.env.local.production -

Therefore, if your NODE_ENV was set to production , the framework would look for .env.production.local .

The difference is purely syntactical. Most modern frameworks prefer the former ( env.production.local ), but legacy systems or custom CI/CD pipelines might recognize the latter. If you have .env and .env.production , why introduce a third file? The answer lies in sensitive, environment-specific configuration . .env.local.production

# Real production (on the server) GENERATE_SOURCEMAP=false LOG_LEVEL=error GENERATE_SOURCEMAP=true # Override to debug bundled code LOG_LEVEL=debug # See everything during local build Therefore, if your NODE_ENV was set to production