# External Components

Below is a non-complete list of stream components that are maintained by other projects.

[Contributions](https://github.com/akka/alpakka/blob/master/CONTRIBUTING.md) are very welcome.
[Creating an issue](https://github.com/akka/alpakka/issues) for discussion is a good first step for such contributions.

## Buffers

[Persistent & Broadcast Buffer implemented using Chronicle Queue](https://squbs.readthedocs.io/en/latest/persistent-buffer/)

## Resilience

[Stream Circuit Breaker](https://squbs.readthedocs.io/en/latest/circuitbreaker/)

[Stream Deduplicate](https://squbs.readthedocs.io/en/latest/deduplicate/)

[Stream Bounded Ordering](https://squbs.readthedocs.io/en/latest/flow-ordering/)

[Stream Retry](https://squbs.readthedocs.io/en/latest/flow-retry/)

[Timeout Flow](https://squbs.readthedocs.io/en/latest/flow-timeout/)

## Metrics

[Stream Materialization Metrics](https://squbs.readthedocs.io/en/latest/materialization-metrics-collector/)