LEMMAIR/justune

Justune is in its earliest experimental stages with only 3 stars and 2 forks. While the concept of a browser-native agent runtime is interesting for privacy and reduced compute costs, it currently functions as a prototype/demo rather than a defensible tool. It faces immense competition from established players like StackBlitz (who provide the underlying WebContainer technology likely used here) and Replit. Furthermore, the frontier risk is high because labs like OpenAI and Google are actively developing 'Computer Use' and 'Operator' capabilities that will likely be integrated directly into browsers or operating systems, making a third-party browser-based runtime redundant. The defensibility is currently rated a 2 because it lacks a novel technical moat or community traction, serving more as a reference implementation for using WebContainers with agents than a standalone product. Displacement is likely within 6 months as larger IDE and agent frameworks (like OpenDevin or Plandex) incorporate similar local-first browser capabilities.