What is the Go plugin system?

Go supports building shared libraries as plugins using go build -buildmode=plugin, producing a .so file. The main program loads it at runtime with plugin.Open("myplugin.so"), then looks up exported symbols with p.Lookup("MyFunc") and type-asserts to the expected function or variable type. This allows dynamically loading functionality without recompiling the main binary — useful for extensible applications and driver models. Significant limitations: plugins only work on Linux and macOS, both the plugin and host must be compiled with the same Go toolchain version and module paths, and there is no way to unload a plugin. In practice, many teams prefer interface-based extension points or GRPC-based plugin systems (like HashiCorp's go-plugin) for better portability.