Rotunda

Rotunda is a browser forked from Firefox, purpose-built for agent automation with an emphasis on operating honestly within fingerprinting detection systems. Unlike traditional browser automation solutions that often trigger bot detection mechanisms, Rotunda is engineered so that agents running locally on a user's network can interact with the web in a manner closely resembling human behavior. This approach is aimed at minimizing captchas, login failures, and session blocks that typically hinder automated workflows.

The tool distinguishes itself by eschewing common stealth tactics such as spoofing hardware or lying about the underlying platform. Instead, Rotunda reports genuine hardware characteristics—such as GPU, audio drivers, and platform—while only varying attributes that humans routinely change, like installed fonts, browser extensions, screen size, and locale. This strategy is designed to prevent detection by modern fingerprinting techniques, which can probe thousands of browser and hardware surfaces to identify automation.

Rotunda implements human-like interaction patterns using custom machine learning models trained on real user mouse movements and keystroke behaviors. Automated agents controlled through Rotunda exhibit natural mouse path predictions, including overshoots and course corrections, as well as keystroke cadences with occasional errors, making their actions less distinguishable from those of human users. The browser is driven via the Playwright automation library, but instead of using the conventional Chrome DevTools Protocol (CDP), it leverages Firefox’s Juggler protocol. This choice is intended to keep automation commands isolated from the page context, reducing the risk that sites can detect agent-driven activity at the protocol layer.

Rotunda is designed for use on personal devices such as laptops and home servers, operating on residential IP addresses rather than datacenter infrastructure. This local-first approach aligns with the needs of modern agent frameworks and local automation loops, allowing agents to operate as if they are simply another tab in a user's regular browsing session. 0 license.