diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 7d3de01e6..ff15f8772 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -24,6 +24,8 @@ jobs:
       with:
         workspaces: |
           zeroidc/
+        key: ${{ runner.os }}-cargo-${{ hashFiles('zeroidc//Cargo.lock') }}
+        shared-key: {{ runner.os }}-cargo-
     - name: make
       run: make
     - name: selftest
@@ -53,6 +55,8 @@ jobs:
       with:
         workspaces: |
           zeroidc/
+        key: ${{ runner.os }}-cargo-${{ hashFiles('zeroidc//Cargo.lock') }}
+        shared-key: {{ runner.os }}-cargo-
     - name: make
       run: make
     - name: selftest
@@ -82,6 +86,8 @@ jobs:
       with:
         workspaces: |
           zeroidc/
+        key: ${{ runner.os }}-cargo-${{ hashFiles('zeroidc//Cargo.lock') }}
+        shared-key: {{ runner.os }}-cargo-
     - name: setup msbuild
       uses: microsoft/setup-msbuild@v1.1.3
     - name: msbuild
diff --git a/.github/workflows/validate.yml b/.github/workflows/validate.yml
index 4a07243aa..e0c9fecfd 100644
--- a/.github/workflows/validate.yml
+++ b/.github/workflows/validate.yml
@@ -27,6 +27,8 @@ jobs:
       with:
         workspaces: |
           zeroidc/
+        key: ${{ runner.os }}-cargo-${{ hashFiles('zeroidc//Cargo.lock') }}
+        shared-key: {{ runner.os }}-cargo-
 
     - name: validate-1m-linux
       env: