feat: use Nix flake for lint and test flows

Author: ar3s3ru

.github/actions/go-setup/action.yaml

@@ -0,0 +1,16 @@
+---
+name: Setup Go
+description: |
+  Sets up the Go toolchain cache for faster execution.
+runs:
+  using: composite
+  steps:
+    - name: Setup cache
+      uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4
+      with:
+        path: |
+          ~/.cache/go-build
+          ~/go/pkg/mod
+        key: ${{ runner.os }}-${{ github.workflow }}-golang-${{ hashFiles('**/go.sum') }}
+        restore-keys: |
+          ${{ runner.os }}-${{ github.workflow }}-golang-

.github/actions/golangci-lint-setup/action.yaml

@@ -0,0 +1,20 @@
+---
+name: Setup golangci-lint
+description: |
+  Sets up golangci-lint cache and smooth buttery experience to make it go brrrr!
+runs:
+  using: composite
+  steps:
+    - name: Setup Go
+      uses: ./.github/actions/go-setup
+    - name: Set cache directory in env
+      shell: bash
+      run: |
+        echo "GOLANGCI_LINT_CACHE=$HOME/.cache/golangci-lint" >> $GITHUB_ENV
+    - name: Setup cache
+      uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4
+      with:
+        path: ${{ env.GOLANGCI_LINT_CACHE }}
+        key: ${{ runner.os }}-golangci-lint-cache-${{ hashFiles('**/go.sum') }}
+        restore-keys: |
+          ${{ runner.os }}-golangci-lint-cache-

.github/actions/nix-setup/action.yaml

@@ -0,0 +1,19 @@
+---
+name: Setup Nix and direnv
+description: |
+  Sets up the Nix package manager and direnv to use the same packages
+  vendored through Nix for local development.
+inputs:
+  github_token:
+    description: 'Github Access Token'
+    required: true
+runs:
+  using: composite
+  steps:
+    - name: Install Nix package manager
+      uses: DeterminateSystems/nix-installer-action@e50d5f73bfe71c2dd0aa4218de8f4afa59f8f81d # v16
+      with:
+        extra-conf: |
+          experimental-features = nix-command flakes
+    - name: Set up Nix cache
+      uses: DeterminateSystems/magic-nix-cache-action@6221693898146dc97e38ad0e013488a16477a4c4 # v9

.github/workflows/lint.yml

@@ -24,15 +24,20 @@ jobs:
       pull-requests: write
     steps:
       - name: Checkout source code
-        uses: actions/checkout@v4
-      - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
         with:
-          go-version: '1.21'
-      - name: Run golangci-lint
-        uses: golangci/golangci-lint-action@v6
+          fetch-depth: 0
+      - name: Set up Nix system
+        uses: ./.github/actions/nix-setup
         with:
-          args: --timeout=5m
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Setup Go
+        uses: ./.github/actions/go-setup # NOTE: used for caching only.
+      - name: Set up golangci-lint
+        uses: ./.github/actions/golangci-lint-setup
+      - name: Run golangci-lint
+        run: make go.lint
+        shell: nix develop --quiet -c bash -e {0}
 
   super-linter:
     name: Super Linter

.github/workflows/test.yml

@@ -21,13 +21,16 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout source code
-        uses: actions/checkout@v4
-      - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+      - name: Set up Nix system
+        uses: ./.github/actions/nix-setup
         with:
-          go-version: '1.21'
-      - name: Run go test
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Setup Go
+        uses: ./.github/actions/go-setup # NOTE: used for caching only.
+      - name: Run 'make go.test'
         run: make go.test
+        shell: nix develop --quiet -c bash -e {0}
       - name: Upload coverage report
         uses: codecov/codecov-action@v4
         with:

.golangci.yaml

@@ -2,7 +2,7 @@
 version: "2"
 
 run:
-  go: "1.23"
+  timeout: 5m
 
 linters:
   default: none

internal/user/user_by_email.go

@@ -78,9 +78,9 @@ func (handler *GetByEmailHandler) Process(_ context.Context, evt event.Persisted
 	handler.mx.Lock()
 	defer handler.mx.Unlock()
 
-	userEvent, ok := evt.Envelope.Message.(*Event)
+	userEvent, ok := evt.Message.(*Event)
 	if !ok {
-		return fmt.Errorf("user.GetByEmailHandler: unexpected event type, %T", evt.Envelope.Message)
+		return fmt.Errorf("user.GetByEmailHandler: unexpected event type, %T", evt.Message)
 	}
 
 	switch kind := userEvent.Kind.(type) {