Parameter Sweeps

Parameter sweeps let you test a strategy across many parameter combinations, markets, and timeframes simultaneously. This is the Local Backtester's most powerful feature.

What Is a Parameter Sweep?

Instead of manually changing parameters and running backtests one at a time, a sweep automatically:

1. Generates all combinations of your parameter ranges
2. Runs each combination against your selected markets
3. Collects and ranks results by performance
4. Presents ranked comparison tables

For example, if your strategy has two parameters — fast_period (10 to 50, step 10) and slow_period (50 to 200, step 50) — that's 5 x 4 = 20 combinations tested automatically.

Setting Up a Sweep

1. Navigate to the Sweep tab
2. Select your markets:
   • Exchanges — One or more exchanges
   • Symbols — One or more trading pairs
   • Bars — One or more timeframes
3. Paste your Rune Script strategy
4. Define parameter ranges:
   • From — Start value
   • To — End value
   • Step — Increment between values
5. Click Preview to see the total combinations
6. Click Run Sweep to start

Sweep Preview

Before running, the preview shows:

• Total combinations — How many backtests will run
• Markets ready — Which datasets are available locally
• Markets missing — Which datasets need to be downloaded first
• Runtime tier — Estimated complexity (small, medium, large, extreme)
• Recommended workers — Optimal parallelism for your machine

During a Sweep

While a sweep is running, you'll see:

• Progress bar — Percentage of combinations completed
• Live counters — Completed, errors, and total combinations
• Cancel button — Stop the sweep at any time

Completed results are saved even if you cancel early.

Sweep Results

Results are displayed in a table with columns for each parameter value and performance metric. You can:

• Switch ranking — Two tabs re-rank the table by PnL % or ROI ($)
• View details — Click a row to see the full backtest results for that combination
• Compare across markets — See how the same parameters perform on different symbols

Configuration Ranges

In addition to strategy parameters, you can also sweep the exit configuration:

• Take profit % and Stop loss % — Sweep as From/To/Step ranges, either unified or as separate Long/Short TP and SL ranges

Initial capital, commission rate, slippage, and fee discount are fixed single values that apply to every combination in the sweep — they can't be swept as ranges.

Tips

• Start small — Test with 2-3 parameter values first to verify your strategy works
• Use logical ranges — Don't sweep from 1 to 1000; use ranges that make sense for your indicator
• Watch for overfitting — The best parameters on historical data may not work in live trading
• Test across markets — Parameters that work on multiple symbols are more robust
• Check nearby parameters — If optimal is fast=20, check that fast=18 and fast=22 also perform well (parameter stability)