cheenar / Winx.js

Lightweight, JavaScript Runtime 🦋; Built on V8 🚅; Inspired by Bun.sh 💛

🦋 Winx.js

• Lightweight, JavaScript Runtime
• Built on battle-tested (presumably!) V8 JavaScript Engine
• Building towards JNI support

Configuration

You can define a Winx.toml file in the same directory as executing the winx binary. You are able to configure any V8 Flag by default.

[v8]
max-heap-size = 2048
jitless = true
gc-experiment-less-compaction = true
expose-wasm = false

[winx]
polyfills_file = "./polyfills/Winx.js"
modules_folder = "./examples/"

[winx] Config

• polyfills_file - Location to load the "polyfills" to support features such as console.log.

API

All Winx API methods are available under the Winx global object.

Filesystem

The Winx.fs object provides bindings for accessing the file system. There are two ways to use the filesystem, a "blind" read or write, in which the totality of the file content is handled, or via the FileHandle system.

Winx.fs.blind_file_write("my_file.txt", "Hello Winx!");
Winx.console.log(Winx.fs.blind_file_read("my_file.txt")); // Hello Winx!

With the FileHandle API, you are able to open files in different modes. Currently, single access modes are allowed i.e. Append(a), Write(w), or Read(r).

let file_handle = Winx.fs.open("my_file.txt", "w");
file_handle.write("Hello Winx!");
file_handle.close();

Winx.console.log(Winx.fs.blind_file_read("my_file.txt")); // Hello Winx!

OS

The Winx.os object provides bindings for operating system related processes. Primarily, this is exposing test functions from libuv.

Winx.console.log(Winx.os.get_free_memory()) // 16 Gb
Winx.console.log(Winx.os.get_total_memory()) // 64 Gb

Winx.console.log("What's your name?: ")
let input = Winx.os.stdin();
Winx.console.log(`Hello ${input}`)

Console

The Winx.console object provides bindings for standard console output functions.

Winx.console.log("Hello World!");
Winx.console.debug("Hello World!");

Node & Web API Compatibility

In Winx.js, there are some "polyfills" that provide Node and Web-like APIs for cross-runtime compatiblity. Initially, focus is spent on getting Winx's capabilities up to par with similar runtimes, and compatibility will follow. For performance testing, some examples are duplicated and implemented in Node.js or Bun.sh compatible APIs.

The polyfills are now generated via a make-shift bundler. The bundler does a naive sweep of the Winx.js.template and generates a bundled file. There is no intelligent parsing that generates the file, so it's restricted to only whole file composition. In the future, I want to make it parse the file and insert the imports as needed.