Extreme-only prediction markets (90:10+) across 5 chains. Built solo with AI in weeks, not months.
FatTail is purpose-built for extreme probability markets. By focusing exclusively on 90:10+ skew, we create a natural two-sided market: stable carry for the 90% side and explosive convexity for the tail.
| Feature | FatTail | Polymarket | Kalshi |
|---|---|---|---|
| Probability Range | 90:10+ only | Any range | Any range |
| Fee Model | Dynamic vig (0.3–3%) | Flat 2% | Flat 1% |
| Yield Mechanism | Vig distribution to 90% side | None | None |
| Bot API | REST + Python/TS SDKs | CLOB API | Limited |
| Settlement | Admin + Price Feed + Optimistic Oracle | UMA Oracle | Centralized |
Every trade generates a dynamic fee (vig): 0.3% for 90/10 markets, up to 3% for balanced markets. 50% goes to the platform, 50% is distributed pro-rata to yield seekers on the dominant side.
Regulatory-compliant points. No cash exposure. Platform earns vig on every trade.
Direct crypto trading on 5 chains. Platform earns vig + spread.
MoonPay card-to-USDC. Platform earns referral commission.
One builder + Claude Code = full-stack prediction market with 5-chain support, bot API, and Telegram integration.
Foundation
LS-LMSR math engine + 69 unit tests
DB & Auth
Supabase with RLS + K-Point system
Trading
Buy/sell with dynamic vig + safety guards
Oracle
Admin + Price Feed + Optimistic dispute resolution
Multi-chain
Solana + Base + Arbitrum + Optimism + Polygon
Telegram Bot
Balance, positions, price alerts via grammY
Bot API
REST API + Python/TypeScript SDKs
Landing + Docs
Astro 5 landing, Starlight docs, multi-subdomain deploy
Claude Code wasn't just an autocomplete tool — it was the architect, debugger, and reviewer. Every phase was planned, implemented, tested, and documented through AI-assisted development, proving that a solo builder can ship production-grade DeFi infrastructure.
The technology is replicable. The moat is in the network and positioning.
21K DeFi subscribers trust the builder. That distribution channel can't be replicated by adding a feature.
Once yield seeker ↔ tail hunter liquidity forms, late entrants face cold start on both sides.
Traders who build strategies on FatTail SDK have switching costs. First ecosystem wins.
“Extreme probability = FatTail” — category creators have first-mover advantage.
At TVL $10M with 10% daily turnover, a $10K position on the 90% side earns ~$1,566/year (APR ~15.7%).
Real APR is ~70-80% of above after market expiry and reinvestment cycles. Auto-compound is built in.
Solo builder + DeFi YouTube creator (21K subscribers), vibe-coded with Claude Code.