diff --git a/.github/workflows/md5.yml b/.github/workflows/md5.yml
index 3f2befd..991c6bf 100644
--- a/.github/workflows/md5.yml
+++ b/.github/workflows/md5.yml
@@ -47,6 +47,8 @@ jobs:
           toolchain: ${{ matrix.toolchain }}
           target: ${{ matrix.target }}
           override: true
+      # NOTE: using `marcopolo/cargo` fork to support the `working-directory` attribute
+      # See: https://github.com/actions-rs/cargo/pull/59
       - uses: marcopolo/cargo@master
         with:
           command: test
diff --git a/.github/workflows/sha1.yml b/.github/workflows/sha1.yml
index ef3d58a..6639223 100644
--- a/.github/workflows/sha1.yml
+++ b/.github/workflows/sha1.yml
@@ -63,6 +63,8 @@ jobs:
           toolchain: ${{ matrix.rust }}
           target: ${{ matrix.target }}
           override: true
+      # NOTE: using `marcopolo/cargo` fork to support the `working-directory` attribute
+      # See: https://github.com/actions-rs/cargo/pull/59
       - uses: marcopolo/cargo@master
         with:
           command: test
diff --git a/.github/workflows/sha2.yml b/.github/workflows/sha2.yml
index 881d483..c46d1e1 100644
--- a/.github/workflows/sha2.yml
+++ b/.github/workflows/sha2.yml
@@ -67,6 +67,8 @@ jobs:
           toolchain: ${{ matrix.rust }}
           target: ${{ matrix.target }}
           override: true
+      # NOTE: using `marcopolo/cargo` fork to support the `working-directory` attribute
+      # See: https://github.com/actions-rs/cargo/pull/59
       - uses: marcopolo/cargo@master
         with:
           command: test