diff --git a/.github/workflows/code_coverage.yml b/.github/workflows/code_coverage.yml
index d61ab757..ce84c4ff 100644
--- a/.github/workflows/code_coverage.yml
+++ b/.github/workflows/code_coverage.yml
@@ -11,7 +11,7 @@ jobs:
         uses: actions/checkout@v2
 
       - name: Set default toolchain
-        run: rustup default nightly
+        run: rustup default nightly-2021-03-23
       - name: Set profile
         run: rustup set profile minimal