diff --git a/.github/workflows/source.yml b/.github/workflows/source.yml
index e87a22a4f1..a2d0adbbef 100644
--- a/.github/workflows/source.yml
+++ b/.github/workflows/source.yml
@@ -31,7 +31,7 @@ jobs:
     runs-on: ubuntu-20.04
     steps:
     - uses: actions/checkout@v2
-    - uses: s-weigand/setup-conda@v1
+    - uses: s-weigand/setup-conda@v1.0.5
       with:
         update-conda: true
         conda-channels: conda-forge