swc VS sucrase

First, we switched the default compiler for new projects from Babel to SWC (Speedy Web Compiler). SWC is dramatically faster than Babel and requires zero configuration. We’ll continue to support Babel in any project currently using it.

SWC

As the reference explains “**SWC** (Speedy Web Compiler) is an extensible Rust-based platform that can be used for both compilation and bundling. Using SWC with Nest CLI is a great and simple way to significantly speed up your development process.”

This is specifically about breaking the myth that performing expensive self-contained operations (e.g, parsing GraphQL) in a native extension (C, Rust, etc.) is always faster than the interpreted language.

The JS ecosystem has the same problem, people think rewriting everything in Rust will be a magic fix. In practice, there's always the problem highlighted in the post (transitioning is expensive, causes optimization bailouts), as well as the cost of actually getting the results back into Node-land. This is why SWC abandoned the JS API for writing plugins - constantly bouncing back and forth while traversing AST nodes was even slower than Babel (e.g https://github.com/swc-project/swc/issues/1392#issuecomment-...)

Why Speedy Web Compiler ?

FTA is a TypeScript static analysis tool built on the speedy foundations of swc. FTA is fast; capable of analyzing more than 150 files per second on typical hardware, it offers a powerful addition to your code quality toolkit.

Very cool! I'm curious, is this intended for dev tooling?

For example, I could see this (or something similar) being useful as the engine for a typescript language server that would be faster than the standard one

But if it's not aimed at 1:1 with tsc, would it be intended more for something like swc[1]?

Or what would you expect people to use this for, besides just being a cool project to learn from?

[1] https://github.com/swc-project/swc

This is... good news, but I still cannot fathom using the default Typescript compiler for regular development. Seriously, leave the type-checking to your IDE and CICD chain, and switch to using tsx (https://www.npmjs.com/package/tsx) or swc (https://swc.rs/) and you will _immediately_ notice the difference in speed and productivity.

Thanks. As for the code compilation, that can be tested and seen in https://sucrase.io/

The demo page is only to show how we can transpile JSX in browsers.

Thanks u/OutlandishnessKey953, the playground built with React, Docusaurus(https://docusaurus.io/), CodeMirror(https://codemirror.net/), Sucrase(https://sucrase.io/), etc.

Hi, Sucrase author here.

To be clear, the benchmark in the README does not allow JIT warm-up. The Sucrase numbers would be better if it did. From testing just now (add `warmUp: true` to `benchmarkJest`), Sucrase is a little over 3x faster than swc if you allow warm-up, but it seemed unfair to disregard warm-up for the comparison in the README.

It's certainly fair to debate whether 360k lines of code is a realistic codebase size for the benchmark; the higher-scale the test case, the better Sucrase looks.

> worse it disables esbuild and swc's multi-threading

At some point I'm hoping to update the README benchmark to run all tools in parallel, which should be more convincing despite the added variability: https://github.com/alangpierce/sucrase/issues/730 . In an ideal environment, the results are pretty much the same as a per-core benchmark, but I do expect that Node's parallelism overhead and the JIT warm-up cost across many cores would make Sucrase less competitive than the current numbers.

First, npm i -D sucrase to install sucrase. Now you can do node -r sucrase/register ./index.ts to run TypeScript code directly with Node.

As you might know there are a lot of Javascript bundlers out there, such as webpack, sucrase, parcel, rollup and etc. Bear in mind, not because they have thousands of stars on Github that means they're the best. sometimes new libs are as good as the popular ones but they're still building up their image/popularity in the community. what I bring today is a not sooooo, popular JS bundler called esbuild.

Sucrase JS was 2x the speed of esBuild and 50% faster than SWC last I checked.

Webpack does way more than esbuild, including running a typechecking compiler instead of just transpiling, running compilers able to downlevel emit to ES5 and providing a deep plugin architecture allowing you to hook into any bit you like. But yes, it hasn't been designed with speed in mind - it has been designed with maximum extensibility instead. Its the same reason why Babel is slow compared to sucrase (written in JS, currently faster than SWC and esbuild but doing somewhat less - https://github.com/alangpierce/sucrase)

tsc has in fact been designed with speed in mind (I've been following the project since before it ended up on GitHub). Going beyond 1 order of magnitude performance improvement is highly unlikely.