diff --git a/.buildkite/pipeline.sh b/.buildkite/pipeline.sh
index a4111e78..ea98a318 100755
--- a/.buildkite/pipeline.sh
+++ b/.buildkite/pipeline.sh
@@ -23,7 +23,8 @@ cat <<EOF
     command:
       - "python3 -m virtualenv .venv"
       - ". .venv/bin/activate"
-      - "python3 -m pip install pre-commit"
+      # https://github.com/pypa/virtualenv/issues/2257
+      - "python3 -m pip install pre-commit 'virtualenv<20.11.0'"
       - "pre-commit run --all-files"
     plugins:
       - docker#${BATFISH_DOCKER_PLUGIN_VERSION}:
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 9c253af8..adc38b85 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -11,11 +11,11 @@ repos:
     hooks:
     - id: black
 
-  #- repo: https://github.com/pycqa/isort
-  #  rev: 5.8.0
-  #  hooks:
-  #  - id: isort
-  #    args: ["--profile", "black", "--filter-files"]
+  - repo: https://github.com/pycqa/isort
+    rev: 5.8.0
+    hooks:
+    - id: isort
+      args: ["--profile", "black", "--filter-files"]
  
   - repo: https://github.com/humitos/mirrors-autoflake
     rev: v1.3