Cursor, Erich Gamma, VS Code Forks and the Role of the Eclipse Foundation (redmonk.com)

Cursor’s AI-first editor startup just closed a headline-grabbing Series D — $2.3B at a $29.3B post-money valuation — signalling massive VC conviction in “IDE-as-AI-platform” businesses. Cursor is essentially a polished VS Code fork wrapped with Claude/Sonnet-powered copilots and a developer UX that appeals to teams building LLM-native workflows. That level of financing validates the commercial opportunity in embedding generative models directly into coding surfaces and raises the stakes around who controls those surfaces and their ecosystems. The Eclipse Foundation’s Open VSX registry is now a central piece in that battle: it’s the open, cross-editor marketplace used by VS Code forks (VSCodium, Cursor, Windsurf) and by AWS’s Kiro IDE, which has also backed Eclipse. Microsoft restricts use of the official VS Code Marketplace to its Visual Studio family, forcing forks to rely on Open VSX and prompting debate about extension points, marketplace rules and vendor lock-in. Practically, this affects extension compatibility, discovery, and how third parties integrate LLMs and proprietary services into editors. There’s an ironic historical twist: Erich Gamma — who led the original Eclipse IDE and later Project Monaco/VS Code at Microsoft — sits at the center of both worlds, while Eclipse Foundation’s stewardship could become the open-standards counterweight shaping the future of AI-enabled developer tools.