diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 4da3050..8304a8f 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -47,6 +47,9 @@ jobs:
       - name: Lint with Sqlfluff
         run: make lint-sql
 
+      - name: Quality check with pyscn
+        run: make lint-quality
+
   type-check:
     runs-on: ubuntu-latest
     steps:
diff --git a/.gitignore b/.gitignore
index 3f2cbf1..9437f13 100644
--- a/.gitignore
+++ b/.gitignore
@@ -53,6 +53,7 @@ coverage.xml
 .hypothesis/
 .pytest_cache/
 cover/
+.pyscn/
 
 # Translations
 *.mo
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 66b218f..924d696 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -41,6 +41,15 @@ repos:
     - id: interrogate
       pass_filenames: false  # config (incl. exclude paths) lives in pyproject.toml
 
+# pyscn (code quality gate: complexity, dead code, clones, circular deps)
+- repo: local
+  hooks:
+    - id: pyscn
+      name: pyscn
+      entry: uv run pyscn check
+      language: system
+      pass_filenames: false
+
 # sqlfluff
 - repo: https://github.com/sqlfluff/sqlfluff
   rev: 3.5.0
diff --git a/Makefile b/Makefile
index 9b7c924..f81de20 100644
--- a/Makefile
+++ b/Makefile
@@ -39,7 +39,7 @@ lock:
 format:
 	uv run ruff format --check .
 
-lint: lint-python lint-sql lint-docstrings
+lint: lint-python lint-sql lint-docstrings lint-quality
 
 lint-python:
 	uv run ruff check --output-format=github .
@@ -50,6 +50,9 @@ lint-sql:
 lint-docstrings:
 	uv run interrogate
 
+lint-quality:
+	uv run pyscn check .
+
 type:
 	uv run pyrefly check
 
diff --git a/README.md b/README.md
index b19b7ed..6b59d08 100644
--- a/README.md
+++ b/README.md
@@ -100,6 +100,7 @@ The checks contained in this repo include (in the order in which they run):
 * `pyrefly` is used for static type checking
 * `sqlfluff` checks and fixes sql formatting and linting
 * `interrogate` checks docstring coverage
+* `pyscn` checks code quality (complexity, dead code, clones, circular deps)
 * `uv` checks on valid and aligned pyproject.toml and uv.lock files
 * `commitlint` enforces commit message conforms to [conventional commit](https://www.conventionalcommits.org/en/v1.0.0/) format
 
diff --git a/pyproject.toml b/pyproject.toml
index bbe47e0..9a7636e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -29,6 +29,7 @@ dev = [
     "nox >=2024.4.15,<2025",
     "prek >=0.1.0,<1",
     "pyrefly >=1.2.0,<2",
+    "pyscn >=1.31.2,<2",
     "pytest >=8.3.2,<9",
     "pytest-cov >=5.0.0,<6",
     "python-semantic-release >=10.0.0,<11",
@@ -52,6 +53,39 @@ verbose = 1
 exclude = ["tests", "docs", "noxfile.py"]
 
