diff --git a/default.nix b/default.nix
index 945f76d..f85fc0c 100644
--- a/default.nix
+++ b/default.nix
@@ -1,9 +1,6 @@
-{
-  pkgs ? import (fetchTarball {
-    # nixos-unstable rev 2024-12-03
-    url = "https://github.com/NixOS/nixpkgs/archive/55d15ad12a74eb7d4646254e13638ad0c4128776.tar.gz";
-  }) { },
-}:
+{ pkgs ? import (fetchTarball {
+  url = "https://github.com/NixOS/nixpkgs/archive/refs/tags/24.05.tar.gz";
+}) {} }:
 
 let
   haskellPackages = pkgs.haskell.packages.ghc948;
diff --git a/rtlil-corpus b/rtlil-corpus
index d8f2b88..d60615b 160000
--- a/rtlil-corpus
+++ b/rtlil-corpus
@@ -1 +1 @@
-Subproject commit d8f2b884c523bdae74978fb52abe92d7487b1a9e
+Subproject commit d60615be78cd1fc7173bff956d2b1a53f8235bb0
diff --git a/shell.nix b/shell.nix
index ba4c573..ddb9d28 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,20 +1,12 @@
-{
-  pkgs ? import (fetchTarball {
-    # nixos-unstable rev 2024-12-03
-    url = "https://github.com/NixOS/nixpkgs/archive/55d15ad12a74eb7d4646254e13638ad0c4128776.tar.gz";
-  }) { },
-}:
+{ pkgs ? import (fetchTarball {
+  url = "https://github.com/NixOS/nixpkgs/archive/refs/tags/24.05.tar.gz";
+}) {} }:
 
 let
-  haskellator = pkgs.callPackage ./default.nix { };
-  corpus = pkgs.callPackage ./rtlil-corpus/default.nix { };
+  haskellator = pkgs.callPackage ./default.nix {};
 in
-pkgs.callPackage (
-  { mkShell }:
-  mkShell {
-    CORPUS = corpus;
-    nativeBuildInputs = [
-      haskellator
+pkgs.mkShell {
+  buildInputs = [
+    haskellator
     ];
-  }
-) { }
+}
diff --git a/test.py b/test.py
index 0dd7505..d7f89a4 100644
--- a/test.py
+++ b/test.py
@@ -1,30 +1,13 @@
 import os
 import subprocess
-import argparse
-import shutil
-
-parser = argparse.ArgumentParser(description="Test rtlil-parse")
-parser.add_argument("--corpus", default=os.environ.get('CORPUS'), required=False, help="Path to corpus dir.")
-args = parser.parse_args()
 
 # Define the directories
-if args.corpus:
-    corpus_dir = args.corpus
-else:
-    corpus_dir = './rtlil-corpus/corpus/'
-
+corpus_dir = './rtlil-corpus/corpus/'
 parsed_dir = './parsed_rtlil'
 
 # Create the parsed_rtlil directory if it doesn't exist
 os.makedirs(parsed_dir, exist_ok=True)
 
-# Use rtlil-parse from PATH if available.
-rtil_parse_binary = shutil.which("rtlil-parse")
-if rtil_parse_binary is None:
-    program = "cabal run rtlil-parse --"
-else:
-    program = rtil_parse_binary
-
 # Iterate over all .rtlil files in the corpus directory
 for file_name in os.listdir(corpus_dir):
     if file_name.endswith('.il'):
@@ -33,7 +16,7 @@ for file_name in os.listdir(corpus_dir):
         output_path = os.path.join(parsed_dir, output_file)
 
         # Construct and run the command
-        command = f"{program} {input_path} {output_path}"
+        command = f"cabal run rtlil-parse -- {input_path} {output_path}"
         try:
             subprocess.run(command, shell=True, check=True)
             print(f"Processed: {input_path} -> {output_path}")