dotenvx

For searches like dotenvx run --env-file, the CLI option is -f, --env-file <paths...>. Put the separator before the command you are launching: dotenvx run --env-file .env.production -- node app.js. The short form is dotenvx run -f .env.production -- node app.js; multiple files can be passed as paths to the same option. For inline values, use dotenvx run --env HELLO=world -- npm start.

For project-local use, install it as a dev dependency with npm install dotenvx --save-dev and call it from package scripts or npx. Use npm install -g @dotenvx/dotenvx only when you intentionally want a machine-level CLI. Avoid copying examples with smart dashes; --env-file, --env, and the separator -- need normal hyphens.

Official source: Dotenvx README / dotenvx help run.