Terminology

Shared vocabulary for FeatherFly plugin development.

FeatherFly plugin vocabulary — read this before writing hooks.

Term	Meaning
Plugin	A native `.so` shared library loaded by the daemon at startup.
Host	The running FeatherFly daemon. Passes `HostApi` to your `init`.
Hook	A callback your plugin registers during `init`.
Event	A lifecycle hook fired at a fixed point (startup, shutdown, config load).
Config mutation hook	Rewrites raw config YAML bytes before settings are applied (`config.mutate`).
Request hook	Runs before HTTP handlers — `request.intercept` (outer) or `middleware.inject` (inner).
Plugin route	A handler registered with `route!` that serves a new HTTP endpoint.
JSON mutation hook	A hook that receives JSON bytes, may rewrite them, and returns output for HTTP responses.
CloudPanel command hook	A hook that receives CloudPanel operation metadata and CLI args JSON, then continues, rewrites args, or cancels.
Target	What a hook listens to — an event name, config pipeline, route prefix, or JSON target.
Pipeline	Ordered chain of hooks for one target. Each hook sees the previous hook's output.
Mixin	FeatherFly's model for JSON hooks: multiple plugins stack transformations on the same response, like Minecraft mixins layering behavior.
Load order	Alphabetical by `.so` filename in the plugins directory. Determines pipeline order.
Cancel	Lifecycle hooks may call `HookResult::cancel()` to skip remaining handlers for that event.
API version	Integer in `PluginEntry`. Must match `FEATHERFLY_PLUGIN_API_VERSION` or the plugin is skipped.
Action	A panel step object `{ id, label, step }` returned in API responses for follow-up work.