diff --git a/.github/workflows/check-lock.yml b/.github/workflows/check-lock.yml
deleted file mode 100644
index 70d9e4ea..00000000
--- a/.github/workflows/check-lock.yml
+++ /dev/null
@@ -1,26 +0,0 @@
-name: Validate Flake Lock
-
-on:
-  workflow_dispatch:
-  push:
-    paths:
-      - "**.lock"
-
-permissions: {}
-
-jobs:
-  check-flake:
-    name: Check Lock
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
-        with:
-          persist-credentials: false
-
-      - name: Install Lix
-        uses: ./.github/actions/install-lix
-
-      - name: Check flake.lock
-        run: nix run github:extersia-org/pkgs#locker
diff --git a/modules/flake/programs/formatter.nix b/modules/flake/programs/formatter.nix
index e4389015..7ebf542b 100644
--- a/modules/flake/programs/formatter.nix
+++ b/modules/flake/programs/formatter.nix
@@ -1,18 +1,22 @@
 {
   lib,
+  writeShellScriptBin,
   treefmt,
+
+  # keep-sorted start
   actionlint,
   deadnix,
   keep-sorted,
+  locker,
   nixfmt,
   shellcheck,
   shfmt,
   statix,
+  stylua,
   taplo,
   yamlfmt,
   zizmor,
-  stylua,
-  writeShellScriptBin,
+  # keep-sorted end
 }:
 treefmt.withConfig {
   runtimeInputs = [
@@ -20,6 +24,7 @@ treefmt.withConfig {
     actionlint
     deadnix
     keep-sorted
+    locker
     nixfmt
     shellcheck
     shfmt
@@ -64,6 +69,11 @@ treefmt.withConfig {
         includes = [ "*" ];
       };
 
+      locker = {
+        command = "locker";
+        includes = [ "flake.lock" ];
+      };
+
       nixfmt = {
         command = "nixfmt";
         includes = [ "*.nix" ];