diff --git a/README.md b/README.md
index 0431c57..aa32c1f 100644
--- a/README.md
+++ b/README.md
@@ -3,3 +3,5 @@
 * Reads node version file (.node-version) from project root
 * Only saves pnpm cache on the main branch
 * Restores pnpm cache on PR
+* Skips `actions/setup-node` on Alpine Linux (which only ships glibc
+  binaries) and uses the container's musl Node instead.
diff --git a/action.yml b/action.yml
index 9b41c39..65c2e2f 100644
--- a/action.yml
+++ b/action.yml
@@ -24,9 +24,21 @@ inputs:
 runs:
   using: composite
   steps:
+    # actions/setup-node only ships glibc Node binaries; on Alpine those can't
+    # run, so use the container's musl Node instead.
+    - name: Detect Alpine Linux
+      id: detect
+      if: runner.os == 'Linux'
+      shell: bash
+      run: |
+        if [ -f /etc/alpine-release ]; then
+          echo "is-alpine=true" >> "$GITHUB_OUTPUT"
+        fi
+
     - uses: pnpm/action-setup@41ff72655975bd51cab0327fa583b6e92b6d3061 # v4.2.0
 
     - uses: actions/setup-node@53b83947a5a98c8d113130e565377fae1a50d02f # v6.3.0
+      if: steps.detect.outputs.is-alpine != 'true'
       with:
         node-version-file: .node-version
         architecture: ${{ inputs.architecture }}