Show HN: Δlchimist – Local-first AI persona engine for the browser (BYOK)

Alchimist is a local-first AI persona engine that runs entirely in the user's browser. It lets people create and interact with AI characters ("personas") without sending data to external servers, since all processing happens client-side. It uses a BYOK ("Bring Your Own Key") model, meaning users supply their own API key (e.g., from OpenAI or Anthropic) to power the AI, rather than relying on a built-in or subscription-based service. This approach prioritizes privacy and user control, but requires some technical comfort to set up. The project appears on Hacker News as a "Show HN" — a post where makers present their work to the HN community for feedback.