</>
typescriptbeginner

Environment Variable Validation

Validate required environment variables at build time with type-safe access and descriptive errors.

typescript
function requireEnv(key: string): string {
  const value = process.env[key];
  if (!value) {
    throw new Error(
      `[env] Missing required environment variable: ${key}`
    );
  }
  return value;
}

export const env = {
  DATABASE_URL: requireEnv('DATABASE_URL'),
  NEXTAUTH_SECRET: requireEnv('NEXTAUTH_SECRET'),
  NEXTAUTH_URL: requireEnv('NEXTAUTH_URL'),
  STRIPE_SECRET_KEY: process.env.STRIPE_SECRET_KEY ?? '',
  ANALYTICS_ID: process.env.NEXT_PUBLIC_ANALYTICS_ID ?? '',
} as const;

// Validate at import time — fails fast during build
// import { env } from '@/lib/env';

Use Cases

  • App startup checks
  • CI pipeline validation
  • Config management

Tags

#environment#validation#config#typescript

Related Snippets

Similar patterns you can reuse in the same workflow.

typescriptbeginner

Environment Variable Validator

Validates required environment variables at startup and returns a typed config object or throws with missing keys.

Best for: App startup validation

#config#validation
typescriptbeginner

Type-Safe Configuration Loader

Load and validate configuration from environment variables with type coercion and required field checks.

Best for: Application configuration management

#nodejs#config
typescriptintermediate

Request Validation Schema Builder

Build a lightweight request validation layer with type inference for API endpoints.

Best for: API request body validation

#nodejs#validation
typescriptintermediate

Schema Validation with Zod-like Patterns

Build a minimal schema validation library inspired by Zod using TypeScript type inference.

Best for: API request validation

#nodejs#validation