nextenv-cli

A drop-in replacement for dotenv-cli that loads .env files the Next.js way — via @next/env's loadEnvConfig.

Use it when you want a prelude command that populates process.env for a Next.js app (or any child process) using exactly the same cascade and precedence rules that next dev / next start apply internally. No divergence between the pre-Next environment and the environment Next sees.

Install

pnpm add -D @asmala/nextenv-cli @next/env
# or
npm i -D @asmala/nextenv-cli @next/env

@next/env is a peer dependency (>=13). In a Next.js project it's already available transitively via next, but declaring it explicitly aligns the version with your Next install. Node >=20.19 is required.

Usage

// package.json
{
  "scripts": {
    "dev":   "nextenv -- next dev",
    "start": "nextenv -- next start"
  }
}

Migrating from dotenv-cli:

- "dev":   "dotenv -c -- next dev",
- "start": "dotenv -c -- next start",
+ "dev":   "nextenv -- next dev",
+ "start": "nextenv -- next start",

The -- separator is optional (nextenv next dev works too). There are no flags; nextenv does one thing.

How it picks dev vs prod

nextenv inspects the command args — if the token dev appears anywhere, the development cascade is loaded; otherwise the production cascade. This matches what Next itself does internally:

Command	Cascade loaded
nextenv -- next dev	.env.development.local → .env.local → .env.development → .env
nextenv -- next start	.env.production.local → .env.local → .env.production → .env
nextenv -- next build	.env.production.local → .env.local → .env.production → .env

Earlier files in the list take precedence. Existing process.env values are not overridden by .env files (Next's default).

When NODE_ENV=test, @next/env uses the test cascade and skips .env.local — same behavior nextenv exposes, since it just defers to loadEnvConfig.

What it does not do

• No flag surface. No -e, no -c, no -p. If you need those, stick with dotenv-cli.
• It doesn't set NODE_ENV for the child — Next sets it itself based on the subcommand.
• It doesn't inspect or rewrite variables. Next does that (e.g. NEXT_PUBLIC_* inlining).

License

MIT — see LICENSE.