Installation steps do not work for net new Next.js Apps

[dannyrb]

• https://create.t3.gg/en/usage/env-variables#adding-environment-variables
• https://env.t3.gg/docs/nextjs

I found the two sets of documentation above, and attempted to follow each of them in a net new next.js project with Typescript. Here are some issues I encountered:

• next.config.js does not build when using import/export syntax
• import.meta.url also requires module syntax
• One set of docs calls out "validating environment variables at runtime and buildtime", but the default setup does not seem to create buildtime checking
• If using jiti to add buildtime checking, next.config.js does not like module syntax, but client code does not like require / module.exports

[juliusmarminge]

Module syntax is based on you having package.json#type set to module. If you don't have that then you need to use the .mjs extension. This is true for any javascript file so I don't see why we should make this clear in our docs.

Validating schema on build is done by importing the env file into your next config as shown here: https://env.t3.gg/docs/nextjs#validate-schema-on-build-(recommended)

Checkout our example if you wanna see more details: https://github.com/t3-oss/t3-env/tree/main/examples/nextjs