Use Bun with ReScript.
Currently alpha state software. You're encouraged to start using it, but please report all issues. There will be both bindings missing and some bindings will probably be wrong/suboptimal. We're going to work through the API surface as we go. Report all issues you find!
Template repo to get up and running quickly: https://github.com/zth/rescript-bun-starter
You need to be on ReScript v11 >=11.1.0
and Core >=1.3.0
. This is designed for uncurried mode so you should use that as well ("uncurried": true
in your bsconfig/rescript.json
).
Install rescript-bun
and @rescript/core
:
npm i rescript-bun @rescript/core
Include them in your rescript.json
:
{
"bs-dependencies": ["@rescript/core", "rescript-bun"]
}
rescript-bun
is namespaced, so you'll find all modules listed under the main module RescriptBun
.
You're strongly encouraged to open RescriptBun
globally, to get the best possible developer experience. You do that by adding this to your rescript.json
:
{
"bsc-flags": [
"-open RescriptCore",
"-open RescriptBun",
"-open RescriptBun.Globals"
]
}
Notice
-open RescriptBun.Globals
. This will expose all Bun globals. This might be a matter of taste, but I recommend opening it to get the best experience.
This will make all of Bun available to you without needing to dip into the RescriptBun
module explicitly.
This lib copies rescript-nodejs
for Bun's Node compatible bindings. Shout out to the maintainers of that project!
Here's a few examples of how it looks. More examples (often inspired by https://bun.sh/guides
) can be found in the playground/examples
directory in this repo.
To write tests using Bun's built in test runner, just open Test
and you'll have everything available to you to write your tests:
open Test
describe("Playing around with tests", () => {
test("addition works", () => {
expect(1 + 1)->Expect.toBe(2)
})
})
This will make all of Bun's testing utilities available to you in the global scope.
Here's setting up a simple web server.
let server = Bun.serve({
fetch: async (request, _server) => {
let userName =
request
->Request.headers
->Headers.get("x-user-name")
->Option.getWithDefault("Unknown user")
Response.make(`Hello ${userName}!`, ~options={status: 200})
},
})
let port =
server
->Bun.Server.port
->Int.toString
let hostName = server->Bun.Server.hostname
Console.log(`Server listening on http://${hostName}:${port}!`)
let password = "super-secure-pa$$word"
let bcryptHash = await Bun.Password.hash(
password,
~algorithm=BCryptAlgorithm({
cost: 4, // number between 4-31
}),
)
let isMatch = await Bun.Password.verify(password, ~hash)
let router = Bun.FileSystemRouter.make({
style: NextJs,
dir: "./pages",
origin: "https://mydomain.com",
assetPrefix: "_next/static/",
})
let matches = router->Bun.FileSystemRouter.match("/")
// Rewrite all <div> to <section>
let rewriter = HTMLRewriter.make()->HTMLRewriter.on(
"*",
{
element: element => {
if element.tagName === "div" {
element.tagName = "section"
}
},
},
)
let response = await fetch("https://bun.sh")
let transformedResponse = rewriter->HTMLRewriter.transform(response)
let html = await transformedResponse->Response.text
Console.log(html)
Currently, bindings exist for the most common things. There's still a good amount of bindings missing. Some bindings will be covered as we go along, while others won't be added.
- Globals
- Bun
- Tests
- Fs
- Stream (some stream utils already exist in Globals + Bun)
- Path
- AsyncHooks
- Crypto
- Buffer
- Child_process (needs Stream?)
- HTML Rewriter
- Os
- Sqlite
- Perf hooks
- StringDecoder
- Readline (needs Stream?)
- WorkerThreads
- FFI
- Util
- SupportsColors
- Timers
- Tls
- Tty
- Assert
- Diagnostics channel
- Dns
- Domain
- Events
- JSC
- Module
- Net
- VM
- WS (already multiple websocket things present)
- Zlib (bun has its own gzip?)
- Http (Nodes built in HTTP, should use Bun's own, right?)
- URL (available in globals)
- Constants (deprecated)
- Querystring (deprecated)
- Punycode (deprecated)
- Console (Core has it)
- How to reuse/contribute to
rescript-webapi
instead of rolling our own bindings. I've intentionally not reused any other existing library because I wanted to start from scratch and follow ReScript v11 idioms as much as possible. But once all of this settles, we need to figure out and share the common denominator withrescript-webapi
and other similar projects to this.
Contributions are very welcome. We're aiming to cover close to 100% of the Bun API surface, which is quite huge task. But, it's definitively possible and the initial large effort pays dividends over time.
If you do want to contribute, please open an issue saying you're starting work on module X. So we don't accidentally double work.
This will be fleshed out in a short while.