diff --git a/dockerimg/dockerimg.go b/dockerimg/dockerimg.go
index 6164a31..0a070cf 100644
--- a/dockerimg/dockerimg.go
+++ b/dockerimg/dockerimg.go
@@ -662,7 +662,7 @@
 		if err != nil {
 			return "", fmt.Errorf("create dockerfile: %w", err)
 		}
-		dockerfilePath = filepath.Join(cwd, "tmp-sketch-dockerfile")
+		dockerfilePath = filepath.Join(cwd, tmpSketchDockerfile)
 		if err := os.WriteFile(dockerfilePath, []byte(dockerfile), 0o666); err != nil {
 			return "", err
 		}