Bug0 is a hosted AI QA service that pairs agentic browser testing with human-verified oversight — either self-serve (Studio, from $250/month) or fully managed with a dedicated QA engineer (from $2,500/month). It's built on top of Passmark, its own open-source testing engine, so teams that want the underlying AI-driven test automation without the managed service or subscription can use that engine directly.
FAQ
Is there a free, open-source alternative to Bug0?
Yes. Passmark is the source-available (FSL-1.1-ALv2) engine Bug0 itself is built on, and you can run it directly without Bug0's managed service.
What's the best open-source alternative to Bug0?
Passmark gives you the same plain-English, auto-healing test generation without Bug0's per-month managed QA pricing.
What are the top open-source alternatives to Bug0?
Browse all open-source alternatives to Playwright for more end-to-end testing tools, or explore the full Developer Tools category.