zig-dom

A Zig-backed DOM implementation.

Install

Bun

bun add zig-dom

npm

npm install zig-dom

Test Setup

Create a Bun preload file:

// preload.ts
import { GlobalRegistrator } from "zig-dom/global-registrator";

GlobalRegistrator.register();

bunfig.toml

[test]
preload = ["./preload.ts"]

CLI

bun test --preload ./preload.ts

Vanilla JS

import { test, expect } from "bun:test";

test("updates the document", () => {
  document.body.innerHTML = "<button>Save</button>";
  expect(document.querySelector("button")?.textContent).toBe("Save");
});

React

import { render, screen } from "@testing-library/react";
import { test, expect } from "bun:test";

test("renders", () => {
  render(<button>Save</button>);
  expect(screen.getByRole("button").textContent).toBe("Save");
});

Benchmarks

Run with:

bun run benchmark:dom

Latest local run: 2026-05-04 21:20:08 UTC on darwin-arm64.

Metric	zig-dom	happy-dom	jsdom	vs happy-dom
Append 10k children	0.89 ms	3.30 ms	8.55 ms	zig-dom is 3.7x faster
Create 10k elements	2.35 ms	3.38 ms	7.30 ms	zig-dom is 1.4x faster
Query .class across 10k nodes	1.58 ms	13.98 ms	18.45 ms	zig-dom is 8.8x faster
Query [attr] across 10k nodes	1.32 ms	7.01 ms	15.06 ms	zig-dom is 5.3x faster
Parse innerHTML	0.44 ms	11.54 ms	25.03 ms	zig-dom is 26.0x faster
Serialize outerHTML	0.13 ms	1.88 ms	2.06 ms	zig-dom is 14.7x faster
Mixed DOM workflow, 10k ops	20.70 ms	76.69 ms	116.29 ms	zig-dom is 3.7x faster
Mutation observer append, 10k nodes	11.01 ms	16.42 ms	36.68 ms	zig-dom is 1.5x faster
React render, 10k rows	48.92 ms	103.81 ms	132.10 ms	zig-dom is 2.1x faster
React update, 10k rows	39.03 ms	39.38 ms	53.39 ms	zig-dom is 1.0x faster
Import time	29.94 ms	68.86 ms	491.57 ms	zig-dom is 2.3x faster