diff --git a/dist/index.js b/dist/index.js
index c91eee1f..c090b4a0 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -41777,6 +41777,7 @@ async function requestUploadURL(repoKey, sha) {
 
 
 
+
 // WarpBuild checkout snapshot cache: SHA-keyed tars of what the stock shallow fetch
 // produces. Hit = restore + skip the fetch; miss = upload after checkout. Keys are
 // immutable (no expiry). Fail-open: any error degrades to stock behavior.
@@ -41795,9 +41796,6 @@ function getMirrorCacheSkipReason(settings) {
         !process.env['WARPBUILD_HOST_URL']) {
         return SKIP_NOT_WARPBUILD;
     }
-    if (process.platform === 'win32') {
-        return 'Windows is not supported by the snapshot cache yet';
-    }
     const repoKey = process.env['GITHUB_REPOSITORY_ID'] || '';
     if (!repoKey) {
         return 'GITHUB_REPOSITORY_ID is not set';
@@ -41878,6 +41876,11 @@ async function setup(settings) {
 async function setupInner(settings) {
     const repoKey = process.env['GITHUB_REPOSITORY_ID'];
     const sha = settings.commit;
+    // The restore/upload paths shell out to `tar`; without it, fall back cleanly.
+    if (!(await which('tar', false))) {
+        info('tar not found on PATH; using standard checkout');
+        return false;
+    }
     const lookup = await lookupSnapshot(repoKey, sha);
     if (lookup.kind === 'disabled') {
         info('Snapshot cache is disabled by the backend for this organization');
diff --git a/src/warpbuild/mirror-cache.ts b/src/warpbuild/mirror-cache.ts
index dbeb476e..879a43f2 100644
--- a/src/warpbuild/mirror-cache.ts
+++ b/src/warpbuild/mirror-cache.ts
@@ -1,6 +1,7 @@
 /* eslint-disable i18n-text/no-en, import/no-unresolved -- upstream conventions; no TS import resolver configured */
 import * as core from '@actions/core'
 import * as exec from '@actions/exec'
+import * as io from '@actions/io'
 import * as fs from 'fs'
 import * as os from 'os'
 import * as path from 'path'
@@ -38,9 +39,6 @@ export function getMirrorCacheSkipReason(
   ) {
     return SKIP_NOT_WARPBUILD
   }
-  if (process.platform === 'win32') {
-    return 'Windows is not supported by the snapshot cache yet'
-  }
   const repoKey = process.env['GITHUB_REPOSITORY_ID'] || ''
   if (!repoKey) {
     return 'GITHUB_REPOSITORY_ID is not set'
@@ -127,6 +125,12 @@ async function setupInner(settings: IGitSourceSettings): Promise<boolean> {
   const repoKey = process.env['GITHUB_REPOSITORY_ID'] as string
   const sha = settings.commit
 
+  // The restore/upload paths shell out to `tar`; without it, fall back cleanly.
+  if (!(await io.which('tar', false))) {
+    core.info('tar not found on PATH; using standard checkout')
+    return false
+  }
+
   const lookup = await api.lookupSnapshot(repoKey, sha)
 
   if (lookup.kind === 'disabled') {