vynn-backtester

# Vynn Backtester

Backtest any trading strategy with natural language. Get Sharpe ratio, returns, drawdown, and full equity curves in seconds.

## What it does

- **Natural language strategies**: Describe your strategy in plain English and Vynn translates it into a runnable backtest
- **Structured strategies**: Power users can pass precise entry/exit rules as JSON
- **Full metrics**: Sharpe ratio, total return, max drawdown, win rate, trade count, and equity curve
- **Multi-ticker**: Backtest across any combination of stocks, ETFs, or indices
- **Strategy comparison**: Compare multiple strategies head-to-head, ranked by Sharpe ratio
- **No infrastructure**: No local data downloads, no dependencies beyond Python stdlib

## Setup

1. Get a free API key at [the-vynn.com](https://the-vynn.com) (10 backtests/month, no credit card)
2. Set `VYNN_API_KEY` in your environment or skill config
3. Run `/backtest "your strategy here"` from any OpenClaw agent

### Quick start

```bash
# Sign up (instant, returns your API key)
curl -X POST https://the-vynn.com/v1/signup -H "Content-Type: application/json" -d '{"email": "you@example.com"}'

# Set the key
export VYNN_API_KEY="vynn_free_..."
```

## Usage examples

### Simple natural language backtest

```
/backtest "RSI mean reversion on AAPL, 2 year lookback"
```

### Momentum strategy

```
/backtest "MACD crossover on SPY with 20/50 EMA filter"
```

### Multi-ticker portfolio

```
/backtest --tickers AAPL,MSFT,GOOGL --strategy "momentum top 3"
```

### Structured entry/exit rules

```
/backtest '{"entries": [{"indicator": "RSI", "op": "<", "value": 30}], "exits": [{"indicator": "RSI", "op": ">", "value": 70}]}' --tickers AAPL
```

### Compare strategies

```python
from plugin import VynnBacktesterPlugin

vynn = VynnBacktesterPlugin()
results = vynn.compare(
    strategies=[
        "RSI mean reversion",
        "MACD crossover",
        "Bollinger band breakout",
    ],
    tickers=["SPY"],
)
for r in results:
    print(f"{r.stra...