How would you design a plugin or extensibility system in Go using interfaces?
Define a core Plugin interface, register implementations in a map, and use functional options for configuration. For runtime plugins consider Go's plugin package, though many teams prefer gRPC-based extension points.
Compile-time plugin registry
Design trade-offs
Compile-time plugins (interface slice + init registration) — simple, type-safe, no OS dependencies
Go plugin package (.so files) — true runtime loading, but only works on Linux, requires same Go version, CGo limitations
gRPC-based plugins — language-agnostic, process isolation, network overhead
Functional options pattern for plugin configuration without breaking the interface
Most production systems prefer compile-time or gRPC plugins over the native plugin package