diff --git a/.github/workflows/CICD.yml b/.github/workflows/CICD.yml
index 74f1d8ce0..6623686b2 100644
--- a/.github/workflows/CICD.yml
+++ b/.github/workflows/CICD.yml
@@ -67,7 +67,7 @@ jobs:
     - name: Install `rust` toolchain
       uses: actions-rs/toolchain@v1
       with:
-        toolchain: nightly
+        toolchain: nightly-2022-03-21
         default: true
         profile: minimal
     - name: Install `cargo-udeps`
@@ -483,7 +483,7 @@ jobs:
     - name: Install `rust` toolchain
       uses: actions-rs/toolchain@v1
       with:
-        toolchain: nightly
+        toolchain: nightly-2022-03-21
         default: true
         profile: minimal # minimal component installation (ie, no documentation)
     - name: Test
diff --git a/.github/workflows/GnuTests.yml b/.github/workflows/GnuTests.yml
index 1f24f3045..fbd6f4c0f 100644
--- a/.github/workflows/GnuTests.yml
+++ b/.github/workflows/GnuTests.yml
@@ -218,7 +218,7 @@ jobs:
     - name: Install `rust` toolchain
       uses: actions-rs/toolchain@v1
       with:
-        toolchain: nightly
+        toolchain: nightly-2022-03-21
         default: true
         profile: minimal # minimal component installation (ie, no documentation)
         components: rustfmt