diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 283828b..6734b12 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -26,7 +26,7 @@ jobs:
     name: Check fmt & build docs
     runs-on: ubuntu-latest
     steps:
-      - uses: taiki-e/checkout-action@v1
+      - uses: taiki-e/checkout-action@b13d20b7cda4e2f325ef19895128f7ff735c0b3d # v1
       - uses: Boshen/setup-rust@main
         with:
           components: rustfmt rust-docs
@@ -46,7 +46,7 @@ jobs:
             rust: 1.70.0
 
     steps:
-      - uses: taiki-e/checkout-action@v1
+      - uses: taiki-e/checkout-action@b13d20b7cda4e2f325ef19895128f7ff735c0b3d # v1
       - uses: Boshen/setup-rust@main
         with:
           save-cache: ${{ github.ref_name == 'main' }}
@@ -64,7 +64,7 @@ jobs:
     name: Check Wasm build
     runs-on: ubuntu-latest
     steps:
-      - uses: taiki-e/checkout-action@v1
+      - uses: taiki-e/checkout-action@b13d20b7cda4e2f325ef19895128f7ff735c0b3d # v1
       - uses: Boshen/setup-rust@main
         with:
           save-cache: ${{ github.ref_name == 'main' }}
@@ -79,7 +79,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: taiki-e/checkout-action@v1
+      - uses: taiki-e/checkout-action@b13d20b7cda4e2f325ef19895128f7ff735c0b3d # v1
       - uses: Boshen/setup-rust@main
         with:
           save-cache: ${{ github.ref_name == 'main' }}
@@ -102,7 +102,7 @@ jobs:
         os: [ubuntu-latest, macOS-latest, windows-latest]
 
     steps:
-      - uses: taiki-e/checkout-action@v1
+      - uses: taiki-e/checkout-action@b13d20b7cda4e2f325ef19895128f7ff735c0b3d # v1
       - uses: Boshen/setup-rust@main
         with:
           save-cache: ${{ github.ref_name == 'main' }}