diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6f24f4f..3972c4d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -67,7 +67,7 @@ jobs:
           - nightly
           # Don't remove this target; test coverage in `smoke.rs` relies on us
           # running at least one pinned toolchain.
-          - nightly-2020-12-01
+          - nightly-2021-06-01
 
     runs-on: ubuntu-20.04