diff --git a/flake.nix b/flake.nix
index eac499d..e614aaa 100644
--- a/flake.nix
+++ b/flake.nix
@@ -8,7 +8,7 @@
      let system = "x86_64-linux"; in
      let nixpkgs = import nixpkgs-git { config = { allowUnfree = true;}; system = system; }; in
 
-     let mypackages = with nixpkgs; [ coreutils python3 sqlite gawk git file bash bashInteractive gnutar gzip ]; in
+     let mypackages = with nixpkgs; [ coreutils python3 sqlite gawk git file bash bashInteractive gnutar gzip gnugrep gnused ]; in
 
      with import nixpkgs-git { system = "x86_64-linux"; };
      symlinkJoin {
diff --git a/hash-files.py b/hash-files.py
index c120642..5284741 100755
--- a/hash-files.py
+++ b/hash-files.py
@@ -5,7 +5,8 @@ import sys
 import subprocess
 
 def debug(s):
-  print(s, file=sys.stderr, flush=True)
+  #print(s, file=sys.stderr, flush=True)
+  pass
 
 
 def hashFile(filename):
diff --git a/test.py b/test.py
index f48e3cb..5bb3417 100755
--- a/test.py
+++ b/test.py
@@ -59,11 +59,9 @@ with tempfile.TemporaryDirectory(prefix="test", dir="/tmp") as tempdir:
     h = subprocess.check_output([os.path.abspath('./hash-files.py'), 'test/foo'], cwd=tempdir).strip()
     if h == b'f31eb7e1bcb25e79be0d1305d58eeadbe3fd9bf38ecbd0449789e8c91b5f4340':
         print("test passed: git\n", flush=True)
-        subprocess.check_output("tar -zcf /tmp/debug-git.tar.gz .", cwd=tempdir, shell=True)
     else:
         print("TEST FAILED: git: got hash " + repr(h) + "\n", flush=True)
-        subprocess.check_output("tar -zcf /tmp/debug-git.tar.gz .", cwd=tempdir, shell=True)
-        exit(0)
+        exit(1)
 
 # Sqlite
 with tempfile.TemporaryDirectory(prefix="test", dir="/tmp") as tempdir:
@@ -96,11 +94,9 @@ with tempfile.TemporaryDirectory(prefix="test", dir="/tmp") as tempdir:
     h = subprocess.check_output([os.path.abspath('./hash-files.py'), 'test/foo'], cwd=tempdir).strip()
     if h == b'b775b5c3ad1b403c08fa88e43be42bd76143f93c26bf42cb8881c595161a5509':
         print("test passed: sqlite\n", flush=True)
-        subprocess.check_output("tar -zcf /tmp/debug-sql.tar.gz .", cwd=tempdir, shell=True)
     else:
         print("TEST FAILED: sqlite got hash " + repr(h) + "\n", flush=True)
-        subprocess.check_output("tar -zcf /tmp/debug-sql.tar.gz .", cwd=tempdir, shell=True)
-        exit(0)
+        exit(1)
 
 # Sqlite big table
 with tempfile.TemporaryDirectory(prefix="test", dir="/tmp") as tempdir: