Indie dev builds AI design tool Rivermark with Claude in a month, already monetizing via side gigs
JannVanDam · reddit · 2026-11-13
Reddit user JannVanDam shares how he vibe-coded Rivermark, an AI social-media design tool positioned as a Canva × Claude Design hybrid with an infinite canvas and an always-on agent, in about a month using Claude Opus. Key lessons: early versions failed constantly until he systematically analyzed each session's failures; the backend tracks conversation context and canvas state; he had Claude rebuild a 1:1 replica of Figma's properties panel as an HTML reference; and he swapped underlying models multiple times to get the agent to understand app state. The tool is free (no billing implemented yet) and he already uses it for freelance work.
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