Validate Your .env at Startup

The problem: process.env.DATABASE_URL is undefined. Your code uses it three layers deep. It fails at 3am.

The fix: Validate at startup using zod.

import { z } from "zod";

const envSchema = z.object({
  DATABASE_URL: z.string().url(),
  REDIS_URL: z.string().url(),
  API_KEY: z.string().min(10),
  NODE_ENV: z.enum(["development", "production", "test"]).default("development")
});

const env = envSchema.parse(process.env);

export default env;

If DATABASE_URL is missing or invalid, the app crashes on line 1. You see the error immediately.

In your app:

import env from "./env";

const db = pgClient(env.DATABASE_URL);  // Type-safe, validated

Never reach for as any on environment variables.

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