Show HN: OpenGravity – A zero-install, BYOK vanilla JS clone of Antigravity

An experimental, lightweight, BYOK (Bring Your Own Key) recreation of the Google Antigravity UI. Open Gravity provides a browser-based, reasoning-enabled IDE with a live xterm.js terminal powered by the Web Container API. It features direct local file system sync and a proactive autonomous agent capable of orchestrating basic software engineering tasks, running shell commands, and editing files in real-time. It’s currently a work-in-progress though. It works for basic coding tasks, but consider this the "Alpha" version.

Built in pure HTML/CSS/JS for maximum speed and zero installation.

I was using Google Antigravity quite intensively for a load of projects I was making. Very quickly, I got hit with rate limits. Google Antigravity has become over the past few months quite infamous for this, and doesnt seem to be improving. I was thinking of switching to a CLI, or a vscode based program instead, but I really love the Antigravity UI. So I went to Google AI Studio, and put in a LOAD of screenshots, and with a load of interesting prompt engineering techniques, gemini 3.1 pro put together a beautiful clone (if I may say so myself). I loved how it looked, so over a couple of days in some free time, I used it to wire together some features, like the file management and agent logic, and here we are! 📸 Examples Autonomous Web Development The agent can proactively initialize projects, install dependencies using pnpm, and build complete applications while you watch.