.env.local.production |link| Jun 2026

In modern JavaScript applications (Next.js, Vite, Create React App), environment variables are managed via .env files. While .env , .env.local , .env.production , and .env.development are common, .env.local.production sits at a specific intersection: .

Here is a production-grade template for managing your env files. .env.local.production

for sensitive API keys, those keys would be checked into the repo and exposed to anyone with access to the code. By using the In modern JavaScript applications (Next

: On platforms like Vercel or Codemagic , you typically do not upload this file; instead, you enter the variables directly into the platform's UI. In modern JavaScript applications (Next.js

Not every framework supports this exact syntax. Here is the breakdown by ecosystem.