Exercise Nix build in workflow (#46)

.github/workflows/dotnet.yaml

@@ -38,14 +38,14 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
-      - name: Setup .NET
-        uses: actions/setup-dotnet@v3
-        with:
-          dotnet-version: 7.0.x
+      - name: Install Nix
+        uses: cachix/install-nix-action@v17
+      - name: Build
+        run: nix build
       - name: Run app
-        run: dotnet run --project AdventOfCode2022.App/AdventOfCode2022.App.fsproj --configuration Release
+        run: ./result/bin/AdventOfCode2022.App
 
-  check-format:
+  check-dotnet-format:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
@@ -59,13 +59,26 @@ jobs:
       - name: Run Fantomas
         run: ./hooks/pre-push
 
+  check-nix-format:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - uses: actions/checkout@v3
+      - name: Install Nix
+        uses: cachix/install-nix-action@v17
+      - name: Run Alejandra
+        run: nix develop --command alejandra --check .
+
   shellcheck:
     name: Shellcheck
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
+      - name: Install Nix
+        uses: cachix/install-nix-action@v17
       - name: Run ShellCheck
-        uses: ludeeus/action-shellcheck@master
+        run: nix shell 'nixpkgs#shellcheck' --command bash -c "find . -type f -name '*.sh' | xargs shellcheck"
 
   linkcheck:
     name: Check links
@@ -76,7 +89,7 @@ jobs:
         name: Run link checker
 
   all-required-checks-complete:
-    needs: [check-format, build, shellcheck, linkcheck, run-app]
+    needs: [check-dotnet-format, check-nix-format, build, shellcheck, linkcheck, run-app]
     runs-on: ubuntu-latest
     steps:
       - run: echo "All required checks complete."