Stop using stinky `if (env === "development") ...` control flow checks

Do not use an environment control flow check like development, production or testing in your codebase.

Instead, whenever you want you app to behave differently in some context, use explicit env vars, making sure your app behaves as intendet.

Example

🚫 Bad example

// 🚫 DON'T
if (process.env.NODE_ENV === "development") {
  // Do something really stupid in development like
  // - Alternate upload dir in development
  // - Not wanting to actually send emails
  // - Printing extra debugging information
}

✅ The almost correct way to do it

// ✅ DO
// Check explicit env vars
// - Upload dir in development
saveFile(process.env.UPLOAD_DIR, file)

// - Not sending actual emails
if (not(process.env.SEND_EMAILS)) {
  return logger.debug("Preview email:", email)
}

// - Printing extra debugging information
const logger = new Logger({logLevel: process.env.LOG_LEVEL})
logger.debug(/*...*/)

*Almost? Yes, because:

Type-safe env vars

Also, create a config where you export the fucking env var as a constant, wrapped in a little helper to check if the env var is set and then either throw an error or set a default value, so you have type-safe enviroment vars!

const getEnvVar = (var: string, parser: ZodTypeAny) => { /* ... */ }
// Get and parse an env var with a  default if not set. Printing a waring when unset is advised.
export const SEND_MAILS = getEnvVar("SEND_MAILS", z.boolean().default(false)) 
export const UPLOAD_DIR = getEnvVar("UPLOAD_DIR", z.string().default("./uploads"))
export const TICK_RATE = getEnvVar("TICK_RATE", z.number().default(12))

FAQ*

*(Pronounced: fack-you)

What about testing environment?

What about it? 🤨

Just set the env vars in your test envrimontment like above. If you use local env files, use somhting like .env.test.local where you can set every configurable piece of your shitty software to the desired output.

But i am lazy

Then continue to write below average, unmaintainable, smelly code that piles up to an incomprehensable shit pile of technical debt!

Bye 🫶