diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index 8cb36ea..ff26248 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -13,7 +13,7 @@ jobs:
     env:
       DATADEPS_ALWAYS_ACCEPT: true # bypass confirmation before downloading data (needed for CI)
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744
       - uses: julia-actions/setup-julia@latest
         with:
           version: '1'