diff --git a/nixos/release-combined.nix b/nixos/release-combined.nix
index d4f77ea445d061..9d4a551a958b80 100644
--- a/nixos/release-combined.nix
+++ b/nixos/release-combined.nix
@@ -2,7 +2,7 @@
 # and nixos-14.04). The channel is updated every time the ‘tested’ job
 # succeeds, and all other jobs have finished (they may fail).
 
-{ nixpkgs ? { outPath = ./..; revCount = 56789; shortRev = "gfedcba"; }
+{ nixpkgs ? { outPath = (import ../lib).cleanSource ./..; revCount = 56789; shortRev = "gfedcba"; }
 , stableBranch ? false
 , supportedSystems ? [ "x86_64-linux" ]
 , limitedSupportedSystems ? [ "i686-linux" ]
diff --git a/nixos/release-small.nix b/nixos/release-small.nix
index e9f3cfb4de5396..24c448449c1fab 100644
--- a/nixos/release-small.nix
+++ b/nixos/release-small.nix
@@ -2,7 +2,7 @@
 # small subset of Nixpkgs, mostly useful for servers that need fast
 # security updates.
 
-{ nixpkgs ? { outPath = ./..; revCount = 56789; shortRev = "gfedcba"; }
+{ nixpkgs ? { outPath = (import ../lib).cleanSource ./..; revCount = 56789; shortRev = "gfedcba"; }
 , stableBranch ? false
 , supportedSystems ? [ "x86_64-linux" ] # no i686-linux
 }:
diff --git a/nixos/release.nix b/nixos/release.nix
index e9d145031c4fa7..2c6055003767ad 100644
--- a/nixos/release.nix
+++ b/nixos/release.nix
@@ -1,4 +1,4 @@
-{ nixpkgs ? { outPath = ./..; revCount = 56789; shortRev = "gfedcba"; }
+{ nixpkgs ? { outPath = (import ../lib).cleanSource ./..; revCount = 56789; shortRev = "gfedcba"; }
 , stableBranch ? false
 , supportedSystems ? [ "x86_64-linux" "aarch64-linux" ]
 }: