diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index b4fece12..71a8605c 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -2,13 +2,21 @@
 
 name: MLGO CI
 
-on: [push, repository_dispatch, pull_request]
+permissions:
+  contents: read
+
+on:
+  push:
+    branches:
+      - 'main'
+  repository_dispatch:
+  pull_request:
 
 jobs:
   LicenseCheck:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: ./check-license.sh
   Envvars:
     runs-on: ubuntu-latest
@@ -46,17 +54,17 @@ jobs:
           - task: Test
             cmd: pytest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Install Python With Cached pip Packages
         if: needs.Envvars.outputs.do_cache == '1'
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
           cache: 'pipenv'
           cache-dependency-path: Pipfile.lock
       - name: Install Python, no cache
         if: needs.Envvars.outputs.do_cache == '0'
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
       - name: Install Pipenv
diff --git a/compiler_opt/es/es_worker.py b/compiler_opt/es/es_worker.py
deleted file mode 100644
index 22b3ff42..00000000
--- a/compiler_opt/es/es_worker.py
+++ /dev/null
@@ -1,40 +0,0 @@
-# coding=utf-8
-# Copyright 2020 Google LLC
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-"""Worker for ES Training."""
-
-import gin
-from typing import List
-from compiler_opt.distributed import worker
-from compiler_opt.rl import corpus
-
-
-@gin.configurable
-class ESWorker(worker.Worker):
-  """Temporary placeholder worker.
-  Each time a worker is called, the function value
-  it will return increases."""
-
-  def __init__(self, arg, *, kwarg):
-    self._arg = arg
-    self._kwarg = kwarg
-    self.function_value = 0.0
-
-  def temp_compile(self, policy: bytes,
-                   samples: List[corpus.ModuleSpec]) -> float:
-    if policy and samples:
-      self.function_value += 1.0
-      return self.function_value
-    else:
-      return 0.0
diff --git a/compiler_opt/rl/corpus.py b/compiler_opt/rl/corpus.py
index 5ca8f4c3..dc44dd0f 100644
--- a/compiler_opt/rl/corpus.py
+++ b/compiler_opt/rl/corpus.py
@@ -420,7 +420,7 @@ def reset(self):
   def sample(self, k: int, sort: bool = False) -> List[ModuleSpec]:
     """Samples `k` corpus elements, optionally sorting by size descending.
 
-    Use load_corpus_element to get LoadedModuleSpecs - this allows the user
+    Use load_module_spec to get LoadedModuleSpecs - this allows the user to
     decide how the loading should happen (e.g. may want to use a threadpool)
     """
     # Note: sampler is intentionally defaulted to a mutable object, as the
diff --git a/compiler_opt/rl/env.py b/compiler_opt/rl/env.py
index 1bd96afb..904fd388 100644
--- a/compiler_opt/rl/env.py
+++ b/compiler_opt/rl/env.py
@@ -359,6 +359,7 @@ def reset(self, module: corpus.LoadedModuleSpec):
     self._clang_generator.send(None)
     # pytype: disable=attribute-error
     self._iclang, self._clang = self._clang_generator.send(module)
+    # pytype: enable=attribute-error
     return self._get_observation()
 
   def step(self, action: np.ndarray):