Yeah, I'm interested in this too.

I'm trying something like the following, but it doesn't seem to work.

import { env as clientEnv } from "@/lib/env/client";
import { env as serverEnv } from "@/lib/env/server";

// ...

I already submitted a PR for this, so basically, it is as simple as just importing the env file in next.config.ts.

import type { NextConfig } from "next";
 
// Import env here to validate during build.
import "./app/env";
 
const nextConfig: NextConfig = {
  /** ... */
};

@chungweileong94 I am already importing it into my next.config.ts file and it doesn’t work for me. See my previous comment.

I am using Next.js 15 canary with the turbo flag.

@chungweileong94 I am already importing it into my next.config.ts file and it doesn’t work for me. See my previous comment.

I am using Next.js 15 canary with the turbo flag.

Can you provide a small repo for it?

@jferrettiboke
I'm using Next,js 15 with turbo and just importing, as @chungweileong94 said, worked for me.

I renamed next.config.js to next.config.ts and env.js to env.ts. (the latter is not necessary here, I think)

In next.config.ts:
replace this: await import("./src/env.js");
with this: import "./src/env";
Check that we don't use import() here!

Of course you use own path like ./app or else.

Thanks @chungweileong94 @phl23! I was importing in another way. It now works for me.

Before:

import type { NextConfig } from "next";
import { env as clientEnv } from "@/lib/env/client";
import { env as serverEnv } from "@/lib/env/server";

const nextConfig: NextConfig = {
  /* config options here */
};

export default nextConfig;

After:

import type { NextConfig } from "next";
import "@/lib/env/client";
import "@/lib/env/server";

const nextConfig: NextConfig = {
  /* config options here */
};

export default nextConfig;

I'm encountering experimental warnings when running bun dev with my setup.

Environment:

• Node.js LTS: v22.12.0
• npm: v10.9.0

When I switch to the latest Node.js version (v23), the warnings are gone. But I prefer to use the LTS version rather than the latest version.

Is there any way silence or suppress these warnings without switching from the LTS version to latest version of Node.js?

env.ts

import { createEnv } from '@t3-oss/env-nextjs'
import { z } from 'zod'

export const env = createEnv({
  server: {
    DATABASE_URL: z.string().url(),
  },
  experimental__runtimeEnv: process.env,
})

next.config.ts
   
import type { NextConfig } from 'next';
import '@/lib/env';
   
const nextConfig: NextConfig = {};
   
export default nextConfig;

Output:

bun dev
$ next dev --turbopack
(node:42916) ExperimentalWarning: CommonJS module /../src/lib/env.ts is loading ES Module /../node_modules/@t3-oss/env-nextjs/dist/index.js using require().
Support for loading ES Module in require() is an experimental feature and might change at any time
(Use `node --trace-warnings ...` to show where the warning was created)
   ▲ Next.js 15.1.2 (Turbopack)
   - Local:        http://localhost:3000
   - Network:      http://10.0.19.188:3000
   - Environments: .env