Daniel Park

v0 generated React code but users had to copy-paste it into their own projects to see the result. The generate-copy-paste-preview loop took 90+ seconds per iteration, and 52% of users abandoned after their first generation because they couldn't evaluate the output quickly.

Built an in-browser sandboxed preview engine that renders generated React components in real-time as the AI streams tokens. Used React Server Components with edge-rendered iframes and implemented optimistic UI updates that show partial renders. Added hot-module replacement so edits reflect instantly.

Time from generation to visual preview dropped from 90s to under 3s. First-session retention jumped from 48% to 73%. Users averaged 6.2 iterations per session vs. 1.8 previously. v0 monthly active users grew 4x in the quarter after launch.

Notion blocks experienced merge conflicts when 5+ users edited the same page simultaneously, resulting in lost edits and user-visible glitches.

Implemented a CRDT-based conflict resolution layer for block operations. Built operational transformation for rich text within blocks and a presence-aware cursor system.

Concurrent edit conflicts dropped 94%. Pages with 20+ simultaneous editors remained smooth. Feature enabled Notion to land 3 enterprise deals that required real-time co-editing guarantees.