Whiteboard lets your coding agent draw what it just did
Reading agent output is now the bottleneck. The agent writes the code in four minutes and you spend forty figuring out whether the shape of it is right. Whiteboard, out of YC W26 and MIT licensed, takes a swing at exactly that gap: a local desktop canvas that humans and coding agents share, with an SDK that lets the agent draw on it.
So the agent doesn't just hand you a diff. It draws the diagram — the flow, the boxes, what calls what — describing the work it did, and you look at a picture instead of reconstructing one in your head from 600 changed lines. Click any part of the drawing and you land on the code behind it. Navigate with VSCode keybindings, LSP included. It also logs decisions, so the agent's own reasoning trace is something you can query and see laid out rather than scroll back through.
The piece I'd actually install it for is the semantic diff viewer. Written in Rust, AST-aware, so it strips the noise — reformatting, moved blocks, renames that touch 200 lines and change nothing — and summarizes what actually shifted. Anyone who has reviewed a large agent-generated PR knows the review time is mostly spent separating the real change from the churn around it. That is a mechanical problem and an AST can solve it.
354 stars, hit the Hacker News front page at 148 points, runs entirely locally, Claude Code integration. There's a hosted team version planned, and they've committed that self-hosting stays available. The bet underneath the whole thing is that design and understanding become the scarce goods once generating code is free. That bet is looking increasingly safe.
https://github.com/devdotfast/whiteboard — https://whiteboard.dev.fast/
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So the agent doesn't just hand you a diff. It draws the diagram — the flow, the boxes, what calls what — describing the work it did, and you look at a picture instead of reconstructing one in your head from 600 changed lines. Click any part of the drawing and you land on the code behind it. Navigate with VSCode keybindings, LSP included. It also logs decisions, so the agent's own reasoning trace is something you can query and see laid out rather than scroll back through.
The piece I'd actually install it for is the semantic diff viewer. Written in Rust, AST-aware, so it strips the noise — reformatting, moved blocks, renames that touch 200 lines and change nothing — and summarizes what actually shifted. Anyone who has reviewed a large agent-generated PR knows the review time is mostly spent separating the real change from the churn around it. That is a mechanical problem and an AST can solve it.
354 stars, hit the Hacker News front page at 148 points, runs entirely locally, Claude Code integration. There's a hosted team version planned, and they've committed that self-hosting stays available. The bet underneath the whole thing is that design and understanding become the scarce goods once generating code is free. That bet is looking increasingly safe.
https://github.com/devdotfast/whiteboard — https://whiteboard.dev.fast/
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