What does SaveSync actually do?

It keeps one game save in sync across several players' PCs. After whoever hosted finishes a session, SaveSync uploads the world and pushes it to everyone else in the share group, so any of them can load it and host next time.

Is SaveSync a server?

No. Nothing runs while you're not playing, and nobody connects to a machine you rent. SaveSync moves the save file between players; the game itself is still hosted by whichever player launches it.

Do all my friends need SaveSync?

Yes. Every player who wants to receive the world and host a session needs it installed. Someone who only ever joins as a guest doesn't strictly need it, but then they can never host.

What does SaveSync cost?

A one-time purchase on Steam - no subscription. The same install covers Scrap Mechanic plus 45+ other supported co-op games.

Can SaveSync overwrite our world with an old version?

It syncs the most recent session's save, and it keeps a snapshot history with timestamps and the name of whoever uploaded each one. If a bad version does land, you restore an earlier snapshot instead of losing the world.

Does SaveSync work with Scrap Mechanic Creative mode and Blueprints?

SaveSync is built around sharing world saves, which is where the co-op problem lives. Blueprints are stored separately by the game in their own folder, so treat those as a personal collection rather than something the group shares.

SaveSync for Scrap Mechanic Explained

If you play Scrap Mechanic Survival with friends, you’ve hit this: the world only exists on one person’s PC. They’re offline, so nobody plays. That’s not a bug in your group’s scheduling - it’s how the game works.

SaveSync exists to fix exactly that. This page explains what it is, what it does to your Scrap Mechanic world, and when it’s actually worth having.

What SaveSync Is

SaveSync is a small Steam app that keeps one game save in sync across several players’ machines.

That’s the whole idea. It’s not a server, not a mod, and not something that changes how the game runs. It watches the save file for the games it supports, and when a session ends, it copies the latest version to everyone you’ve shared it with.

The result: the Scrap Mechanic world stops being “Dave’s world” and becomes the group’s world. It sits on your drive, on Dave’s drive, and on everyone else’s.

What SaveSync Is Not

Worth being clear, because people assume one of these:

It’s not a dedicated server. Nothing runs 24/7, there’s no IP to connect to, and there’s no monthly bill. Scrap Mechanic multiplayer is still host-based - one player opens the world, friends join through Steam. SaveSync just makes sure any of you can be that player.
It’s not a mod. It doesn’t inject anything into the game, so it doesn’t break with updates or interfere with the Workshop.
It’s not cloud storage you manage. You’re not dragging files into a Drive folder and telling people which one is newest. That’s the manual method SaveSync replaces.

How It Works With Scrap Mechanic

Scrap Mechanic stores each Survival world as a single .db database file, tucked away under your user folder:

%APPDATA%\Axolot Games\Scrap Mechanic\User\User_<your SteamID>\Save

SaveSync knows that path. You point it at the world once, and from then on the cycle is:

Someone loads the shared world and hosts a session. Friends join as normal.
The host closes the game. SaveSync uploads the updated world.
Everyone else’s copy updates in the background.
Next session, whoever is online first loads the world and hosts. Nobody waits.

You never open the save folder, never zip anything, never post a file in Discord and hope the right person downloads it.

Setting It Up

Every player installs SaveSync from Steam.
Whoever currently has the world opens SaveSync and picks Scrap Mechanic from the game list.
Click + New Save and select the Survival world.
Click the share icon, search each friend’s Steam username, and share.
Friends click Activate on the shared world in their own SaveSync.

That’s it - a minute, once. From then on it’s automatic.

What You Get Beyond “Anyone Can Host”

Save history. Every sync is a stored snapshot with a timestamp and the name of whoever uploaded it. If a session goes wrong - a build wrecked, a world acting strange after a patch - you restore the version from before it instead of eating the loss.

A backup that isn’t on one drive. Because every player holds a copy, a dead SSD or a reinstalled PC doesn’t end a hundred-hour base. This happens to groups more often than you’d think.

No stale-copy accidents. The manual method’s classic failure is someone hosting a three-week-old copy and quietly wiping out a weekend of drilling. SaveSync tracks which version is current so nobody has to.

Other games included. The same install covers 45+ supported co-op games, so it’s not a Scrap Mechanic-only purchase.

When You Actually Need It

Be honest about your group - it’s not for everyone.

Probably not worth it if: you play Scrap Mechanic solo, or it’s two of you and the same person always hosts and is always around.

Worth it if:

Three or more of you play, on different schedules.
You’ve ever cancelled a session because the host wasn’t on.
You’ve got a long-running Survival base you’d be genuinely annoyed to lose.
Someone in the group is the “world holder” and everyone quietly worries about it.
You play other co-op survival games with the same friends.

What It Costs

A one-time purchase on Steam. No subscription, no per-world fee, nothing that renews. Compare that to renting a machine to sit online hosting Scrap Mechanic for you - that’s a monthly cost forever, for a job that’s really just “move one file to the right person.”

The Short Version

Scrap Mechanic ties the world to whoever hosts. SaveSync unties it, so the world belongs to the group and the person who’s free tonight is the one who plays.

SaveSync on Steam - one-time purchase, covers Scrap Mechanic and 45+ other co-op games.