add lib/overlays.nix

1 files changed, 13 insertions, 0 deletions

diff --git a/lib/overlays.nix b/lib/overlays.nix
new file mode 100644
index 0000000..7779e13
--- /dev/null
+++ b/lib/overlays.nix
@@ -0,0 +1,13 @@
+{ config, lib, pkgs, ... }:
+{
+  options = {
+    overlays = lib.mkOption {
+      type = lib.types.listOf (lib.types.functionTo (lib.types.functionTo (lib.types.lazyAttrsOf lib.types.unspecified)));
+      default = [];
+    };
+    outputs.overlay = lib.mkOption {
+      type = lib.types.functionTo (lib.types.functionTo (lib.types.lazyAttrsOf lib.types.unspecified));
+    };
+  };
+  config.outputs.overlay = lib.composeManyExtensions config.overlays;
+}