diff --git a/.gitea/actions/rust-cache/action.yml b/.gitea/actions/rust-cache/action.yml
index 1edb970..40f4fe1 100644
--- a/.gitea/actions/rust-cache/action.yml
+++ b/.gitea/actions/rust-cache/action.yml
@@ -7,43 +7,39 @@ inputs:
     description: Rust toolchain to install (e.g., stable, 1.75.0, nightly)
     default: stable
     required: false
+  cache-prefix:
+    description: Prefix for cache keys.
+    default: rust
+    required: false
 
 outputs:
   cache-hit:
     description: "Whether a cache entry was found"
-    value: ${{ steps.cache.outputs.cache-hit }}
+    value: ${{ steps.cache-restore.outputs.cache-hit }}
 
 runs:
   using: composite
   steps:
-    # Gitea Actions does not have Cargo.lock by default (cargo generates it on first build),
-    # and hashFiles() globs don't work reliably here. Use shell hashing instead.
     - name: Compute cache key
       id: cache-key
       shell: bash
       run: |
-        # Hash both files; if Cargo.lock doesn't exist yet, only Cargo.toml is hashed
-        HASH=$( (cat Cargo.toml 2>/dev/null || true; cat Cargo.lock 2>/dev/null || true) | sha256sum | cut -d' ' -f1)
+        {
+          printf 'toolchain=%s\n' '${{ inputs.toolchain }}'
+          find . \
+            \( -path './.git' -o -path './target' \) -prune -o \
+            \( -name Cargo.toml -o -name Cargo.lock -o -name rust-toolchain -o -name rust-toolchain.toml \) \
+            -type f -print0 \
+            | sort -z \
+            | xargs -0 sha256sum 2>/dev/null || true
+        } > /tmp/rust-cache-fingerprint
+        HASH=$(sha256sum /tmp/rust-cache-fingerprint | cut -d' ' -f1)
         echo "hash=$HASH" >> $GITHUB_OUTPUT
-        echo "fingerprint=$HASH" >> $GITHUB_ENV
+        echo "key=${{ inputs.cache-prefix }}-${{ runner.os }}-${{ runner.arch }}-${{ inputs.toolchain }}-$HASH" >> $GITHUB_OUTPUT
+        echo "restore-prefix=${{ inputs.cache-prefix }}-${{ runner.os }}-${{ runner.arch }}-${{ inputs.toolchain }}-" >> $GITHUB_OUTPUT
 
-    - name: Setup Rust
-      shell: bash
-      run: |
-        # If toolchain was cached, rustup will skip download — install still runs for metadata
-        curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs \
-          | sh -s -- -y --default-toolchain ${{ inputs.toolchain }}
-        # Add cargo bin to PATH for subsequent steps
-        echo "$HOME/.cargo/bin" >> $GITHUB_PATH
-
-    - name: Show sizes before cache
-      shell: bash
-      run: |
-        echo "=== ~/.cargo ===" && du -sh ~/.cargo 2>/dev/null || echo "(empty)"
-        echo "=== ~/.rustup ===" && du -sh ~/.rustup 2>/dev/null || echo "(empty)"
-
-    - name: Save cache
-      id: cache-save
+    - name: Restore Rust cache
+      id: cache-restore
       env:
         ACTIONS_CACHE_SERVICE_V2: "0"
       uses: https://gitea.com/actions/cache@v3
@@ -54,71 +50,13 @@ runs:
           ~/.rustup/toolchains
           ~/.rustup/settings.toml
           target
-        key: rust-linux-${{ steps.cache-key.outputs.hash }}
-        save-always: true
+        key: ${{ steps.cache-key.outputs.key }}
+        restore-keys: |
+          ${{ steps.cache-key.outputs.restore-prefix }}
 
