diff --git a/.github/workflows/vangers_linux_build.yml b/.github/workflows/vangers_linux_build.yml
index 94609f98..970f0a12 100644
--- a/.github/workflows/vangers_linux_build.yml
+++ b/.github/workflows/vangers_linux_build.yml
@@ -2,37 +2,38 @@ name: Vangers Linux Build
 
 on: [push, pull_request]
 
+env: 
+  VANGE_RS_REF: 950a5dd30e374c5e8cd28d7742eec814301c4ed2
+
 jobs:
   build:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
 
+    - name: vange-rs -- cache build
+      uses: actions/cache@v2
+      id: vange-rs-cache-build
+      with:
+        path: vange-rs/target/release/libvangers_ffi.a
+        key: ${{ env.VANGE_RS_REF }}
+
     - name: install rustup toolchain
+      if: steps.vange-rs-cache-build.outputs.cache-hit != 'true'
       uses: actions-rs/toolchain@v1
       with:
         toolchain: stable
 
     - name: vange-rs -- download
-      # uses: actions/checkout@v2
-      # with:
-      #   repository: kvark/vange-rs
-      #   ref: 439d89a
-      #   token: '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'
-      #   path: vange-rs
-      #   # fetch-depth: 1
-      run: git clone --depth 1 https://github.com/kvark/vange-rs vange-rs
-
-
-    # - name: vange-rs -- cache build
-    #   uses: actions/cache@v2
-    #   id: vange-rs-cache-build
-    #   with:
-    #     path: vange-rs/target/release/release/libvangers_ffi.a
-    #     key: 439d89a # TODO
+      if: steps.vange-rs-cache-build.outputs.cache-hit != 'true'
+      uses: actions/checkout@v2
+      with:
+        repository: kvark/vange-rs
+        ref: ${{ env.VANGE_RS_REF }}
+        path: vange-rs
 
     - name: vange-rs -- build
-      # if: steps.vange-rs-cache-build.outputs.cache-hit != 'true'
+      if: steps.vange-rs-cache-build.outputs.cache-hit != 'true'
       run: cargo build --release
       working-directory: vange-rs/lib/ffi
       
diff --git a/.github/workflows/vangers_windows_64_build.yml b/.github/workflows/vangers_windows_64_build.yml
index 6bb6eff1..e9dcc0ca 100644
--- a/.github/workflows/vangers_windows_64_build.yml
+++ b/.github/workflows/vangers_windows_64_build.yml
@@ -2,6 +2,9 @@ name: Vangers Windows 64bit Build
 
 on: [push, pull_request]
 
+env: 
+  VANGE_RS_REF: 950a5dd30e374c5e8cd28d7742eec814301c4ed2
+
 jobs:
   build:
     runs-on: windows-latest
@@ -24,27 +27,35 @@ jobs:
         mingw-w64-x86_64-dlfcn'
     - uses: actions/checkout@v1
 
+    - name: vange-rs -- cache build
+      uses: actions/cache@v2
+      id: vange-rs-cache-build
+      with:
+        path: vange-rs/target/release/libvangers_ffi.a
+        key: ${{ env.VANGE_RS_REF }}
+
     - name: vange-rs -- install rustup
+      if: steps.vange-rs-cache-build.outputs.cache-hit != 'true'
       uses: actions-rs/toolchain@v1
       with:
             toolchain: stable
             target: x86_64-pc-windows-gnu
             default: true
+
     - name: vange-rs -- configure rustup
-      run: rustup default stable-x86_64-pc-windows-gnu
+      if: steps.vange-rs-cache-build.outputs.cache-hit != 'true'
+      run: rustup default stable-x86_64-pc-windows-gnu      
 
-    # TODO: revision 
     - name: vange-rs -- download
-      run: git clone --depth 1 https://github.com/kvark/vange-rs vange-rs
-      # uses: actions/checkout@v2
-      # with:
-      #   repository: kvark/vange-rs
-      #   ref: 439d89a
-      #   path: vange-rs
-      #   # fetch-depth: 1
+      uses: actions/checkout@v2
+      with:
+        repository: kvark/vange-rs
+        ref: ${{ env.VANGE_RS_REF }}
+        path: vange-rs
 
     - name: vange-rs -- build
-      run: cargo build --release
+      if: steps.vange-rs-cache-build.outputs.cache-hit != 'true'
+      run: cargo build --release      
       working-directory: vange-rs/lib/ffi
 
     - name: vange-rs -- copy artifacts to prefix