WASM SDK

The conduyt-wasm package compiles the Rust protocol core to WebAssembly. It gives you CRC8, COBS framing, and wire encode/decode - the same implementation used by the native Rust SDK - running in the browser or Node.js.

When to use

Use conduyt-wasm when you want to:

• Build a browser-based hardware control interface (pair with WebSerial or WebBluetooth)
• Guarantee byte-level conformance with the native SDKs
• Avoid reimplementing the protocol in JavaScript
• Build an edge/serverless app where WASM runs natively (Cloudflare Workers, Deno, etc.)

If you're building a Node.js app, you can use either conduyt-wasm or the pure-JS conduyt-js SDK - both implement the same protocol. The JS SDK includes higher-level features (device management, transports, modules) while the WASM module provides just the protocol primitives.

Install

npm install conduyt-wasm

Initialize

The WASM module must be initialized before use. This loads the .wasm binary.

Browser

import init, * as conduyt from 'conduyt-wasm';
await init(); // fetches and instantiates the WASM module

Node.js

import init, * as conduyt from 'conduyt-wasm';
import { readFile } from 'fs/promises';

const wasmBytes = await readFile('node_modules/conduyt-wasm/conduyt_wasm_bg.wasm');
await init(wasmBytes);

Encode and decode packets

const CMD = conduyt.getCMD();

// Build a PIN_WRITE command: pin 13, value 1
const pkt = conduyt.makePacket(CMD.PIN_WRITE, 0, new Uint8Array([13, 1, 0]));

// Encode to wire format (8-byte header + payload + CRC8)
const wire = conduyt.wireEncode(pkt);

// COBS-encode for serial transport (eliminates 0x00 bytes)
const frame = conduyt.cobsEncode(wire);

// Send over WebSerial...
await port.writable.getWriter().write(
  new Uint8Array([...frame, 0x00]) // add 0x00 delimiter
);

Decode incoming packets

// Receive bytes from serial, accumulate until 0x00 delimiter
const cobsFrame = receivedBytes; // everything before the 0x00

const decoded = conduyt.cobsDecode(cobsFrame);
if (decoded) {
  const pkt = conduyt.wireDecode(decoded);
  console.log('Type:', pkt.type, 'Seq:', pkt.seq, 'Payload:', pkt.payload);
}

Find packets in a stream

// wireFindPacket scans a buffer for the first valid packet
const result = conduyt.wireFindPacket(buffer);
if (result) {
  const [packet, bytesConsumed] = result;
  // process packet, advance buffer by bytesConsumed
}

Constants

const CMD = conduyt.getCMD();  // { PING: 0x01, HELLO: 0x02, PIN_MODE: 0x10, ... }
const EVT = conduyt.getEVT();  // { PONG: 0x80, HELLO_RESP: 0x81, ACK: 0x82, ... }
const ERR = conduyt.getERR();  // { UNKNOWN_TYPE: 0x01, CRC_MISMATCH: 0x02, ... }

conduyt.errName(0x04);         // "INVALID_PIN"
conduyt.PROTOCOL_VERSION();    // 1
conduyt.HEADER_SIZE();         // 8

WebSerial Example

Complete browser example - connect to a CONDUYT board, send HELLO, and blink an LED:

import init, * as conduyt from 'conduyt-wasm';
await init();

const CMD = conduyt.getCMD();
const EVT = conduyt.getEVT();
let seq = 0;

// Request serial port (requires user gesture)
const port = await navigator.serial.requestPort();
await port.open({ baudRate: 115200 });

function sendPacket(type, payload = new Uint8Array(0)) {
  const pkt = conduyt.makePacket(type, seq++, payload);
  const wire = conduyt.wireEncode(pkt);
  const frame = conduyt.cobsEncode(wire);
  const writer = port.writable.getWriter();
  writer.write(new Uint8Array([...frame, 0x00]));
  writer.releaseLock();
}

// Send HELLO
sendPacket(CMD.HELLO);

// Set pin 13 to output
sendPacket(CMD.PIN_MODE, new Uint8Array([13, 0x01]));

// Toggle LED
sendPacket(CMD.PIN_WRITE, new Uint8Array([13, 1, 0]));

Size

Full API Reference

See the conduyt-wasm README for the complete function reference table.