 
+#######
+# Pyscn
+#######
+# Code quality gate: complexity, dead code, clones, coupling, architecture.
+# This only sets what deviates from pyscn's own defaults (or is left as an
+# explicit toggle). Full option reference: https://docs.codescan.dev/configuration/reference/
+
+[tool.pyscn.output]
+format = "text"                 # Default output format: text, json, yaml, csv, html
+show_details = false             # Show detailed breakdown by default
+sort_by = "complexity"           # Default sort: name, complexity, risk
+min_complexity = 1               # Minimum complexity to report
+directory = ""                   # Output directory for reports (empty = default .pyscn/reports/, gitignored)
+
+[tool.pyscn.complexity]
+enabled = true                   # Enable complexity analysis
+low_threshold = 9                # Functions with complexity ≤ 9 are low risk
+medium_threshold = 19            # Functions with complexity 10-19 are medium risk
+                                  # Functions with complexity ≥ 20 are high risk
+max_complexity = 0               # Maximum allowed complexity (0 = no limit). Must be 0 or > medium_threshold;
+                                  # the CI gate's own limit (10) is set independently via `pyscn check --max-complexity`
+report_unchanged = true          # Report functions with complexity = 1
+
+[tool.pyscn.dead_code]
+enabled = true                   # Enable dead code detection; see reference link above for tunable options
+
+[tool.pyscn.cbo]
+enabled = true                   # Enable class coupling (CBO) analysis; see reference link above for tunable options
+
+[tool.pyscn.architecture]
+enabled = false                  # This project is a flat single-package library, not a layered app
+
+
 ##########
 # Coverage
 ##########
diff --git a/uv.lock b/uv.lock
index 718b662..033c6f3 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1988,6 +1988,17 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/b3/6f/459f56dc345c32f8597acef13675e7e67679fb56bc3fd8f0a280eaeb8c02/pyrefly-1.3.0-py3-none-win_arm64.whl", hash = "sha256:3a3fb7c07dfb9b43d4205d8e85a83aaefc85377d0437dc8469c132836a8a7e5d", size = 14347403, upload-time = "2026-09-11T00:41:35.01Z" },
 ]
 
+[[package]]
+name = "pyscn"
+version = "1.31.2"
+source = { registry = "https://pypi.org/simple" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/7f/8f/da2c6b5e9c4f0b70ccb48fdfd0c0b96534ac0f5d2097c20f48664cf1c574/pyscn-1.31.2-py3-none-macosx_11_0_arm64.whl", hash = "sha256:87d0e0d1813c384345c3f7cc726678f095c975404f59039127f50a62e5708afa", size = 10232689, upload-time = "2026-09-10T09:12:49.765Z" },
+    { url = "https://files.pythonhosted.org/packages/76/26/8dafae4879b88453c4db396f73b102773453c21d05a99291ad193ac01451/pyscn-1.31.2-py3-none-manylinux_2_34_aarch64.whl", hash = "sha256:e07658e496fd0cd0ba60640f6e8cf0da316a1258a44a9790fd55535df0131b31", size = 10046867, upload-time = "2026-09-10T09:12:51.893Z" },
+    { url = "https://files.pythonhosted.org/packages/8a/f9/d7d125796d0e6db9d8103dc0174255354561f0abf89c004851afaabaddec/pyscn-1.31.2-py3-none-manylinux_2_34_x86_64.whl", hash = "sha256:55c6a22d4b1ee24628a62b06c9967d7e9b2619067097793172414e03c1505621", size = 11162333, upload-time = "2026-09-10T09:12:54.705Z" },
+    { url = "https://files.pythonhosted.org/packages/65/74/b70422a79032bf0d39fb8b7d5fd4b08fea03aede6424d288f3f55422742b/pyscn-1.31.2-py3-none-win_amd64.whl", hash = "sha256:c8349f184d40e16841466054738f5adacd8df4cba2e6458a80e7a0d8ec6e383f", size = 11630685, upload-time = "2026-09-10T09:12:57.287Z" },
+]
+
 [[package]]
 name = "pytest"
 version = "8.4.2"
@@ -2613,6 +2624,7 @@ dev = [
     { name = "nox" },
     { name = "prek" },
     { name = "pyrefly" },
+    { name = "pyscn" },
     { name = "pytest" },
     { name = "pytest-cov" },
     { name = "python-semantic-release" },
@@ -2633,6 +2645,7 @@ dev = [
     { name = "nox", specifier = ">=2024.4.15,<2025" },
     { name = "prek", specifier = ">=0.1.0,<1" },
     { name = "pyrefly", specifier = ">=1.2.0,<2" },
+    { name = "pyscn", specifier = ">=1.31.2,<2" },
     { name = "pytest", specifier = ">=8.3.2,<9" },
     { name = "pytest-cov", specifier = ">=5.0.0,<6" },
     { name = "python-semantic-release", specifier = ">=10.0.0,<11" },