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

# Midaz and plugin compatibility

> Which capabilities the unified Ledger serves as modules, and which ones run as separate plugins.

## Midaz application v4

***

| Capability | Runs as | API surface |
| :- | :- | :- |
| CRM | Unified Ledger module | `/v2` only |
| Fees | Unified Ledger module | `/v2` only |
| Pix and Bank Transfer | Separate plugins | See each plugin's API guide |

In Midaz application v4, the unified Ledger contains CRM and Fees as modules. Use their `/v2` API through the Ledger. They are not separate services, ports, or plugins. The `/v1` compatibility surface does not run Fees or Tracer.

Before Midaz v4, Fees ran as its own service. Its earlier releases do not define Midaz v4 compatibility.

## Upgrade order

***

Upgrade Midaz before you upgrade its plugins. Plugins call the Midaz APIs, so a plugin that is newer than Midaz can call an API that Midaz does not serve yet.

To install or upgrade Midaz, see the [Midaz chart README](https://github.com/LerianStudio/helm/tree/main/charts/midaz).


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