.env.development

.env.local .env.*.local .env.production # But keep .env.development if it has safe defaults

: The universal fallback file containing defaults for all environments. Anatomy of a .env.development File

To get the most out of .env.development , follow these best practices: .env.development

Next.js has robust built-in support for environment-specific .env files.

Create React App provides built-in support for environment files. However, there's a critical security constraint: . However, there's a critical security constraint:

Different modern frontend frameworks and backend runtimes handle .env.development files with slight variations, particularly regarding how variables are exposed to the client-side code. 1. Node.js (Vanilla)

your-nextjs-app/ ├── .env.local # Local overrides (gitignored) ├── .env.development # Development defaults (committed) ├── .env.test # Testing defaults (committed) ├── .env.production # Production defaults (committed) └── next.config.js so do practices around .env.development .

// ✅ Use a backend proxy endpoint app.post('/api/create-checkout', (req, res) => // Server-side only — keys never leave the server const session = await stripe.checkout.sessions.create(...); );

.env.local is not loaded during testing to ensure test isolation and reproducibility.

As the ecosystem evolves, so do practices around .env.development .