What is the common setup for a typescirpt backend project?

[small geyser]

the "vanilla"/typical approach is to use tsc to generate a folder for built code. similar to your second bullet, but actually configured (i don't think anyone intentionally has compiled files next to their source files)

tsx/ts-node are mostly for quick iteration, not for prod. not everyone uses it though

[fresh temple]

Yeah if you are going with the tsc approach, you would properly setup rootDir and outDir so for example your src/**/*.ts compiles to dist/**/*.js.

I typically don't use a bundler and go with tsc in production, and tsx during development.

[tropic nacelle]

what if I want to minify?

[small geyser]

you could get a bundler that supports that or an additional tool to do so

but typically you'll only need a bundler if you're packaging the project for, say, a browser environment

[tropic nacelle]

Can I get just one .d.ts file when I tsc? Now I'm getting multiple .d.ts files.

[small geyser]

you can but it's generally not recommended

it can lead to collisions if they were originally modules

why do you want a single file?

[tropic nacelle]

you mean it's normal?

ok

I thought there should be only one .d.ts

because those packages only have one

[small geyser]

yeah ts is just js with types, transpiling is just removing the types (for the most part, some older features do have some codegen)

so for each input ts, you'd gen an output js/d.ts

.ts ≈ .js + .d.ts

[small geyser]

if they're manually written, having just 1 is pretty common. that's a different situation though

[tropic nacelle]

So on developing a typescript backend , should I emit this declaration files? Seems no need then

[small geyser]

if it's an application, yeah no need

you'd need them if you wanted others to consume your code and get types, ie a library

[tropic nacelle]

So all librarys declaration files are manually written?

[small geyser]

no

a ts project can just generate d.ts from the exist ts source, but existing js projects won't have types (unless they use jsdoc), so they'd need manual d.ts

[tropic nacelle]

You mean , library written in js manually writes d.ts?

[small geyser]

yeah, sometimes they're too large for a rewrite to be easily feasible

[tropic nacelle]

Ok. what about library written in ts? how do they make d.ts?

[small geyser]

or the maintainers don't have the resources to migrate or aren't interested, other developers can publish types for that library via DefinitelyTyped

[small geyser]

they tell the compiler to emit d.ts

[tropic nacelle]

so they can emit just one d.ts?

Can tsc emit only one d.ts for the whole library?

[tropic nacelle]

@small geyser Man, I get it wrong. I thought that libraries written in ts also have just one d.ts 😅

When developing a typescript backend app, which value is correct for compilerOptions.module? NodeNext or ESNext?

[tropic nacelle]

!close

[small geyser]

if you're using node, then node16 or nodenext, nodenext is a moving target.