INCIDENT RUNBOOK
Fix: Bundle Size Exceeded Worker Limit in Astro on Vercel
Comprehensive architectural post-mortem and verified configuration patch for astro deployed in vercel production environments.
Automated Remediation ProtocolUpdated for 2026 Production
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● Observed Terminal Error / Stack Trace
Error: Bundle size exceeded worker limit (1048576 bytes). @astrojs/ssr/dist/server/entry.js:1:1048576
Root Cause Analysis
The Astro framework is built on top of a modern web development paradigm, utilizing a islands architecture to optimize performance. However, when deployed to Vercel, the worker limit is exceeded due to the large bundle size generated by Astro's compilation process. This incompatibility arises from the fact that Vercel's worker limit is optimized for smaller, more modular codebases, whereas Astro's compilation process generates a larger bundle to facilitate its island-based architecture. As a result, the bundle size exceeds the worker limit, causing the deployment to fail.
● Configuration & Code Resolution
In `astro.config.js`, add the following configuration to optimize the bundle size:
+ export default {
+ //...
+ build: {
+ browser: {
+ // Enable code splitting to reduce bundle size
+ split: 'async'
+ }
+ }
+ }
Additionally, in `vercel.json`, add the following configuration to increase the worker limit:
+ {
+ "version": 2,
+ "builds": [
+ {
+ "src": "astro.config.js",
+ "use": "@vercel/static-build"
+ }
+ ],
+ "limits": {
+ "worker": {
+ "memory": 512,
+ "timeout": 30
+ }
+ }
+ }``Verification & Build Command
Run `npx astro build && npx vercel build` to verify that the bundle size is within the worker limit, then deploy to Vercel using `npx vercel deploy`