Show HN: Whiteboard (YC W26) – An open-source IDE for thoughtful software design

Whiteboard is an open-source desktop IDE that enables humans and AI agents to collaborate on software design in a shared workspace, integrating with tools like Claude Code and Codex. The application allows agents to visualize their work on an in-app canvas and is designed to facilitate thoughtful software architecture through guided prompts and interactive review processes. It's optimized for advanced AI models like GPT-6 Luna and Claude Opus 5.5 and is available as a free download for macOS.