[_frog]

From my personal experience, Flow prioritises soundness in its type system, and thus can catch some bugs that TS won’t, but the TS tooling and editor support is drastically better than Flow’s.

Edit: oh and it’s worth noting that I’ve had much more luck finding TS definitions for third party packages than I have with Flow.

[MBCook]

Could you expand some more on the tooling/editor support?

I’ve only done a cursory look. My editor (IntelliJ) supports both to some level. Webpack/Babel do too.

I’m very new to writing React and modern front end JS so it’s quite possible there are things that I should be looking out for that I don’t even know about.

[nojvek]

Typescript compiler architecture is quite different to flows. Typescript was written from the get go to provide really fast and accurate intellisense to IDEs. The newer refactoring powers are super nice too. Most ides just ask typescripts language service “hey, my user’s cursor is here, what should I show for code completion?”

I think that’s what differentiates TS from flow. Typescript thought about the whole developers workflow while flow is just a compile time typechecker.

[Bahamut]

At this point, I think Flow clearly has a minority mindshare & is looked at more skeptically all around the JS ecosystem, and maybe even the React ecosystem based on what I see talked around. TS does a much better job integrating with existing JS and is much more practical about incremental updates whereas Flow bleeds all too easily into needing to add typing to a significant amount of code in order to add a type.

That's not to say that either TypeScript or Flow are perfect - they both are constraining with typing when it comes to composing functions last I checked.