diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7000354..1e6d5f6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,7 +22,7 @@ jobs:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
       - name: Setup Rust toolchain
-        uses: dtolnay/rust-toolchain@stable
+        uses: dtolnay/rust-toolchain@4cda84d5c5c54efe2404f9d843567869ab1699d4 # stable
         with:
           toolchain: stable
           components: clippy
@@ -46,7 +46,7 @@ jobs:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
       - name: Setup Rust toolchain
-        uses: dtolnay/rust-toolchain@nightly
+        uses: dtolnay/rust-toolchain@4fd1da8b0805d2d2e936788875a7d65dbd677dc2 # nightly
         with:
           toolchain: nightly
           components: rustfmt