diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 18c16e97d969b59c37195144af8ba50146d4c890..311bd1eb3efec06e2082e57ccdb8221fc49c5ebd 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -101,8 +101,13 @@ build_macosx_36:
   image: docker.idiap.ch/beat/ci.env.editor:0.0.1r0
   before_script:
     # safe keep artifacts as before_build.sh will erase those...
-    - export LC_ALL=C.UTF-8
-    - export LANG=C.UTF-8
+    - apt-get update > /dev/null
+    - apt-get install -y locales > /dev/null
+    - echo "en_US UTF-8" > /etc/locale.gen
+    - locale-gen en_US.UTF-8
+    - export LANG=en_US.UTF-8
+    - export LANGUAGE=en_US:en
+    - export LC_ALL=en_US.UTF-8
     - mv ${CONDA_ROOT}/conda-bld .
     - ./_ci/install.sh _ci master #updates ci support scripts
     - ./_ci/before_build.sh