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Comment by mattkrick | Hacker News Reader

Personally, I let vscode do typechecking on open files & have a pre-commit git hook to typecheck changed files.

When it comes to starting up a development server & building the client, there's a huge cost to repeatedly typechecking the same 1000+ files. By cutting out typechecking & only compiling, I can reduce the webpack client build from 40 seconds to 3 seconds (using sucrase).

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I'm answering to you but this is really for most siblings:

I maintain a fairly large TS code base (nodejs backend). I think a full rebuild is 1:30 on my relatively recent laptop (i7-8650U, lots of RAM). But in practice I always use tsc -w and compile is mostly instant after editing a file (I do have to wait whenever I launch the command after I boot, but after that, it's fast enough).

tsc now support incremental compilation too, though I haven't played with it too much as I'm happy with watch mode.

Incremental compilation is _okay_ but it seems to perform full rebuilds if the previous build is _too_ old which is weird- meaning that more builds than expected take the entire time to complete. Nonetheless I use it for all of my builds. On the other hand this may just be because of the spiraling nature of type inference, where TS needs to re-examine a large amount of the program from a change that appears simple.

Personally I only have a small number of projects that take more than 10-20 seconds to compile, but those ones are painful. I should probably do the same with -w for those.

What if not everyone else on your team is paying attention to their editor's warnings? What if the LS's async response doesn't come fast enough? What if, god forbid, you have to change something on a different computer?

If it's not in your CI/CD scripts, it's not actually getting checked.

> I can reduce the webpack client build... to 3 seconds

This is about 10x longer than any interaction with a computer should be.

> If it's not in your CI/CD scripts, it's not actually getting checked.

You can make a similar argument and say you must write in a sound type system language, and TS typesystem is unsound.

Sorry, I don't understand the analogy. Yes, TS allows some bugs through, and that's a problem too. But that's also a far cry from "always rely on humans to run complex processes in a consistent way."

This is similar to what I do (although I use esbuild), however like an idiot I just run tsc manually so obviously I forget sometimes and it takes 10 minutes to realise the build failed.

Not great... I'm ashamed but it's just me on this project atm.

edit: misread parent originally

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