Frameworks

Validate environment variables in Next.js, Nuxt, Vite, TanStack Start, and Bun with ArkEnv.

ArkEnv works in any JavaScript or TypeScript project. When you build full-stack applications, client bundles must never receive server secrets. The framework packages below enforce that boundary during development and production builds.

Choose your framework to get started:

Next.js

@arkenv/nextjs, withArkEnv, and build-time validation.

Nuxt

@arkenv/nuxt module, runtime config, and NUXT_PUBLIC_ keys.

Vite

@arkenv/vite-plugin transform mode and VITE_ keys.

TanStack Start

@arkenv/vite-plugin / @arkenv/rsbuild-plugin with tanstackStart() and createServerFn.

Bun fullstack dev server

@arkenv/bun-plugin for Bun bundler and fullstack apps.

Vanilla

Use ArkEnv in a plain Node.js or Bun project.

How hosts enforce the boundary

Frameworks use compile-time AST transforms or host runtime adapters:

Framework	Integration strategy	Client bundle output	SSR and server validation	Public env without rebuild (Docker)
Next.js	Host adapter + codegen (`@arkenv/nextjs`)	Generated runtime proxy	Process boot (`process.env`)	Requires rebuild for `NEXT_PUBLIC_*`
Nuxt	Nitro plugin (`@arkenv/nuxt`)	Dynamic `runtimeConfig` hydration	Nitro server boot gate	Yes (via Nitro `runtimeConfig`)
Vite	AST build transform (`@arkenv/vite-plugin`)	Inlined public literals + throwing stubs	Full `@arkenv/core` at server boot	Requires rebuild for `VITE_*`
TanStack Start	AST build transform (`@arkenv/vite-plugin` / `@arkenv/rsbuild-plugin`)	Inlined public literals + throwing stubs	Full `@arkenv/core` at server boot	Requires rebuild for `VITE_` / `PUBLIC_`
Bun	Bundler AST transform (`@arkenv/bun-plugin`)	Inlined public literals + throwing stubs	Full `@arkenv/core` at server boot	Requires rebuild for `BUN_PUBLIC_*`

Vite, TanStack Start, and Bun evaluate two module graphs in full-stack and SSR apps. Application code imports @arkenv/core (or @arkenv/standard); the plugin rewrites the client graph so public keys inline and server secrets become throwing stubs. Next.js and Nuxt use host adapters (@arkenv/nextjs, @arkenv/nuxt) with dedicated entrypoints and codegen or runtimeConfig hydration.

ArkEnv keeps the validation engine (@arkenv/core / @arkenv/standard) as an optional peer of each host adapter. You install the engine you use; the adapter does not bundle either runtime. That keeps host packages lean and lets you pair any adapter with ArkType or a Standard Schema validator.

Loading `.env` files

ArkEnv does not read .env files. Something else must load them before arkenv() runs.

Next.js, Nuxt, Vite, and Bun already load .env* files. On plain Node (20.6+), use the built-in --env-file flag:

Terminal

node --env-file=.env dist/index.js

For TypeScript in development, pass the same flag to your usual runner:

Terminal

tsx --env-file=.env src/index.ts

For NestJS applications, @nestjs/cli 11+ supports nest start --env-file .env — follow the Use with NestJS guide.

After values are in process.env (or a custom record), arkenv() validates them.