Overview

Framework	Plugin language	Loader	Build setup	License
VoltMod	C++23	Its own `server_valve` loader	`voltmod new project`, Conan, and CMake	MIT
CounterStrikeSharp	C# on .NET 8	Metamod:Source	.NET class library	GPLv3 with a plugin exception
SwiftlyS2	C# on .NET 10	SwiftlyS2 loader	`dotnet new` template and `dotnet publish`	GPLv3 with a plugin exception
Plugify for Source 2	C++, C#, Go, Python, JavaScript, Lua, Rust, D, and other language modules	Plugify with the Source 2 SDK plugin	Depends on the installed language module	Plugify is MIT; the Source 2 SDK plugin is GPLv3

VoltMod

VoltMod currently builds native C++23 plugins. One host, started by its own loader with or without Metamod:Source, loads their manifests, checks dependencies, and handles load, unload, and reload commands. The framework includes commands, players, menus, Panorama UI, engine APIs, HTTP, three database drivers, Conan packages, and project tools.

The host and runtime are structured to allow more language bindings later, but only the C++23 SDK is available today. On Windows, a loaded DLL must be unloaded before it can be replaced.

CounterStrikeSharp

CounterStrikeSharp runs C# plugins on .NET 8 through a Metamod:Source plugin. Its documented APIs cover commands, game events, timers, client and map listeners, server information, schema access, and administration. Replacing a plugin DLL triggers automatic hot reload by default.

The server needs the supported .NET runtime. The first installation normally uses the release archive that includes it. See the official installation guide.

SwiftlyS2

SwiftlyS2 has a native core and a C# plugin API. It uses its own loader, so Metamod:Source is not required. Its APIs cover commands, convars, entities, events, hooks, protobuf messages, permissions, translations, timers, traces, profiling, databases, menus, and sound.

Plugins start from the official .NET template and build with dotnet publish. See the development guide.

Plugify for Source 2

Plugify loads language modules and lets plugins written in different languages call one another. Source 2 support comes from a separate SDK plugin. A server installs the Plugify host, the Source 2 SDK plugin, and the language modules its plugins need.

Plugify can run through the Source 2 launcher/runtime or a Metamod loader. See the official installation guide.

Main differences

VoltMod is native C++23 today and includes its build, database, Panorama, and server tools.
CounterStrikeSharp and SwiftlyS2 use managed C# plugins.
VoltMod and SwiftlyS2 use their own loaders; CounterStrikeSharp uses Metamod:Source.
Plugify supports several languages through separate modules.

Future VoltMod language bindings are not included in this comparison until they ship with a documented SDK and compatibility contract.