PyDevices Workbench

A MicroPython IDE for Web and Mobile — work with a built-in device simulator or a real board, in the same browser tab.

Live at https://pydevices.github.io/workbench/.

• Simulator: a MicroPython WebAssembly virtual device runs entirely in your browser — no hardware needed.
• Real boards: connect over USB (Web Serial / WebUSB), Bluetooth, or WebREPL. File manager, package installer (mip), and REPL terminal all work the same on every device.
• Editor tooling: CodeMirror with ruff linting/formatting, .mpy cross-compilation, and disassembly — all in-browser.

Part of the PyDevices project: displays, widgets, and graphics for MicroPython.

Built on ViperIDE

Workbench is a fork of ViperIDE by Volodymyr Shymanskyy (MIT license). If you find this useful, please star ViperIDE too — the connectivity, file manager, and editor tooling come from there. Fork policy: PyDevices-specific code lives in new files, diffs to upstream files stay minimal, and generic improvements are sent upstream.

What this fork changes:

• The virtual device is the PyDevices MicroPython WASM build (lvgl, pdwidgets, pygraphics and palettes built in; displaydev, board_config and the rest of pydevices-desktop install from mip at boot), reached from its own toolbar button alongside USB/Bluetooth/WebREPL. It gets a real display stage — resolution and shape presets including round watch faces, live resize, audio, pointer and keyboard input — and boots with example programs for each of those libraries already in its file tree.
• PyDevices branding; no analytics (the Amplitude tracking from upstream is removed).

Development

npm install
python3 build.py --skip-tests   # full build (lint/test skipped) into build/
npm run start                   # watch server at http://localhost:10001

python3 build.py --skip-tests produces the deployable site in build/, including the MicroPython WASM assets (micropython.wasm, the mpy-cross-*.wasm binaries, ruff_wasm_bg.wasm) that the dev server needs to serve the simulator, .mpy compile and lint. --prepare on its own stops before that step — it only vendors dependencies (npm install, python-minifier, the virtual filesystem tarballs) so tools like npm test have what they need without a full build. npm run start reuses whatever is already in build/, so run the full build first (or after pulling changes that touch assets). Plain python3 build.py (no flags) also runs lint and tests before building. CI deploys main to GitHub Pages.

Testing

npm test              # protocol-level suite (test/) - no browser, no hardware
npm run test:browser  # browser-level suite (test/browser/) - drives the built app

npm test exercises src/rawmode.js, src/transports/ and src/package_mgr.js directly against the stock MicroPython WASM VM; point it at real hardware with VIPER_TEST_TARGET (see test/README.md). It never touches the PyDevices runtime. npm run test:browser does: it builds on the same build/ output CI deploys and drives it with Playwright — connecting the simulator, running every example, resizing, resetting, installing a package — so it is what catches PyDevices-runtime regressions the protocol suite can't see. Run python3 build.py --skip-tests first if build/ is stale.

Releases

• Plain vX.Y.Z tags (e.g. v1.2.0) release the app itself: a GitHub Release is created with the built build/ bundle attached as a zip.
• mcp-v* tags release only the MCP tool's npm artifact, from mcp/.
• The inherited v0.5.x–v0.6.x tags predate the fork and are upstream ViperIDE release history, not Workbench releases.

Support

• Issues: https://github.com/PyDevices/workbench/issues (just enabled).
• Browsers: board connectivity (Web Serial / WebUSB / Bluetooth) requires a Chromium-based browser (Chrome, Edge, Opera, Brave, etc.) — not available on Safari or iOS. The simulator has no such requirement and works in any modern browser.

License

MIT, same as ViperIDE.