The dedicated server is implemented in C# on .NET 8. Python is not used by the server runtime, utilities, test suite, launch scripts, or Host GUI integration.

Valve GameNetworkingSockets remains in the native C++ bridge under native_transport/. The C# server loads its C ABI directly.

Run

Packaged Windows:

CommonwealthOnline.Server.exe serve --config commonwealth-server.json

Packaged Linux:

./CommonwealthOnline.Server serve --config commonwealth-server.json

Source checkout:

dotnet build CommonwealthOnline.Server.csproj -c Release
dotnet run --project tests/CommonwealthOnline.Server.Tests.csproj -c Release
dotnet run --project CommonwealthOnline.Server.csproj -- serve --config commonwealth-server.json --interactive

start.bat and start.sh prefer a published apphost, then a framework-dependent DLL, then dotnet run in a source checkout.

Config

Generate defaults:

dotnet run --project CommonwealthOnline.Server.csproj -- config init commonwealth-server.json

Existing field names remain supported:

{
  "host": "0.0.0.0",
  "port": 7777,
  "server_name": "Commonwealth Online Server",
  "server_description": "",
  "max_players": 16,
  "log_verbosity": "info",
  "admin_port": 7779,
  "enable_gns_transport": false,
  "gns_bridge_path": null
}

When GNS is enabled, host must be an explicit IPv4 bind address. TCP and GNS may use the same numeric game port because they use TCP and UDP separately.

Ports

TCP 7777 by default: gameplay compatibility
UDP 7777 by default: GNS gameplay when enabled
UDP 7778: LAN discovery
TCP 127.0.0.1:7779 by default: authenticated administration

Admin CLI

dotnet run --project CommonwealthOnline.Server.csproj -- status --config commonwealth-server.json
dotnet run --project CommonwealthOnline.Server.csproj -- clients --config commonwealth-server.json
dotnet run --project CommonwealthOnline.Server.csproj -- kick 2 --reason griefing --config commonwealth-server.json
dotnet run --project CommonwealthOnline.Server.csproj -- ban 2 --reason griefing --config commonwealth-server.json
dotnet run --project CommonwealthOnline.Server.csproj -- unban 192.0.2.5 --config commonwealth-server.json
dotnet run --project CommonwealthOnline.Server.csproj -- bans --config commonwealth-server.json
dotnet run --project CommonwealthOnline.Server.csproj -- world time 1430 --config commonwealth-server.json
dotnet run --project CommonwealthOnline.Server.csproj -- world weather 0002b52a --config commonwealth-server.json

The admin channel authenticates with .admin-token beside the config file and binds to localhost only.

Load test

The C# synthetic Protocol V2 client replaces the old scripted fake clients:

dotnet run --project CommonwealthOnline.Server.csproj -- load-test --host 127.0.0.1 --port 7777 --clients 16

Architecture

C# owns:

Protocol V2 decoding/validation
session admission and server-owned player IDs
movement validation and corrections
cell/worldspace interest filtering
durable player state
scoped NPC authority and epochs
combat routing
world state
bans and rate limits
handshake and idle timeouts
TCP compatibility
GNS sequencing/envelope handling
LAN discovery
admin control

C++ owns only the Valve GNS transport bridge:

initialization/shutdown
UDP listen socket
GNS connection lifecycle
message polling/sending
disconnects
remote endpoint lookup

Protocol guarantees

Maximum message size remains 64 KiB.
transform and npcState are unreliable/sequenced under GNS.
Reliable gameplay/control packets remain reliable/ordered.
Snapshot sequences are wrap-safe; stale and duplicate snapshots are rejected.
Server-owned identity is applied before mutation/relay.
Movement validation runs before transform mutation/relay.
Interest filtering remains authoritative.
NPC authority is scoped by cell/worldspace and epoch.
Durable player state is cached; action events are not replay-cached.
Ban, connection throttle and packet-rate checks remain server-side.

Publish

Linux self-contained:

dotnet publish CommonwealthOnline.Server.csproj -c Release -r linux-x64 --self-contained true -p:PublishSingleFile=true -o publish/linux-x64

Windows self-contained:

dotnet publish CommonwealthOnline.Server.csproj -c Release -r win-x64 --self-contained true -p:PublishSingleFile=true -o publish\win-x64

commonwealth-online.service.example is provided for Linux systemd deployment.