Pin nixpkgs

Author: sorki

default.nix

@@ -1,4 +1,11 @@
-{ pkgs ? import <nixpkgs> { overlays = [ (import ./overlay.nix) ]; }}:
+{ rev ? "c542baa0c894796c92a8173dead027f3b952c22e"
+, overlays ? [ (import ./overlay.nix) ]
+, pkgs ?
+    if ((rev == "") || (rev == "default") || (rev == "local"))
+      then import <nixpkgs> { inherit overlays; }
+      # Do not guard with hash, so the project is able to use current channels (rolling `rev`) of Nixpkgs
+      else import (builtins.fetchTarball "https://github.com/NixOS/nixpkgs/archive/${rev}.tar.gz") { inherit overlays; }
+}:
 
 let
   src = pkgs.nix-gitignore.gitignoreSource [ ] ./.;