diff --git a/.github/workflows/book.yml b/.github/workflows/book.yml
index 748e627..393ae5d 100644
--- a/.github/workflows/book.yml
+++ b/.github/workflows/book.yml
@@ -15,6 +15,19 @@ jobs:
           toolchain: stable
           override: true
 
+      - name: Cache dependencies
+        uses: actions/cache@v2
+        env:
+          cache-name: cache-mdbook
+        with:
+          path: |
+            ~/.cargo/.crates.toml
+            ~/.cargo/.crates2.json
+            ~/.cargo/bin
+            ~/.cargo/registry/index
+            ~/.cargo/registry/cache
+          key: ${{ runner.os }}-build-${{ env.cache-name }}-0.2 }}
+
       - name: Install mdbook
         run: |
           (test -x $HOME/.cargo/bin/cargo-install-update || cargo install cargo-update)