What are the recommended tools for managing environment variables in a Node.js project?

I'm building a mid-sized Node.js application and I want to manage environment variables properly across development, staging, and production environments.

Currently I'm using a basic .env file with the dotenv package, but I'm running into issues:

The problems I'm facing:

No type validation or default values

No clear separation between environments

Secrets accidentally committed to Git

No schema enforcement

I've seen libraries like dotenv-safe, envalid, and zod (with z.object for env), but I'm not sure which approach is recommended .

What are the best tools or patterns for:

Validating required environment variables at startup

Providing type safety (especially with TypeScript)

Managing multiple environments (dev/staging/prod)

Is the zod approach the current best practice, or are there better alternatives I should consider?