---
id: "P:cAlgo.API.OptimizationSettings.UseCustomFitness"
kind: "property"
type: "T:cAlgo.API.OptimizationSettings"
url: "https://help.ctrader.com/ctrader-algo/references/Plugin/Optimization/OptimizationSettings/UseCustomFitness/"
---

> Documentation index for agents: https://help.ctrader.com/ctrader-algo/llms.txt · machine index: https://help.ctrader.com/ctrader-algo/api.json

# OptimizationSettings.UseCustomFitness

Member of [OptimizationSettings](https://help.ctrader.com/ctrader-algo/references/Plugin/Optimization/OptimizationSettings/index.md).

## UseCustomFitness

Gets a value indicating whether to use the cBot's custom `GetFitness` instead of [`OptimizationSettings.Criteria`](https://help.ctrader.com/ctrader-algo/references/Plugin/Optimization/OptimizationSettings/Criteria/index.md).

Environments: Desktop supported · CLI not supported · Cloud not supported.

- CLI: Available to plugins only, and plugins cannot run in the CLI.
- Cloud: Available to plugins only, and plugins cannot run in the cloud.

C#:

```csharp
public bool UseCustomFitness {get; set;}
```

Python:

```python
optimizationSettings.UseCustomFitness: bool
```

### Returns

`bool` — 

Available since cAlgo.API 5.9.

### Examples

C#:

```csharp
var settings = new OptimizationSettings(new DateTime(2025, 1, 1), new DateTime(2025, 3, 1), 10000, Array.Empty<OptimizationCriterion>())
{
    UseCustomFitness = true
};
Print("Use cBot GetFitness: {0}", settings.UseCustomFitness);
```

Python:

```python
from System import DateTime
settings = OptimizationSettings(DateTime(2025, 1, 1), DateTime(2025, 3, 1), 10000, [])
settings.UseCustomFitness = True
api.Print(f"Use cBot GetFitness: {settings.UseCustomFitness}")
```