diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index cd3b5a95..f72a7cce 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -43,12 +43,14 @@ jobs:
     strategy:
       matrix:
         python-version: ${{ fromJSON(needs.Envvars.outputs.version_matrix) }}
-        task: [Typecheck, Lint, Yapf, Test]
+        task: [Typecheck, Lint, Ruff, Yapf, Test]
         include:
           - task: Typecheck
             cmd: pytype -j auto .
           - task: Lint
             cmd: pylint --rcfile .pylintrc --recursive yes .
+          - task: Ruff
+            cmd: pipx run ruff==0.9.3 check
           - task: Yapf
             cmd: yapf . -drp
           - task: Test
diff --git a/Pipfile b/Pipfile
index 044b3d1e..1ce8f96d 100644
--- a/Pipfile
+++ b/Pipfile
@@ -15,9 +15,9 @@ dm-reverb = "==0.14.0"
 pylint = "==3.3.2"
 pytest = "==8.3.4"
 pytype = "==2024.10.11"
+ruff = "==0.9.3"
 yapf = "==0.43.0"
 
 [ci]
 joblib = "==1.4.2"
 shap = "==0.46.0"
-
diff --git a/compiler_opt/es/blackbox_evaluator.py b/compiler_opt/es/blackbox_evaluator.py
index 953a8152..35de7500 100644
--- a/compiler_opt/es/blackbox_evaluator.py
+++ b/compiler_opt/es/blackbox_evaluator.py
@@ -124,14 +124,12 @@ def __init__(self, train_corpus: corpus.Corpus,
   def get_results(
       self, pool: FixedWorkerPool, perturbations: List[policy_saver.Policy]
   ) -> List[concurrent.futures.Future]:
-    job_args = []
-    for perturbation in perturbations:
-      job_args.append({
-          'modules': self._train_corpus.module_specs,
-          'function_index_path': self._function_index_path,
-          'bb_trace_path': self._bb_trace_path,
-          'tflite_policy': perturbation
-      })
+    job_args = [{
+        'modules': self._train_corpus.module_specs,
+        'function_index_path': self._function_index_path,
+        'bb_trace_path': self._bb_trace_path,
+        'tflite_policy': perturbation
+      } for perturbation in perturbations]
 
     _, futures = buffered_scheduler.schedule_on_worker_pool(
         action=lambda w, args: w.compile_corpus_and_evaluate(**args),
diff --git a/compiler_opt/es/blackbox_test_utils.py b/compiler_opt/es/blackbox_test_utils.py
index 3a0a2ca4..404525e9 100644
--- a/compiler_opt/es/blackbox_test_utils.py
+++ b/compiler_opt/es/blackbox_test_utils.py
@@ -45,7 +45,7 @@ def compile(self, policy: policy_saver.Policy,
 
 class ESTraceWorker(worker.Worker):
   """Temporary placeholder worker.
-  
+
   This is a test worker for TraceBlackboxEvaluator that expects a slightly
   different interface than other workers.
   """
diff --git a/pyproject.toml b/pyproject.toml
index bdf58d2c..4fd17dba 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,12 @@
-# DO always create a tracking issue when allow-listing warnings
-# DO NOT disable warnings-as-error: warnings of today are tomorrow's evolvability blocker.
+[tool.ruff]
+line-length = 103
+lint.select = [ "C40", "C9", "E", "F", "PERF", "W" ]
+lint.ignore = [ "E722", "E731", "E741", "F401", "PERF203" ]
+lint.mccabe.max-complexity = 18
 
 [tool.pytest.ini_options]
+# DO always create a tracking issue when allow-listing warnings
+# DO NOT disable warnings-as-error: warnings of today are tomorrow's evolvability blocker.
 filterwarnings = [
   # Treat warnings as errors
   "error",