do not run macos every time

.github/workflows/check.yml

@@ -1,5 +1,6 @@
 name: "Test template"
 on:
+  workflow_dispatch: # allows manual triggering
   pull_request:
   push:
 jobs:
@@ -7,11 +8,12 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-latest]
     steps:
     - uses: actions/checkout@v4
     - uses: cachix/install-nix-action@v31
       with:
         github_access_token: ${{ secrets.GITHUB_TOKEN }}
+    - uses: DeterminateSystems/magic-nix-cache-action@main
     - run: nix build ./templates/n
     - run: nix flake check ./templates/n

.github/workflows/check_macos.yml

@@ -0,0 +1,19 @@
+name: "Test template MacOS"
+on:
+  workflow_dispatch: # allows manual triggering
+  schedule:
+    - cron: '0 3 * * 0'
+jobs:
+  tests:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [macos-latest]
+    steps:
+    - uses: actions/checkout@v4
+    - uses: cachix/install-nix-action@v31
+      with:
+        github_access_token: ${{ secrets.GITHUB_TOKEN }}
+    - uses: DeterminateSystems/magic-nix-cache-action@main
+    - run: nix build ./templates/n
+    - run: nix flake check ./templates/n

.github/workflows/update.yml

@@ -3,7 +3,7 @@ name: update-flake-lock
 on:
   workflow_dispatch: # allows manual triggering
   schedule:
-    - cron: '0 0 0 * *'
+    - cron: '0 3 * * 0'
 
 jobs:
   lockfile:
@@ -13,6 +13,7 @@ jobs:
         uses: actions/checkout@v4
       - name: Install Determinate Nix
         uses: DeterminateSystems/determinate-nix-action@v3
+      - uses: DeterminateSystems/magic-nix-cache-action@main
       - name: Update n flake.lock
         uses: DeterminateSystems/update-flake-lock@v25
         with: