Latest @rescript-lang.org beta slaps hard! github.com/rescript-lan...

Help us test our new build system which comes enabled by default with the first ReScript v12 beta. npm create rescript-app@next forum.rescript-lang.org/t/ann-rescri...

A solid demo of how ReScript integrates seamlessly with popular JS tools!

Next up we have a talk about the new build system, Rewatch by Jaap Frolich.

Good morning! We are currently kicking off this year's ReScript Retreat with a talk about editor tooling by @z-th.bsky.social and @nojaf.com.

Amazing work by @hyeseong.kim !

I wrote a blog post about using the React compiler with #rescript. You can check it out here: blog.nojaf.com/2025/03/23/r.... Things are going smoothly so far!

We just landed a new (experimental) feature for v12 - nested record definitions! Records is a corner stone in ReScript. However, they can't be nested without explicit definitions. Until now! Will be especially useful for deeply nested records (like options objects) not intended to be reused.

We are happy to announce that there will be another "ReScript Retreat" in 2025, once again in Vienna, Austria. Check out this new blogpost to get an idea what we did last year. rescript-lang.org/blog/retreats

Looks like a massive perf improvement could land on the playground! Great job @hyeseong.kim !

Go read this amazing blog post from @vlkpack.com to learn more about all the tools that work great with #rescript!

@z-th.bsky.social has made an amazing job introducing #ReScript, go watch this deeply interesting video!

Perfect when you want to experiment with some #rescript code right in the browser!

Records are powerful, but you need explicit definitions for them. We're experimenting with allowing inline record definitions nested inside a record type definition. This will make some of the common use cases for records more ergonomic.

The new dot completion also works for objects. Objects are structurally typed, doesn't need a type definition, and are quite useful in some scenarios. Completion for object fields will be more ergonomic and get better discoverability with this addition.

With the new dot completion enhancements in our editor tooling you'll now get completions from the Option module when autocompleting on a record field that's an optional value, instead of just no completions like before.

Happy new year! We're almost ready to release an exciting editor feature - dot completion everywhere! "." will now trigger completions for more than just record fields. Example: you'll get completions for pipeable functions from the module of that type. Examples and videos ⬇️

I've been playing around with @rescript-lang.org for a React project I'm working on and I'm super impressed with how far it's come since I last checked it out! Also between ReScript and @gleam.run I'm absolutely spoiled when it comes to error messages

Type inference is simple but powerful. The compiler will infer each type that's unknown by usage. A consequence of this is that prop drilling is really simple, because you rarely have to annotate props. Just using the prop in the component defining it is usually enough.

In ReScript, pipes are normally used for chaining fn calls instead of method chaining with dots like in JS. This is a common gotcha for JS/TS devs who come to ReScript. To ease the transition we're experimenting with letting the editor tooling complete pipes also via dots.

In ReScript you can put expressions almost anywhere. Assign expressions to variables, put them anywhere in JSX, put them directly into function arguments, etc. Massive readability and productivity boosters, and you'll love it if you haven't written in a language with it before.

Did a quick stream on my WebAPI #ReScript progress: www.youtube.com/live/MC-dbM-...

Since v11, ReScript has support for explicit partial application of functions using the "..." syntax at the end of the function call. Partial application of functions is useful in many scenarios, and this explicit syntax makes code easier to read and reason about.

Pipes are one of the most powerful concepts in ReScript. Pipes let you build function chains easily, with great support for type inference, and great editor support like autocomplete. It's just a syntax transform, so it compiles to regular, efficient JS function calls.

ReScript has first class support for tagged template literals since v11.1. A useful JS technique that's important for interop, and lends itself well to some pretty interesting use cases!

Dynamic imports shipped in ReScript v11. You can easily import both entire file modules, as well as single functions. For file modules, you simply await the module itself. For single functions, you use the `import` function. Makes things like React.lazy easy to use.

Good documentation fosters great collaboration. I really hope my latest #ReScript adventure takes off: rescript-lang.github.io/experimental...

JSX is a 1st class language feature in ReScript. Since v11.1 you've been able to use any createElement-style JSX transform you'd like with ReScript. Image shows Preact, but there are examples in the community even for non-client side fws, like emitting plain HTML server side.

ReScript ships with native async/await support that also compiles to async/await in JavaScript. You can pattern match directly on the await, and handle errors in the pattern match as well. No need to wrap things manually in try/catch, the compiler still emits the right thing.

We shipped a %todo extension point in v11.1. It makes it easy to postpone implementing something but not have the compiler block you continuing working. It'll produce a warning by default, and it's easy to configure the compiler so that it emits a hard error in for example CI.

In v12 we're hoping to ship Rewatch, ReScript's new build system, made by Jaap and Roland. Below is compiling a 375k LoC repo using the current build system vs Rewatch. 1. Current build system: 33.8s 2. Rewatch: 12.27s Speedup by a factor of 2.75 (!) in this example.

We'll ship our new standard library Core by default in v12. Core replaces the current standard lib and most of Belt, with one unified experienced that's built to look and feel more like the JavaScript APIs you're used to, while not sacrificing ergonomics.

We're further closing the syntax gap between ReScript and JavaScript in in v12: - First class regex syntax (previously needed wrapping in %re("<pattern>")) - Remainder operator - Use +, -, / and * for any number type, dedicated operators per type not needed And more coming!

Another new feature in v12 - variant type spreads in pattern matching! This allows you to refine variant types and easily match on a whole subset type without having to enumerate it. This was always possible with polyvariants, and now also with regular variants.

In v12, several new features come together to enable powerful new use cases. Dict pattern matching and with untagged variants make it easy to hand write JSON decoders/encoders with great DX, and also get efficient and readable JS output. More power, less complexity.

Quite a few new useful features coming to ReScript in v12! For example, first class syntax and pattern matching for dicts! Dicts are an important tool when interoping with JS. Cristiano has also done massive work improving the efficiency of the emitted JS, which can be seen in the output here.

Amazing DX improvement, kudos @hyeseong.kim !!

We want to remove all frictions for newcomers, especially coming from the JS/TS world! Great work on editor support by @z-th.bsky.social, as always!

Go follow ReScript main contributors and users! go.bsky.app/H2xfW7S

Hello everybody, #ReScript is finally and officially on Bluesky!