Indie dev vibe-coded an AI design tool with Claude Opus 5.5 in one month
JannVanDam · reddit · 2026-11-13
An indie developer shares Rivermark (rivermark.ai), a Canva-meets-Claude-Design app built by vibe coding with Claude Opus 5.5: an infinite canvas plus an always-on agent that watches what you do. Early versions failed badly; he iterated by analyzing failures after each session. Technically, he built a canvas plus a backend keeping conversation context and canvas state, had Claude rebuild a 1:1 replica of Figma's properties panel as a reference, and switched underlying models repeatedly to get the agent to understand the canvas. No billing yet — free to try.
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