diff --git a/.github/workflows/run-type-enforcer.yml b/.github/workflows/run-type-enforcer.yml
new file mode 100644
index 00000000..01a1cf7e
--- /dev/null
+++ b/.github/workflows/run-type-enforcer.yml
@@ -0,0 +1,32 @@
+name: Run Type Enforcer
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - "**.py"
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  type-safety:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
+        with:
+          ref: ${{ github.head_ref }}
+          fetch-depth: 0
+
+      - name: Set up Python
+        uses: actions/setup-python@v5.4.0
+        with:
+          python-version: "3.12"
+
+      - name: Install dependencies
+        run: pip install -r requirements.txt
+
+      - name: Type checker
+        run: mypy . --strict
diff --git a/flake.lock b/flake.lock
index 7f83f7a4..fe26ae69 100644
--- a/flake.lock
+++ b/flake.lock
@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1739923778,
-        "narHash": "sha256-BqUY8tz0AQ4to2Z4+uaKczh81zsGZSYxjgvtw+fvIfM=",
+        "lastModified": 1742388435,
+        "narHash": "sha256-GheQGRNYAhHsvPxWVOhAmg9lZKkis22UPbEHlmZMthg=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "36864ed72f234b9540da4cf7a0c49e351d30d3f1",
+        "rev": "b75693fb46bfaf09e662d09ec076c5a162efa9f6",
         "type": "github"
       },
       "original": {
@@ -37,11 +37,11 @@
         "nixpkgs": "nixpkgs_2"
       },
       "locked": {
-        "lastModified": 1739758351,
-        "narHash": "sha256-Aoa4dEoC7Hf6+gFVk/SDquZTMFlmlfsgdTWuqQxzePs=",
+        "lastModified": 1742471416,
+        "narHash": "sha256-Feo4W3kcJfEDnPfZdh0pt9SnMFCHBAukEDBZClEhe+Q=",
         "owner": "nix-community",
         "repo": "pyproject.nix",
-        "rev": "1329712f7f9af3a8b270764ba338a455b7323811",
+        "rev": "e6195836ac5d3d0e0c0c1a523afcf39f05554d20",
         "type": "github"
       },
       "original": {
diff --git a/pyproject.toml b/pyproject.toml
index d8fbb0c6..ba8df2b0 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -6,7 +6,7 @@ readme = "README.md"
 requires-python = ">=3.12"
 keywords = [ "software supply chain", "ssc", "dependencies", "npm",]
 classifiers = [ "Intended Audience :: Developers", "Topic :: Software Development :: Build Tools", "Programming Language :: Python :: 3", "License :: OSI Approved :: MIT License", "Operating System :: OS Independent",]
-dependencies = [ "attrs ==25.3.0", "cattrs == 24.1.2", "certifi ==2025.1.31", "charset-normalizer ==3.4.1", "exceptiongroup == 1.2.2", "GitPython ==3.1.44", "idna == 3.10", "markdown-it-py == 3.0.0", "numpy ==2.2.4", "pandas == 2.2.3", "platformdirs == 4.3.6", "pytest ==8.3.5", "python-dateutil == 2.9.0.post0", "pytz ==2025.1", "PyYAML == 6.0.2", "requests == 2.32.3", "requests-cache == 1.2.1", "six ==1.17.0", "tabulate == 0.9.0", "tqdm ==4.67.1", "typing_extensions == 4.12.2", "tzdata ==2025.1", "url-normalize == 1.4.3", "urllib3 ==2.3.0", "xmltodict == 0.14.2",]
+dependencies = [ "attrs ==25.3.0", "cattrs == 24.1.2", "certifi ==2025.1.31", "charset-normalizer ==3.4.1", "exceptiongroup == 1.2.2", "GitPython ==3.1.44", "idna == 3.10", "markdown-it-py == 3.0.0", "mypy ==1.15.0", "numpy ==2.2.4", "pandas == 2.2.3", "platformdirs == 4.3.6", "pytest ==8.3.5", "python-dateutil == 2.9.0.post0", "pytz ==2025.1", "PyYAML == 6.0.2", "requests == 2.32.3", "requests-cache == 1.2.1", "six ==1.17.0", "tabulate == 0.9.0", "tqdm ==4.67.1", "typing_extensions == 4.12.2", "tzdata ==2025.1", "url-normalize == 1.4.3", "urllib3 ==2.3.0", "xmltodict == 0.14.2",]
 [[project.authors]]
 name = "Raphina Liu"
 email = "raphina@kth.se"
diff --git a/requirements.txt b/requirements.txt
index a12d0d88..8b9e524c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,6 +6,7 @@ exceptiongroup==1.2.2
 GitPython==3.1.44
 idna==3.10
 markdown-it-py==3.0.0
+mypy==1.15.0
 numpy==2.2.4
 pandas==2.2.3
 platformdirs==4.3.6