diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..5e180ee
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,32 @@
+name: CI
+
+on:
+  pull_request:
+    branches:
+      - main
+      - develop
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements.txt
+
+      - name: Install struct-ia
+        run: |
+          pip install git+https://github.com/struct-ai/struct-ai.git@feat/20-github-action-analyse-pr
+
+      - name: Verify Python sources
+        run: python -m compileall -q src
diff --git a/.github/workflows/pr_analysis.yml b/.github/workflows/pr_analysis.yml
new file mode 100644
index 0000000..789d76c
--- /dev/null
+++ b/.github/workflows/pr_analysis.yml
@@ -0,0 +1,52 @@
+name: PR Analysis
+
+on:
+  pull_request:
+    branches:
+      - main
+    types:
+      - opened
+      - synchronize
+      - reopened
+
+# Minimal permissions: read code, write PR comments.
+permissions:
+  contents: read
+  pull-requests: write
+
+jobs:
+  struct-ia-review:
+    name: struct-ia — Clean Architecture Analysis
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          # Full history required for git diff against origin/main
+          fetch-depth: 0
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+
+      - name: Install dependencies
+        run: pip install "git+https://github.com/struct-ai/struct-ai.git@feat/20-github-action-analyse-pr"
+
+      - name: Run struct-ia PR analysis
+        run: python -m struct_ai.entrypoints.github_action.main
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GITHUB_REPOSITORY: ${{ github.repository }}
+          PR_NUMBER: ${{ github.event.number }}
+          GITHUB_WORKSPACE: ${{ github.workspace }}
+          OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
+          # Uncomment the provider you want to use instead of OpenAI:
+          # ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
+          # GOOGLE_API_KEY: ${{ secrets.GOOGLE_API_KEY }}
+          # MISTRAL_API_KEY: ${{ secrets.MISTRAL_API_KEY }}
+          # OLLAMA_BASE_URL: ${{ secrets.OLLAMA_BASE_URL }}
+          #
+          # Set to "false" to make violations warnings-only (CI won't fail).
+          STRUCT_IA_FAIL_ON_VIOLATION: "true"
diff --git a/.struct-ia.yaml b/.struct-ia.yaml
index 4a706b3..3fbff33 100644
--- a/.struct-ia.yaml
+++ b/.struct-ia.yaml
@@ -19,3 +19,10 @@ layers:
   - name: entrypoints
     paths:
       - entrypoints
+
+# Démonstration struct-ia : fichiers avec layer_violation volontaire (imports inter-couches).
+# - domain/model.py, domain/ports.py → import infrastructure
+# - domain/settings_mirror.py → import entrypoints
+# - infrastructure/repository.py, infrastructure/cli_bridge.py → import entrypoints
+
+provider: openai
diff --git a/src/app/domain/ports.py b/src/app/domain/ports.py
new file mode 100644
index 0000000..945bd3f
--- /dev/null
+++ b/src/app/domain/ports.py
@@ -0,0 +1,8 @@
+"""Intentional violation: domain re-declares infrastructure coupling."""
+
+# struct-ia: expect layer_violation — domain imports infrastructure.
+from app.infrastructure.repository import SqlUserRepository
+
+
+def make_repository() -> SqlUserRepository:
+    return SqlUserRepository()
diff --git a/src/app/domain/settings_mirror.py b/src/app/domain/settings_mirror.py
new file mode 100644
index 0000000..d1afdf7
--- /dev/null
+++ b/src/app/domain/settings_mirror.py
@@ -0,0 +1,8 @@
+"""Intentional violation: domain must not depend on entrypoints (outer layer)."""
+
+# struct-ia: expect layer_violation — domain imports entrypoints.
+from app.entrypoints.main import APP_CONFIG
+
+
+def get_configured_db_path() -> str:
+    return str(APP_CONFIG.get("db_path", "db/users.json"))
diff --git a/src/app/infrastructure/cli_bridge.py b/src/app/infrastructure/cli_bridge.py
new file mode 100644
index 0000000..0db611d
--- /dev/null
+++ b/src/app/infrastructure/cli_bridge.py
@@ -0,0 +1,10 @@
+"""Intentional violation: infrastructure must not depend on entrypoints."""
+
+from typing import Any, Dict
+
+# struct-ia: expect layer_violation — infrastructure imports entrypoints.
+from app.entrypoints.main import create_user_from_http_payload
+
+
+def bootstrap_user_from_cli_payload(payload: Dict[str, Any]) -> None:
+    create_user_from_http_payload(payload)