diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b341585..9cb7160 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -36,7 +36,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install flake8 pytest
+          pip install flake8 pytest pytest-mock
           pip install --use-pep517 -r requirements.txt
       - name: Lint with flake8
         run: |
diff --git a/upgrade_deps.sh b/upgrade_deps.sh
index 339edc2..00de251 100755
--- a/upgrade_deps.sh
+++ b/upgrade_deps.sh
@@ -108,8 +108,10 @@ done
 BIN="$HOME/bin"
 DOWNLOADS="$HOME/downloads"
 
+PYTHON="python3.11"
 PIP="pip3.11"
-PIPENV="python3.11 -m pipenv"
+PIPENV="$PYTHON -m pipenv"
+FLAKE8="$PYTHON -m flake8"
 
 # Upgrade protoc
 
@@ -201,6 +203,16 @@ eval "$cmd"
 
 $PIPENV run python --version
 
+# Lint
+
+cmd="$FLAKE8 . --count --select=E9,F63,F7,F82 --show-source --statistics"
+if $interactive ; then askContinueYn "$cmd"; else echo -e "${cyan}$cmd${reset}";fi
+eval "$cmd"
+
+cmd="$FLAKE8 . --count --exit-zero --max-complexity=10 --max-line-length=200 --statistics"
+if $interactive ; then askContinueYn "$cmd"; else echo -e "${cyan}$cmd${reset}";fi
+eval "$cmd"
+
 # Test
 
 cmd="pytest"