Web Bro

Web Bro

Browser-only workspace agent built with transformer.js.

**Repository:** https://github.com/aeroxy/web-bro

What It Does

• Runs Gemma 4 E2B-it ONNX fully in the browser on WebGPU.
• Lets the user pick a local folder as the workspace with the File System Access API.
• Uses a shallow tool loop for list_dir, search_text, read_file, and write_file.
• Writes directly into the selected workspace, snapshots the previous contents in IndexedDB, and shows a diff with one-click undo.
• Persists chat threads, workspace sessions, settings, and write backups locally only.

Requirements

• Desktop Chromium browser.
• Secure context: HTTPS or localhost.
• WebGPU enabled.
• Enough local bandwidth and disk cache for the first model download. The ONNX runtime and model assets are large.

Scripts

pnpm dev
pnpm build
pnpm preview
pnpm lint
pnpm typecheck
pnpm test
pnpm e2e

`pnpm e2e` expects Playwright browsers to be installed. The default Vitest suite uses mocked workers and does not download the real model.

Architecture

• src/app/store.ts: Zustand vanilla store, persistence wiring, agent loop orchestration.
• src/workers/llm.worker.ts: Gemma model loading, native tool-call prompting via apply_chat_template, streamed answer pass, cancellation.
• src/workers/workspace.worker.ts: directory traversal, file reads, text search, writes, delete-on-undo support.
• src/features/chat and src/features/workspace: UI shell.
• public/_headers and public/_redirects: Cloudflare Pages static deployment defaults.

Notes

• Existing files must be read earlier in the same turn before the agent can overwrite them.
• The current implementation is intentionally Chromium-first and does not ship a non-WebGPU fallback.
• Model artifacts are fetched from Hugging Face on first use and then cached by the browser.