.env.development.local !!link!!

The .env.development.local file is a specialized environment variable file used primarily in modern web development frameworks like Next.js and Create React App. It is designed to allow developers to set local-only configuration values that apply specifically to their development environment.  Core Purpose 

However, for local development, you want to use a different API key or endpoint. In your .env.development.local file, you can add: .env.development.local

Benefits of .env.development.local:

DB_HOST=localhost
DB_PORT=5432
DB_USERNAME=myuser
DB_PASSWORD=mypassword
API_KEY= myapikey

Best practices

• Add .env.development.local to .gitignore (and confirm your team’s ignore templates include .env*.local).
• Keep secrets out of committed files; use .env.development.local or OS-level secret managers.
• Document required variables in a committed example file (e.g., .env.example or .env.development.example) without values.
• Prefer explicit names (REACT_APP_, NEXT_PUBLIC_) per framework conventions so build tools expose only intended variables.
• Avoid committing any .env*.local files to source control; treat them as ephemeral, personal configuration.
• Use the same variable names across environments for consistency; only values should differ.
• For CI and production, inject environment variables via the CI/dashboard secrets—never rely on .env.development.local.