Create and run a backtest

Sign in to MesoSim. Check Accounts and Access for the available plans and Service Status for the available data period.

Start with the AI Editor

Under Strategies, open New Run → AI Editor, or open the AI Editor directly. This opens the Job Editor with an AI Assistant to help develop your strategy.

Describe the instrument, backtest period, and entry, adjustment, and exit rules you want to test. Answer the assistant's questions, then review the resulting draft in the editor. You can refine it with the assistant or edit the Strategy Definition directly.

For example, start with: “Help me create an SPX options backtest. Ask me about the structure, entry schedule, position size, and exit rules before drafting the strategy.”

Simple Run

Simple Run provides a form for basic structure and exit settings. Add or edit the option legs and inspect the risk graph as you build the position.

A four-leg SPX 0DTE iron condor in Simple Run, with its risk graph and leg settings.

Templated Run

Choose Strategies → New Run → Templated to start from a saved or built-in template. Select the template, symbol, period, and starting cash.

A templated GeneticRhino run configured for SPX over 2025 with $250,000 starting cash.

Validate and submit

1. Review the Strategy Definition in the Job Editor. Check the symbol, backtest dates, starting cash, structure, position size, and entry, adjustment, and exit rules.
2. Select Validate. Resolve the reported field, expression or schedule errors. Use the Strategy Definition Reference and the variables shown by the editor.
3. Select Run job when the strategy is ready.
4. Open Backtests to follow the run and select it to inspect the result.

Validation does not execute the full historical simulation. A run can still fail because data is unavailable or an expression cannot be evaluated at a later simulation step.

Inspect the risk graph at the first entry before submitting the strategy.

Run states and recovery

A submitted run progresses from Created to Started, then Finished or Failed. If submission is rejected, read the error before retrying. If a run fails, inspect its failure message and available events, correct the definition and submit a new run.

Iterate with Clone

Cloning is the main way to iterate on a strategy. Start from an existing backtest and change one thing at a time so you can see how that change affects the results.

1. Open the backtest's Overview tab and select Clone to open a copy of its Strategy Definition in the editor.
2. Change one setting or rule, such as the entry time or profit target. Keep the backtest period and other settings the same for a comparable run.
3. Select Validate, resolve any errors, and select Run job.
4. Compare the new backtest results with the original before deciding what to change next.

Repeat this cycle for each idea you want to test. Use Save as template in the Overview menu when you want to keep a strategy as a reusable starting point.

For more strategy ideas, explore the Strategy Library and the Deltaray blog.