Skip to content
Layerfig Layerfig
GitHub

Dynamic Environment

If you maintain multiple environments (e.g., local, dev, staging, prod), you’ll have a separate configuration file for each one.

However, you can’t load them all at once:

import { ConfigBuilder, FileSource } from "@layerfig/config";
import { schema } from "./schema";

export const config = new ConfigBuilder({
  validate: (finalConfig) => schema.parse(finalConfig),
})
  .addSource(new FileSource("base.jsonc"))
  .addSource(new FileSource("local.jsonc"))
  .addSource(new FileSource("dev.jsonc"))
  .addSource(new FileSource("staging.jsonc"))
  .addSource(new FileSource("prod.jsonc"))
  .build();

This approach loads every file and merges them, with each subsequent layer overriding the previous.

A better solution is to use an environment variable (for example, APP_ENV=local|dev|staging|prod) and name your files accordingly:

import { ConfigBuilder, FileSource } from "@layerfig/config";
import { schema } from "./schema";

export const config = new ConfigBuilder({
  validate: (finalConfig) => schema.parse(finalConfig),
})
  .addSource(new FileSource("base.jsonc"))
  .addSource(new FileSource(`${process.env.APP_ENV}.jsonc`))
  .build();

Now, when you run your application with different APP_ENV values, it automatically loads the matching configuration file.