# Migration Guide from 0.4.x to v0.5.x

## Crate configuration changes

To prevent ambiguity between configurations, we had to change the naming format of configuration
keys. Before, we used `{prefix}_{key}`, which meant that esp-hal and esp-hal-* configuration keys
were impossible to tell apart. To fix this issue, we are changing the separator from one underscore
character to `_CONFIG_`. This also means that users will have to change their `config.toml`
configurations to match the new format.

```diff
 [env]
-ESP_IEEE802154_RX_QUEUE_SIZE = "50"
+ESP_IEEE802154_CONFIG_RX_QUEUE_SIZE = "50"
```