# Backtest Demo Favorites

> Tiny demo skill bundled with `simmer backtest --demo`. Buys YES on liquid favorites to exercise the full backtest pipeline offline.

- Skill: `spartanlabsxyz/backtest-demo-favorites` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add spartanlabsxyz/backtest-demo-favorites`
- Raw SKILL.md: https://api.skillmd.com/api/skills/spartanlabsxyz/backtest-demo-favorites/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: DevOps & Infra
- Author: SpartanLabsXyz (https://skillmd.com/u/spartanlabsxyz)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/spartanlabsxyz/backtest-demo-favorites

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# Backtest demo — favorites buyer

This is **not** a real trading strategy. It exists so `simmer backtest --demo`
produces a meaningful report (decisions, trades, settlements, hit_rate, pnl,
baselines) with no network access and no tape download.

Each tick it buys a small fixed amount of YES on the most liquid markets
trading as favorites (YES price in a mid-to-high band), skipping anything it
already holds. Run against the bundled 10-market demo slice, a handful of those
favorites resolve YES (wins) and a handful resolve NO (losses), so the demo
shows a realistic mixed outcome rather than "0 trades, stayed flat".

Entrypoint: `favorites_demo.py` (reads `SIMMER_API_URL` / `SIMMER_API_KEY` from
the replay harness; accepts and ignores `--live` / `--quiet`).