diff --git a/nix/sources.json b/nix/sources.json
index f900cdd..d73c3d0 100644
--- a/nix/sources.json
+++ b/nix/sources.json
@@ -36,15 +36,15 @@
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "nixos-unstable": {
-        "branch": "master",
+        "branch": "lib-modules-allow-disable-_modules.args-docs-internal",
         "description": "A read-only mirror of NixOS/nixpkgs tracking the released channels. Send issues and PRs to",
         "homepage": "https://github.com/NixOS/nixpkgs",
-        "owner": "NixOS",
+        "owner": "hercules-ci",
         "repo": "nixpkgs",
-        "rev": "55e580b86dd4402fbc2a6793bba6dcf40c56652c",
-        "sha256": "0jnn3ilwxycmqpgjc50g9qcl4z52jnjs70zirxl8cgk3yip3skmw",
+        "rev": "35f40b20607428901e8edace7d4643d4ac11e876",
+        "sha256": "0w1ivhzszggq2j4fxbhdppvzj07zkginfnqdpkl6mdzvpwhy8f0d",
         "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/55e580b86dd4402fbc2a6793bba6dcf40c56652c.tar.gz",
+        "url": "https://github.com/hercules-ci/nixpkgs/archive/35f40b20607428901e8edace7d4643d4ac11e876.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz",
         "version": ""
     },
diff --git a/src/nix/modules/composition/composition.nix b/src/nix/modules/composition/composition.nix
index fa46617..37d2854 100644
--- a/src/nix/modules/composition/composition.nix
+++ b/src/nix/modules/composition/composition.nix
@@ -8,6 +8,9 @@ let
 in
 {
   options = {
+    _module.args = mkOption {
+      internal = true;
+    };
     project.name = mkOption {
       description = ''
         Name of the project.