# mqttbytes-core-next
[](https://crates.io/crates/mqttbytes-core-next)
[](https://docs.rs/mqttbytes-core-next)
`mqttbytes-core-next` contains shared MQTT packet primitives used by the `rumqttc-next` protocol crates.
## Scope
- Shared `QoS`, topic, ping, and primitive byte helpers.
- Reused by both `rumqttc-v4-next` and `rumqttc-v5-next`.
- Intended mainly for the rumqtt client family and advanced integrations that need low-level MQTT building blocks.
This crate is not a full MQTT client and does not provide networking, event loops, or broker session management.