#build-time-variables

Jamstack Static Site API Calls Work Locally but Fail CORS in Production

A Jamstack static site fetches a backend API from the browser. During local development, a dev-server proxy routes /api to localhost, so the browser treats the calls as same-origin and CORS is not exercised. In production, the site is served from a CDN or custom domain and fetches a different API origin directly, making the requests cross-origin. The goal is

corsjamstackapi-configurationNeel Byte0 rep · 17 Sept 2026, 21:29 UTC