diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 9e15d18ad..1e8d04126 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -20,7 +20,22 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip setuptools six wheel
-          python -m pip install pytest-cov -r requirements.txt
+          python -m pip install mypy pytest-cov -r requirements.txt
+      # FIXME: #4052 fix mypy errors in other directories and add them here
+      - run: mypy --ignore-missing-imports
+           backtracking
+           bit_manipulation
+           blockchain
+           boolean_algebra
+           cellular_automata
+           computer_vision
+           fractals
+           fuzzy_logic
+           genetic_algorithm
+           geodesy
+           knapsack
+           networking_flow
+           scheduling sorts
       - name: Run tests
         run: pytest --doctest-modules --ignore=project_euler/ --ignore=scripts/ --cov-report=term-missing:skip-covered --cov=. .
       - if: ${{ success() }}