diff --git a/.github/workflows/adev-preview-build.yml b/.github/workflows/adev-preview-build.yml
index fd142ac98..c13ce4384 100644
--- a/.github/workflows/adev-preview-build.yml
+++ b/.github/workflows/adev-preview-build.yml
@@ -13,6 +13,9 @@ on:
 
 permissions: read-all
 
+env:
+  BAZEL_REPO_CACHE_PATH: '~/.cache/bazel_repo_cache'
+
 jobs:
   adev-build:
     runs-on: ubuntu-latest
@@ -27,6 +30,12 @@ jobs:
         with:
           node-version-file: '.node-version'
           cache: yarn
+      - uses: actions/cache@v4
+        with:
+          path: ${{ env.BAZEL_REPO_CACHE_PATH }}
+          key: bazel-repo-cache-${{ runner.os }}-${{ hashFiles('origin/WORKSPACE') }}
+          restore-keys: |
+            bazel-repo-cache-${{ runner.os }}-
       - run: yarn install
       - run: yarn build
       - run: chmod 755 build/dist/bin/adev/build/browser
diff --git a/tools/build.mjs b/tools/build.mjs
index cb1c5ddba..2e6eaf26f 100644
--- a/tools/build.mjs
+++ b/tools/build.mjs
@@ -4,6 +4,7 @@ import { chalk, argv } from 'zx';
 import {
   applyPatches,
   buildAdev,
+  setupBazelrc,
   copyLocalizedFiles,
   remove404HTML,
   copyRobots,
@@ -16,9 +17,9 @@ const { init = true } = argv;
 
 try {
   console.log(chalk.green('==== setup ===='));
-  await setup(init);
+  await setup({ init });
   console.log(chalk.green('==== preBuild ===='));
-  await preBuild();
+  await preBuild({ init });
   console.log(chalk.green('==== build ===='));
   await build();
   console.log(chalk.green('==== postBuild ===='));
@@ -28,18 +29,21 @@ try {
   process.exit(1);
 }
 
-async function setup(init) {
+async function setup({ init }) {
   await resetBuildDir({ init });
+  await setupBazelrc();
 }
 
-async function preBuild() {
-  // copy translated files
-  // console.log(chalk.cyan('Copy localized files...'));
-  // await copyLocalizedFiles();
+async function preBuild({ init }) {
+  if (init) {
+    // copy translated files
+    // console.log(chalk.cyan('Copy localized files...'));
+    // await copyLocalizedFiles();
 
-  // apply patches
-  console.log(chalk.cyan('Apply patches...'));
-  await applyPatches();
+    // apply patches
+    console.log(chalk.cyan('Apply patches...'));
+    await applyPatches();
+  }
 }
 
 async function build() {
diff --git a/tools/lib/common.mjs b/tools/lib/common.mjs
index 6cac3bfca..efd75ebe1 100644
--- a/tools/lib/common.mjs
+++ b/tools/lib/common.mjs
@@ -1,7 +1,8 @@
 import { watch } from 'chokidar';
+import { writeFile } from 'node:fs/promises';
 import { resolve } from 'node:path';
-import { $, cd, chalk, glob, within } from 'zx';
-import { initDir, cpRf, exists, sed, rmrf, rename } from './fileutils.mjs';
+import { $, cd, chalk, glob, os, within } from 'zx';
+import { cpRf, exists, initDir, rename, sed } from './fileutils.mjs';
 
 const rootDir = resolve(__dirname, '../');
 const aiojaDir = resolve(rootDir, 'aio-ja');
@@ -22,6 +23,31 @@ export async function resetBuildDir({ init = false }) {
   }
 }
 
+export async function setupBazelrc() {
+  await within(async () => {
+    const cachePath = process.env.BAZEL_REPO_CACHE_PATH || resolve(os.homedir(), '.cache/bazel_repo_cache');
+    const escapedCachePath = cachePath.replace(/\\/g, '\\\\');
+
+    cd(`${outDir}`);
+    const bazelrcContent = `
+  # Print all the options that apply to the build.
+  # This helps us diagnose which options override others
+  # (e.g. /etc/bazel.bazelrc vs. tools/bazel.rc)
+  build --announce_rc
+
+  # Avoids re-downloading NodeJS/browsers all the time.
+  build --repository_cache=${escapedCachePath}
+
+  # More details on failures
+  build --verbose_failures=true
+
+  # CI supports colors but Bazel does not detect it.
+  common --color=yes
+`;
+    await writeFile('.bazelrc.user', bazelrcContent);
+  });
+}
+
 export async function buildAdev() {
   await within(async () => {
     cd(`${outDir}`);