---
title: 'CHR0013: Reactor cannot combine EventStore with explicit event sequence'
---

## Rule Description

A reactor that declares `[EventStore("...")]` must use implicit inbox routing. It cannot also define an explicit event sequence.

## Severity

Error

## Example

### Violation

```csharp
using Cratis.Chronicle.Events;
using Cratis.Chronicle.Reactors;

[EventStore("identity-service")]
[Reactor(eventSequence: "custom-sequence")]
public class UserSyncReactor : IReactor
{
}
```

### Fix

```csharp
using Cratis.Chronicle.Events;
using Cratis.Chronicle.Reactors;

[EventStore("identity-service")]
[Reactor]
public class UserSyncReactor : IReactor
{
}
```

## Why This Rule Exists

`[EventStore]` on a reactor is intended to drive outbox-to-inbox routing. Combining it with explicit event sequence configuration creates ambiguous routing intent.

## Related Rules

- [CHR0014](/chronicle/code-analysis/chr0014/): Reducer cannot combine EventStore with explicit event sequence