> For the complete documentation index, see [llms.txt](https://overmindjs.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://overmindjs.org/master-1/api-1/events.md).

# events

Overmind emits events during execution of actions and similar. It can be beneficial to listen to these events for analytics or maybe you want to create a custom debugging experience. The following events can be listened to by adding a listener to the eventHub:

```typescript
overmind.eventHub.on('action:start', (execution) => {})
overmind.eventHub.on('action:end', (execution) => {})
overmind.eventHub.on('operator:start', (execution) => {})
overmind.eventHub.on('operator:end', (execution) => {})
overmind.eventHub.on('operator:async', (execution) => {})
overmind.eventHub.on('mutations', (executionAndMutations) => {})
overmind.eventHub.on('derived', (derived) => {})
overmind.eventHub.on('derived:dirty', (derivedPathAndFlush) => {})

// Only during development
overmind.eventHub.on('effect', (effectDetails) => {})
overmind.eventHub.on('getter', (getterDetails) => {})
overmind.eventHub.on('component:add', (componentDetails) => {})
overmind.eventHub.on('component:update', (componentDetails) => {})
overmind.eventHub.on('component:remove', (componentDetails) => {})
```


---

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