diff --git a/nix/sources.json b/nix/sources.json
index f7fe3035..b6c45410 100644
--- a/nix/sources.json
+++ b/nix/sources.json
@@ -35,12 +35,6 @@
         "rev": "312a8bc1fd1ed04c6564be4db4d08b7bcdc64764",
         "type": "git"
     },
-    "nix-output-monitor": {
-        "branch": "master",
-        "repo": "git@hera.m-0.eu:nix-output-monitor",
-        "rev": "5bf7534a9992d5b3f08b16b1a389d869f6f4c835",
-        "type": "git"
-    },
     "nixos-20.09": {
         "branch": "nixos-20.09",
         "description": "Nixpkgs/NixOS branches that track the Nixpkgs/NixOS channels",
diff --git a/overlays/30-ghc.nix b/overlays/30-ghc.nix
index 23183808..da58271c 100644
--- a/overlays/30-ghc.nix
+++ b/overlays/30-ghc.nix
@@ -19,6 +19,7 @@ let
         hspec-discover cabal-edit paths;
     } // makeHaskellScriptPackages p;
 in {
+  nix-output-monitor = master.nix-output-monitor;
   myHaskellPackages = makeHaskellPackages master.haskellPackages;
   scriptGhc = master.ghc.withPackages
     (p: builtins.attrValues (makeHaskellScriptPackages p));
diff --git a/overlays/nix-output-monitor/default.nix b/overlays/nix-output-monitor/default.nix
deleted file mode 100644
index 7ea689f1..00000000
--- a/overlays/nix-output-monitor/default.nix
+++ /dev/null
@@ -1,5 +0,0 @@
-final: prev:
-let master = import prev.sources.nixpkgs-master { };
-in {
-  nix-output-monitor = import prev.sources.nix-output-monitor { pkgs = final; };
-}