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The Env Var That Won't Budge

A team builds one Docker image and promotes it from staging to production by changing only the container's environment variables.

REACT_MODULE // 0x42
// lib/config.ts
export const API_URL = process.env.NEXT_PUBLIC_API_URL;

// Same built image is promoted from staging to production
// by changing container env vars at deploy time.

What happens to API_URL inside the shipped client bundle?

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