GameServer Manager v1.0.0: Free, Open Source Game Server Management for Windows
Install, run, and secure dedicated Source engine servers on Windows 11 with one PowerShell tool. No panel, no subscription, no telemetry.
Running a dedicated game server on Windows has always meant a choice between two bad options. You either pay a monthly fee for a commercial control panel, or you do everything by hand: run SteamCMD from the command line, edit config files in Notepad, punch firewall holes yourself, and hope you remember which launch options you changed last month.
GameServer Manager (GSM) is my answer to that. It is a free, open source PowerShell framework that installs, configures, updates, and runs dedicated game servers on Windows 11. No subscription. No account. No telemetry. Version 1.0.0 is out now on GitHub.
Get it here: https://github.com/marclarouche/gameservermanager/releases/tag/v1.0.0
What it manages
GSM ships with plugins for five Source engine games:
Insurgency (2014)
Team Fortress 2
Counter-Strike: Source
Left 4 Dead
Left 4 Dead 2
Each plugin knows its own Steam AppID, executable, default port, maps, game modes, and launch parameters. You pick a game from the menu, GSM handles the rest: SteamCMD download, server installation, configuration, and lifecycle management.
The full feature set
Complete server lifecycle. Install, update, start, stop, restart, and status, all from one menu. GSM downloads and verifies SteamCMD automatically, installs the dedicated server files, and manages the running process. Crash recovery brings a downed server back without your intervention.
Windows service integration. Servers run as proper Windows services through NSSM, so they survive reboots and don’t depend on a logged-in session. GSM bundles a verified NSSM build and wires everything up for you.
Least privilege by default. GSM provisions a dedicated local service account with only the rights it needs. Your game server never runs under your admin account. This is standard practice in enterprise environments and almost unheard of in hobbyist server tooling.
Scheduling. Nightly Workshop content refreshes and scheduled restarts run through the Windows Task Scheduler, configured entirely from GSM’s menu.
Steam Workshop support. Subscribe to Workshop items per server instance for the games that support it (Insurgency, TF2, Left 4 Dead 2). GSM downloads content through SteamCMD and places it where the game expects it. Unsubscribing removes it cleanly.
RCON console. Send commands to a running server directly from GSM. No third-party RCON client needed.
Local web dashboard. A lightweight dashboard runs on your machine, accessible from any device on your LAN. Live status, no cloud dependency.
Backups that fail closed. GSM backs up configuration and state (not the multi-gigabyte game installs) with keep-last-N retention. Restore validates the backup before applying it. If validation fails, nothing changes.
Firewall management. GSM creates and removes Windows Firewall rules per server instance with a consistent, idempotent naming scheme. No orphaned rules, no manual netsh commands.
Health reporting. One click generates a ServerHealth.html report covering installed plugins, open ports, firewall rules, resource usage, backup status, and update history.
Want to support my work? Consider buying me a coffee ☕
Built like security software, because it is
I have spent years in cybersecurity, and I built GSM the way I would expect a tool to be built before it touched one of my systems:
SHA-256 integrity verification on every downloaded file, including SteamCMD and NSSM. Hashes are pinned in config.
Tamper evident logging. Every log entry is chained to the previous one by hash. If someone edits a log line after the fact, the chain breaks and you know.
Strict configuration validation. Invalid ports, duplicate keys, malformed JSON, and unsafe launch options are rejected before they ever reach a running server.
Automatic backups before updates and config changes.
Fully offline. Zero telemetry, zero cloud authentication, zero analytics. The only network calls GSM makes are the ones you ask for: Steam downloads and Workshop content.
Engineering quality
GSM is not a script that grew out of control. It is a modular framework: a core engine plus a plugin contract. Every module carries comment based help, passes PSScriptAnalyzer, and is covered by Pester tests. The v1.0.0 release ships with 531 automated tests passing.
Adding a sixth game does not require touching core code. A plugin is a folder containing a Plugin.json manifest and four modules (install, server, maps, modes). Drop it in the Plugins directory and GSM discovers, validates, and loads it. The contract was proven against five real games with real differences: Workshop support varies, RCON behavior varies, and the loader handles all of it.
Requirements and getting started
Windows 11
PowerShell 7 or later
That is the whole list. Download the release zip, extract it, and run:
./GSM.ps1
GSM walks you through the rest: SteamCMD setup, service account provisioning, game installation, and configuration, all from an interactive menu.
What’s next
GSM v1.0.0 is feature complete against its original design. The plugin architecture means new games are the natural next step, and the codebase is documented specifically so contributors can add them without reading my mind. If you run a Source engine server and want your game supported, open an issue on GitHub.
The project is MIT licensed. Star it, fork it, break it, and tell me what you find.
Repository: https://github.com/marclarouche/gameservermanager Download v1.0.0: https://github.com/marclarouche/gameservermanager/releases/tag/v1.0.0