> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nanoforge.eu/llms.txt
> Use this file to discover all available pages before exploring further.

# BaseComponentSystemLibrary class

> Abstract base class for component-system (ECS) libraries.

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# BaseComponentSystemLibrary

## Summary

Abstract base class for component-system (ECS) libraries.

## Signature

```typescript theme={null}
declare abstract class BaseComponentSystemLibrary extends Library implements IComponentSystemLibrary 
```

## Remarks

Extend this class (or the higher-level `AbstractECSLibrary`) to implement a custom ECS back-end and register it with `NanoforgeApplication.useComponentSystem`. The built-in implementations are `ECSClientLibrary` and `ECSServerLibrary`.