CSM TM:PE Sync keeps Cities: Skylines Multiplayer (CSM) host-authoritative while players edit Traffic Manager: President Edition (TM:PE) features. After the latest restructuring the synchronization layer has been rewritten feature by feature: every TM:PE tool now owns its own command handlers, network payloads, and harmony patches.

Beta disclaimer

The rewrite is still stabilising. Multiplayer sessions should treat this build as experimental and report issues with logs. Use the mod in controlled test games before deploying it to long-running cities.

Detailed docs live alongside the code. Every feature description is bilingual (German first, English second) and explains file layout, message flow, and known limitations.

The Lane Connector guide has been refreshed to cover the lane-ID apply pipeline rewrite - revisit docs/LaneConnector.md for the new retry/backoff flow and message format details.

Check the corresponding src/CSM.TmpeSync.<FeatureName>/ project when you extend or debug a specific tool. Each project ships its own bootstrapper and harmony integration and can be iterated in isolation.

The automation targets Windows with PowerShell 7. Install the following tools:

The build script mirrors dependencies from Steam Workshop downloads. Make sure the following items are subscribed and fully downloaded in Steam before running the setup wizard:

• Harmony 2
• Traffic Manager: President Edition
• Cities: Skylines Multiplayer

During configuration the script explicitly asks you to confirm these subscriptions. Answering No aborts the process so you can subscribe and retry.

1. Clone the repository (submodules will be initialized by the update script):

   git clone https://github.com/bonsaibauer/CSM.TmpeSync.git
   cd CSM.TmpeSync

2. Launch the configuration wizard:

   pwsh ./scripts/build.ps1 -Configure

   The wizard guides you through:

   • Selecting the Steam profile (currently the only option).
   • Confirming that Harmony, TM:PE, and CSM are subscribed in Steam.
   • Entering the Cities: Skylines installation directory (default: C:\Program Files (x86)\Steam\steamapps\common\Cities_Skylines).
   • Entering the local mod installation root (default: %LOCALAPPDATA%\Colossal Order\Cities_Skylines\Addons\Mods).

   Defaults for the Steam Workshop cache and dependency mirrors are pre-populated and stored alongside the paths you provide in scripts/build-settings.json.

scripts/build.ps1 drives the entire process:

pwsh ./scripts/build.ps1 -Update -Build -Install -Configuration Debug   # refresh dependencies, build the mod, build debug version and install to the configured directory
pwsh ./scripts/build.ps1 -Update -Build -Install                        # refresh dependencies, build the mod, install to the configured directory
pwsh ./scripts/build.ps1 -Build -Install                                # build the mod, install to the configured directory
pwsh ./scripts/build.ps1 -Build                                         # build only (assumes dependencies are already mirrored)
pwsh ./scripts/build.ps1 -Install                                       # copy the latest build output into your mods folder

Key parameters:

• -Configuration <Release|Debug> – build configuration (Release by default).
• -Profile Steam – explicitly target the Steam profile when multiple profiles become available.
• -ModDirectory <path> – override the installation target for a single run.
• -GameDirectory, -SteamModsDir, -HarmonySourceDir, -CsmSourceDir, -TmpeSourceDir – override paths captured in the profile when needed.

Dependency updates copy the latest Harmony, TM:PE, and CSM libraries from Steam into the working cache. Remove those directories to force a clean refresh. The build prefers MSBuild from Visual Studio Build Tools and automatically falls back to the dotnet CLI only when MSBuild is unavailable.

Package the contents of src/CSM.TmpeSync/bin/<Configuration>/net35/ together with scripts/install.ps1. On the target machine run:

pwsh ./scripts/install.ps1

The installer clears any existing copy of the mod and copies the DLL (and optional PDB files) into the default Cities: Skylines mods directory. Use -ModDirectory to override the destination.

1. Enable Harmony, CSM, TM:PE, and CSM.TmpeSync (Beta) in the Cities: Skylines Content Manager.
2. Start or join a CSM session. Once connected, every TM:PE edit made by the host is validated, applied through the feature-specific bridge, and broadcast to all clients.
3. Monitor the daily log files (%LOCALAPPDATA%\Colossal Order\Cities_Skylines\CSM.TmpeSync\log-<YYYY-MM-DD>.log) for warnings while the Beta stabilises.

Operational logs are written to daily rolling files:

%LOCALAPPDATA%\Colossal Order\Cities_Skylines\CSM.TmpeSync\log-<YYYY-MM-DD>.log

Debug-level entries are always written, so you get full bridge traces without additional setup.

File issues with reproduction steps, the latest log-<YYYY-MM-DD>.log, and the feature name that triggered the problem. The modular architecture lets us iterate on one feature at a time, so accurate reports keep the Beta moving forward.

If this project has helped you in any way, do buy me a coffee so I can continue to build more of such projects in the future and share them with the community!