> [!abstract] An integration pattern that offloads large event payloads to external storage, passing only a reference (claim check) in the event itself.
## How It Works
1. At publish time, store additional data in a separate location (cache, API, S3)
2. Include an identifier/reference in the event payload
3. Consumers retrieve the data if needed using the identifier
## Benefits
- Keeps events lightweight
- Prevents overloading core services with callbacks
- Consumers only fetch data they actually need
## When to Use
- Large payloads that would bloat events
- Data that only some consumers need
- Avoiding callback storms from [[Notification Events vs Fat Events|thin events]]
## Sources
[[x_Sources/Videos/Video - Build An Event Driven System - NDC Oslo 2024|Build An Event Driven System - James Eastham (NDC Oslo 2024)]]