Build selection guide
Start a new server on Build 42 Stable, or choose Build 41 Legacy for compatibility with an established Build 41 world. The right choice depends on the world and mod set you need—not on an in-place save upgrade.
Choose from your actual constraint
Version selection is about compatibility. It does not convert a Build 41 save into a Build 42 save.
Recommended for a new server
Use the current stable branch when you are starting a new world and your players and required mods are ready for Build 42.
Choose for Build 41 compatibility
Use the legacy branch when an existing Build 41 world or its mod requirements determine the target version. Keep a verified build-specific backup before any version switch.
Managed version switch
Metrly keeps the compatibility warning and a default-on backup step in the version-switch flow. After the clean reinstall, restore only a world and mods that match the selected build, and confirm every player uses that build.
Select Build 42 Stable or Build 41 Legacy and review the compatibility warning before changing the server.
The option is on by default. Metrly completes and verifies the backup before changing the Steam branch; keep that backup tied to the build that created it.
Metrly stops the server, updates the selected Steam branch, clears the live server files, and performs a clean installation of the chosen build.
After the clean install, restore only a world and mod set that match the selected build, then confirm every player uses that build. Restore the prior build-specific backup to return.
Before you switch
These answers separate Metrly’s managed server workflow from the game’s upstream save-compatibility limits.
Build 42 Stable is Metrly's recommended default for a new server. Choose Build 41 Legacy when an established Build 41 world or its mod requirements are the deciding constraint.
No. The Project Zomboid developers state that Build 41 saves are not compatible with Build 42. Treat a Build 42 world as a separate world and retain a verified Build 41 backup.
With the default safety-backup option enabled, Metrly creates and verifies a backup, stops the server, updates the selected Steam branch, clears the live server files, and performs a clean reinstall. Returning to the prior world requires restoring the matching build-specific backup.
Keep the verified Build 41 backup and do not overwrite it with Build 42 data. Metrly provides backup-based recovery, but you still need to confirm that the restored world, mods, and every player client match Build 41.
Choose before you register
Select Project Zomboid, choose a location and server settings, and review the estimated typical monthly cost before continuing.