diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 7314efd..7e3618b 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -33,6 +33,10 @@ jobs:
     - name: Build the extension
       run: |
         set -eux
+        export LANG=en_US.UTF-8
+        export LANGUAGE=en_US:en
+        export LC_ALL=en_US.UTF-8
+
         python -m pip install .[test]
 
         jupyter labextension list