Difference between

[unborn niche]

the -D flag stands for development dependencies, those are packages that are used only in the development process, and are not required in production. in your case, typescript is a build tool so its not needed at runtime, because node runs javascript not typescript

[winter dew]

So, is this important to put typescript into dev dependencies? I mean all good developers doing it, or just write npm install typescript without -D?

[unborn niche]

yes, putting it in the dev dependencies is the best call, otherwise it will just be shipped to production with other package which will just make ur production installs bigger

[winter dew]

Thank you!

[versed pollen]

I’ve seen your recent threads. You’re clearly new to Node/backend, which is normal. The problem isn’t being new, it’s the way you’re approaching it.

You’re asking meta questions instead of doing the work.

“Why TypeScript?”, “How auth works?”, “Zod vs Joi?”
These questions don’t unlock understanding. Building does.

Here’s the correct path, step by step:

1. Build one small API. Just Node + Express. No TypeScript.
2. Add one real flow: register → login → protected route.
3. Implement auth once, badly. Break it. Fix it.
4. Now rewrite the same project in TypeScript. The “why” will become obvious without anyone explaining it.
5. Add validation. Pick Zod or Joi randomly. Use it. You’ll learn when it hurts and when it helps.

Backend skill isn’t knowing what’s “used often”.
It’s knowing why something fails at 2am and how to fix it without panic.
Right now you’re browsing the menu instead of cooking.
Stop asking what chefs prefer. Make a dish, burn it, then ask why it tastes bad.

That’s how this actually clicks.

@winter dew

[winter dew]

I got it, thanks