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Henk van Ess (solo)

Built with Opus 4.6: a Claude Code hackathon

Gym memberships, app terms, pet adoptions, sweepstakes — the things you sign with a shrug. They weren't written with one. FlipSide treats a $2 coupon with the same seriousness as a $500,000 corporate lease. Existing legal tech targets lawyers. Try finding one that handles gym memberships or sweepstakes. Upload any document or pick from 14 samples. Flip cards: the front shows what the drafter wants you to feel. Flip it to see what an expert catches. Risk scores, trick types, dollar figures. Why Opus 4.6? Haiku builds cards fast and parallel. The verdict needs Opus: cross-clause reasoning connecting a liability waiver on page 2 to an arbitration clause on page 8, and theory of mind that reconstructs drafter intent. Millions sign one-sided documents without seeing the other side. Now they can. 0% human code. 14,000+ lines built through conversation with Claude Code. 116 commits. 6 days.

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