Migration from t3-env

Migrating from t3-env to nevr-env is straightforward. The core API is compatible, with nevr-env adding plugins, vault, and CLI features.

Quick Migration

Before (t3-env)

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

export const env = createEnv({
  server: {
    DATABASE_URL: z.string().url(),
    NODE_ENV: z.enum(["development", "production", "test"]),
  },
  client: {
    NEXT_PUBLIC_API_URL: z.string().url(),
  },
  clientPrefix: "NEXT_PUBLIC_",
  runtimeEnv: process.env, 
});

After (nevr-env)

import { createEnv } from "nevr-env";
import { z } from "zod";

export const env = createEnv({
  server: {
    DATABASE_URL: z.string().url(),
    NODE_ENV: z.enum(["development", "production", "test"]),
  },
  client: {
    NEXT_PUBLIC_API_URL: z.string().url(),
  },
  clientPrefix: "NEXT_PUBLIC_",
  runtimeEnv: process.env, 
});

Key Differences

1. Package Name

Just one package to install and import:

- import { createEnv } from "@t3-oss/env-nextjs";
+ import { createEnv } from "nevr-env";

2. No Framework-Specific Packages

t3-env has separate packages for each framework. nevr-env uses one unified package:

- @t3-oss/env-nextjs
- @t3-oss/env-core
+ nevr-env

Feature Comparison

Feature	t3-env	nevr-env
Schema validation	✅	✅
Server/client split	✅	✅
Standard Schema	✅	✅
Extends	✅	✅
emptyStringAsUndefined	✅	✅
skipValidation	✅	✅
onValidationError	✅	✅
onInvalidAccess	✅	✅
experimental__runtimeEnv	✅	✅
createFinalSchema	✅	✅
Plugin system	❌	✅
Auto-discovery	❌	✅
CLI wizard	❌	✅
Encrypted vault	❌	✅
Dev command wrapper	❌	✅

Taking Advantage of New Features

Add Plugins

Replace manual schemas with plugins:

- server: {
-   DATABASE_URL: z.string().url().refine(
-     (url) => url.startsWith("postgres://"),
-     "Must be PostgreSQL URL"
-   ),
-   STRIPE_SECRET_KEY: z.string().startsWith("sk_"),
- },
+ plugins: [
+   postgres(),
+   stripe(),
+ ],

Use the CLI

# Check your configuration
npx nevr-env check

# Fix missing variables interactively
npx nevr-env fix

# Run dev with env loaded
npx nevr-env dev -- npm run dev

Enable Vault for Team

# Generate key
npx nevr-env vault keygen

# Push .env to vault
npx nevr-env vault push

# Teammates pull
npx nevr-env vault pull

Full Migration Example

Original t3-env Setup

// env.mjs
import { createEnv } from "@t3-oss/env-nextjs";
import { z } from "zod";

export const env = createEnv({
  server: {
    DATABASE_URL: z.string().url(),
    STRIPE_SECRET_KEY: z.string().min(1),
    STRIPE_WEBHOOK_SECRET: z.string().min(1),
    NODE_ENV: z.enum(["development", "production", "test"]),
  },
  client: {
    NEXT_PUBLIC_APP_URL: z.string().url(),
    NEXT_PUBLIC_STRIPE_PUBLISHABLE_KEY: z.string().min(1),
  },
  clientPrefix: "NEXT_PUBLIC_",
  runtimeEnv: process.env,
});

Migrated nevr-env Setup

// env.ts
import { createEnv, postgres, stripe } from "nevr-env";
import { z } from "zod";

export const env = createEnv({
  plugins: [
    postgres(),
    stripe({ 
      webhook: true,
      publishableKey: true,
    }),
  ],
  server: {
    NODE_ENV: z.enum(["development", "production", "test"]),
  },
  client: {
    NEXT_PUBLIC_APP_URL: z.string().url(),
  },
  clientPrefix: "NEXT_PUBLIC_",
  runtimeEnv: process.env,
});

Benefits of migrated version:

• 📦 Less code (plugins handle schemas)
• 🔍 Auto-discovery for DATABASE_URL
• 🛠️ CLI support for fixing missing vars
• 🔐 Vault support for team sharing
• ✅ Same type safety and validation