diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index dff8ff6..6b83cae 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -4,7 +4,7 @@
 #   changes     — detect which paths changed (skips heavy jobs on workflow-only PRs)
 #   lint-core   — black, isort, ruff, mypy on packages/parser-core
 #   lint-free   — black, isort, ruff on packages/parser-free
-#   security    — bandit + pip-audit on both packages
+#   security    — bandit + pip-audit + xenon complexity gate
 #   test-core   — pytest with 91% coverage gate (Python matrix), needs lint-core
 #   test-free   — pytest on packages/parser-free, needs lint-free
 
@@ -207,6 +207,19 @@ jobs:
     - name: pip-audit — dependency vulnerability scan
       run: pip-audit -r requirements/base.txt --progress-spinner off -f json -o pip-audit-report.json
 
+    - name: Complexity gate (Xenon)
+      run: |
+        # table_detector.py: _detect_text_based_table grade E (score 32) — PDF heuristic hotspot,
+        #   pdfplumber word-coordinate coupling blocks safe decomposition without characterisation tests.
+        #   Temporary exclusion — remove once refactored. Tracked: https://github.com/longieirl/bankstatementprocessor/issues/98
+        # template_detector.py: get_detection_explanation grade D (score 22) — diagnostic method;
+        #   exhaustive path coverage of all scoring outcomes is inherent to its purpose. Stable exemption.
+        # commands/init.py: init_directories grade D (score 26) — CLI entrypoint orchestration;
+        #   complexity is setup sequencing (mkdir + sample file creation), not extractable decision logic. Stable exemption.
+        xenon --max-average A --max-modules B --max-absolute C \
+          --exclude "packages/parser-core/src/bankstatements_core/analysis/table_detector.py,packages/parser-core/src/bankstatements_core/templates/template_detector.py,packages/parser-core/src/bankstatements_core/commands/init.py" \
+          packages/parser-core/src
+
     - name: Upload security reports
       uses: actions/upload-artifact@v7
       if: always()
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 32905ad..8b961e8 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -42,7 +42,7 @@ pip install -e "packages/parser-free[test]"
 
 ```bash
 # Core tests with coverage
-pytest packages/parser-core/tests/ --cov=bankstatements_core --cov-fail-under=91
+pytest packages/parser-core/tests/ --cov=bankstatements_core --cov-fail-under=92
 
 # Free CLI smoke test
 bankstatements --version
@@ -63,15 +63,14 @@ bankstatements --init
 
 1. Fork the repository and create a branch
 2. Make changes following the code standards below
-3. **Write tests** — 91% coverage on `bankstatements-core` is enforced by CI
+3. **Write tests** — 92% coverage on `bankstatements-core` is enforced by CI
 4. Run quality checks:
    ```bash
    # From packages/parser-core/
-   black src tests
-   isort src tests
-   flake8 src tests --max-line-length=88 --extend-ignore=E203,W503
+   ruff format src tests
+   ruff check src tests
    mypy src --ignore-missing-imports
-   pytest tests/ --cov=bankstatements_core --cov-fail-under=91
+   pytest tests/ --cov=bankstatements_core --cov-fail-under=92
    ```
 5. Submit a PR — CI must pass (lint, boundary check, tests)
 
@@ -81,8 +80,8 @@ bankstatements --init
 
 ### Formatting
 
-- **Line length:** 88 characters (Black default)
-- **Imports:** organised by isort (stdlib → third-party → local)
+- **Line length:** 88 characters (ruff default)
+- **Imports:** organised by ruff (stdlib → third-party → local)
 
 ### Type Hints
 
@@ -110,13 +109,13 @@ def process_transaction(amount: Decimal, date: datetime) -> Transaction:
 
 ### Coverage Requirement
 
-**91% minimum on `bankstatements-core`** — enforced by CI. PRs that drop below this threshold will not be merged.
+**92% minimum on `bankstatements-core`** — enforced by CI. PRs that drop below this threshold will not be merged.
 
 ### Running Tests
 
 ```bash
-# All tests with coverage
-pytest packages/parser-core/tests/ --cov=bankstatements_core --cov-fail-under=91 -v
+# All tests with coverage (integration tests excluded by default)
+pytest packages/parser-core/tests/ --cov=bankstatements_core --cov-fail-under=92 -v
 
 # Specific file or test
 pytest packages/parser-core/tests/services/test_my_service.py -v
@@ -129,12 +128,29 @@ pytest packages/parser-core/tests/ -n auto
 pytest packages/parser-free/tests/ -v
 ```
 
+### Integration Tests
+
+Integration tests run the full processing pipeline against real PDFs on your local machine. They are excluded from the standard test run and never run in CI.
+
+```bash
+# First run — create your local snapshot baseline (requires PDFs in input/)
+cd packages/parser-core
+pytest tests/integration/ -m integration --snapshot-update -v
+
+# Subsequent runs — validate output against your baseline
+pytest tests/integration/ -m integration -v
+```
+
+The snapshot file (`tests/integration/snapshots/output_snapshot.json`) is gitignored — it is personal to your machine and input files.
+
 ### Test Organisation
 
 ```
 packages/parser-core/tests/
 ├── test_processor.py
 ├── test_app.py
+├── integration/          # local-only, requires real PDFs
+│   └── test_output_snapshot.py
 ├── services/
 ├── extraction/
 ├── domain/
@@ -158,9 +174,9 @@ Quick summary:
 
 ### Before Submitting
 
-- [ ] All tests pass with 91%+ coverage
-- [ ] Code is formatted (Black + isort)
-- [ ] Linting passes (Flake8, MyPy)
+- [ ] All tests pass with 92%+ coverage
+- [ ] Code is formatted (`ruff format`)
+- [ ] Linting passes (`ruff check`, MyPy)
 - [ ] New functionality has tests
 - [ ] No regressions in existing tests
 
@@ -168,9 +184,9 @@ Quick summary:
 
 Your PR must pass:
 
-- **lint-core** — Black, isort, Flake8, MyPy on `parser-core`
-- **lint-free** — Black, isort, Flake8 on `parser-free`
-- **test-core** — pytest with 91%+ coverage on `bankstatements-core`
+- **lint-core** — ruff, MyPy on `parser-core`
+- **lint-free** — ruff on `parser-free`
+- **test-core** — pytest with 92%+ coverage on `bankstatements-core`
 - **test-free** — pytest on `parser-free`
 - **boundary-check** — CI fails if `parser-free` imports `bankstatements_premium` or `src.licensing`
 - **security** — Bandit on both packages
diff --git a/requirements/ci.txt b/requirements/ci.txt
index d5c31b3..eb341d7 100644
--- a/requirements/ci.txt
+++ b/requirements/ci.txt
@@ -15,5 +15,4 @@ pip-licenses>=5.0.0
 PyYAML>=6.0
 
 # Complexity analysis
-radon==6.0.1
-mccabe==0.7.0
+xenon>=0.9.0