fusion-env

Typed environment-variable validation for the Fusion stack — a thin @t3-oss/env-core + Zod wrapper that parses and validates a runtime environment into a fully-typed object. Source-published (Model A): consumers bundle the TypeScript directly.

Validate once, typed everywhere

You call createAppEnv(process.env) once at boot. It validates the raw environment against a Zod schema and hands back a typed object — so the rest of the app reads env.SERVER_URL (a string | undefined) instead of poking at process.env.SERVER_URL (a string | undefined that lied to you). Misconfigured values fail fast, at startup, with a clear error — not deep in a request three hours later.

Two things come for free from @t3-oss/env-core:

• Server / client separation — VITE_-prefixed vars are the only ones a browser bundle may read; server secrets can't leak into client code.
• Empty strings are undefined — a blank SERVER_URL= is treated as "not set" rather than an invalid value.

Install

Published to GitHub Packages under the @tikab-interactive scope, so an .npmrc with a read:packages token is required:

@tikab-interactive:registry=https://npm.pkg.github.com
//npm.pkg.github.com/:_authToken=${NPM_TOKEN}

bun add @tikab-interactive/fusion-env @t3-oss/env-core zod

@t3-oss/env-core and zod are peer dependencies — install them in the consuming app.

Next steps

• The schema — every variable fusion-env validates, and how the server/client split works.
• Usage — wiring createAppEnv into your app and reading typed values.