadFile(filepath.Join(root, "build", "credits", "envi", "music", "westgate", "CREDITS.md"))
+	creditsRaw, err := os.ReadFile(filepath.Join(root, ".cache", "credits", "envi", "music", "westgate", "CREDITS.md"))
 	if err != nil {
 		t.Fatalf("read generated credits: %v", err)
 	}
@@ -2671,7 +2671,7 @@ func TestBuildHAKsConvertsMusicSourcesAndWritesCreditsArtifacts(t *testing.T) {
 		t.Fatalf("manual credits overlay should override bad metadata: %s", creditsText)
 	}
 
-	inventoryRaw, err := os.ReadFile(filepath.Join(root, "build", "credits", "credits.json"))
+	inventoryRaw, err := os.ReadFile(filepath.Join(root, ".cache", "credits", "credits.json"))
 	if err != nil {
 		t.Fatalf("read credits inventory: %v", err)
 	}
@@ -2679,7 +2679,10 @@ func TestBuildHAKsConvertsMusicSourcesAndWritesCreditsArtifacts(t *testing.T) {
 	if !strings.Contains(inventoryText, "assets/envi/music/westgate/CREDITS.md") {
 		t.Fatalf("expected authored credits source in inventory: %s", inventoryText)
 	}
-	if !strings.Contains(inventoryText, "build/credits/envi/music/westgate/CREDITS.md") {
+	if !strings.Contains(inventoryText, ".cache/credits/envi/music/westgate/CREDITS.md") {
 		t.Fatalf("expected generated credits source in inventory: %s", inventoryText)
 	}
+	if _, err := os.Stat(filepath.Join(root, ".cache", "music")); !os.IsNotExist(err) {
+		t.Fatalf("expected temporary music staging to be cleaned, got err=%v", err)
+	}
 }