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

# Custom markers

[Custom markers](/application/markers/custom-markers) can be added to graphs and charts to mark important changes. They work similarly to Deploy markers, which let you know when a deployment was made.

There are several ways to send [custom markers](/application/markers/custom-markers), through our UI, [API](/api/markers) and [public endpoint API](/api/public-endpoint/custom-markers).

The Ruby gem also includes a helper class to create custom markers through our public endpoint.

See the example below on how it can be used:

<CodeGroup>
  ```ruby Ruby theme={null}
  Appsignal::CustomMarker.report(
    # The icon shown on the timeline
    :icon => "🎉",
    # The message shown on hover
    :message => "Big event happened!",
    # Any time object or a string with a ISO8601 valid time is accepted
    :created_at => Time.now
  )
  ```
</CodeGroup>

You can call this helper anywhere in your application where an event occurs that needs to be tracked on the graph timeline, like Rake tasks.