-    - name: Debug print save outputs
+    - name: Setup Rust
       shell: bash
       run: |
-        echo "=== Save action outputs ==="
-        echo "cache-hit: '${{ steps.cache-save.outputs.cache-hit }}'"
-        echo "key: '${{ steps.cache-save.outputs.key }}'"
-        echo "=== All outputs ==="
-        env | grep -i ACTIONS_CACHE || echo "No ACTIONS_CACHE env vars in shell"
-
-    - name: Twirp probe via curl (debug)
-      shell: bash
-      env:
-        ACTIONS_CACHE_URL: ${{ env.ACTIONS_CACHE_URL }}
-        ACTIONS_RUNTIME_TOKEN: ${{ env.ACTIONS_RUNTIME_TOKEN }}
-        ACTIONS_RESULTS_URL: ${{ env.ACTIONS_RESULTS_URL }}
-      run: |
-        echo "=== Cache env vars ==="
-        echo "ACTIONS_CACHE_URL=$ACTIONS_CACHE_URL"
-        echo "ACTIONS_RUNTIME_TOKEN len=${#ACTIONS_RUNTIME_TOKEN}"
-        if [ -n "$ACTIONS_CACHE_URL" ]; then
-          HASH="${{ steps.cache-key.outputs.hash }}"
-          KEY="rust-linux-$HASH"
-          echo "=== Twirp v1: GetCacheEntryDownloadURL ==="
-          BODY=$(printf '{"key":"%s","restoreKeys":[],"version":"%s"}' "$KEY" "$HASH")
-          echo "POST $ACTIONS_CACHE_URL/twirp/github.actions.results.api.v1.CacheService/GetCacheEntryDownloadURL"
-          echo "Body: $BODY"
-          RESP=$(curl -si -X POST \
-            -H "Content-Type: application/json" \
-            -H "Authorization: Bearer $ACTIONS_RUNTIME_TOKEN" \
-            "$ACTIONS_CACHE_URL/twirp/github.actions.results.api.v1.CacheService/GetCacheEntryDownloadURL" \
-            -d "$BODY" \
-            2>&1)
-          echo "$RESP"
-          echo ""
-          echo "=== Also try list cache API ==="
-          LIST_RESP=$(curl -si \
-            -H "Authorization: Bearer $ACTIONS_RUNTIME_TOKEN" \
-            "$ACTIONS_CACHE_URL/_apis/artifactcache/caches?key=$KEY&version=$HASH" \
-            2>&1)
-          echo "$LIST_RESP"
-        else
-          echo "ACTIONS_CACHE_URL is empty"
-        fi
-
-    - name: Lookup same key immediately after save
-      id: cache-lookup
-      env:
-        ACTIONS_CACHE_URL: ${{ env.ACTIONS_CACHE_URL }}
-        ACTIONS_RUNTIME_TOKEN: ${{ env.ACTIONS_RUNTIME_TOKEN }}
-        ACTIONS_CACHE_SERVICE_V2: "0"
-        ACTIONS_RESULTS_URL: ${{ env.ACTIONS_RESULTS_URL }}
-      uses: https://gitea.com/actions/cache@v3
-      with:
-        path: ~/.cargo/registry
-        key: rust-linux-${{ steps.cache-key.outputs.hash }}
-        lookup-only: true
-
-    - name: Show sizes after cache
-      shell: bash
-      run: |
-        echo "=== ~/.cargo ===" && du -sh ~/.cargo 2>/dev/null || echo "(empty)"
-        echo "=== ~/.rustup ===" && du -sh ~/.rustup 2>/dev/null || echo "(empty)"
-        echo "save result: ${{ steps.cache-save.outputs.cache-hit }}"
-        echo "lookup result: ${{ steps.cache-lookup.outputs.cache-hit }}"
-        echo "ACTIONS_CACHE_URL=$ACTIONS_CACHE_URL"
+        curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs \
+          | sh -s -- -y --profile minimal --default-toolchain ${{ inputs.toolchain }}
+        echo "$HOME/.cargo/bin" >> $GITHUB_PATH
diff --git a/README.md b/README.md
index ab146c2..97a22f6 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@ Reusable Gitea Actions for Rust projects.
 
 ## actions/rust-cache
 
-Composite action that installs a Rust toolchain and caches cargo/crate dependencies.
+Composite action that restores Rust build caches, installs a Rust toolchain, and saves updated cargo/rustup/target caches after the job.
 
 ### Usage
 
@@ -18,7 +18,8 @@ jobs:
       - name: Setup Rust + Cache
         uses: https://git.ericxliu.me/eric/actions-rust/.gitea/actions/rust-cache@main
         with:
-          toolchain: stable  # optional, defaults to stable
+          toolchain: stable      # optional, defaults to stable
+          cache-prefix: rust     # optional, defaults to rust
 
       - run: cargo build --release
       - run: cargo test
@@ -26,14 +27,15 @@ jobs:
 
 ### What it does
 
-1. **Cache restore** — Restores `~/.cargo/registry`, `~/.cargo/git`, `~/.rustup/toolchains`, and `target/` using Gitea's native `actions/cache`.
-2. **Rust install** — Runs `rustup` to install or verify the requested toolchain.
-3. **PATH setup** — Appends `$HOME/.cargo/bin` to `$GITHUB_PATH` so cargo/rustc are available in subsequent steps.
+1. **Cache key** — Hashes root/workspace `Cargo.toml`, `Cargo.lock`, and `rust-toolchain*` files without relying on `hashFiles()`.
+2. **Cache restore/save** — Restores `~/.cargo/registry`, `~/.cargo/git`, `~/.rustup/toolchains`, and `target/` using Gitea's native `actions/cache`. The cache action saves updated paths in its post step after later build/test steps have populated them.
+3. **Rust install** — Runs `rustup` with the minimal profile to install or verify the requested toolchain.
+4. **PATH setup** — Appends `$HOME/.cargo/bin` to `$GITHUB_PATH` so cargo/rustc are available in subsequent steps.
 
 ### Cache key format
 
 ```
-rust-linux-{hash(Cargo.lock)}{hash(Cargo.toml)}
+{cache-prefix}-{runner.os}-{runner.arch}-{toolchain}-{hash(manifests/toolchain files)}
 ```
 
 Warm builds run in ~40–60s vs ~3min for a cold build.