Sandustry

Sandustry Co-op Multiplayer in Early Access

Sandustry has no native multiplayer yet. The community mod SandTogether adds 4-player shared-world co-op over internet or LAN. Here is how to install it, host or join a session, and avoid the common setup traps.

Up to 4 players Steam Workshop mod Shared world + progression

The core situation

Sandustry is single-player only at launch

Sandustry launched into Early Access with no native co-op or multiplayer. The developer lists official multiplayer as backlog work, with no firm timeline, because the pixel/sand physics simulation is hard to sync. The practical solution players are using right now is the open-source community mod SandTogether on Steam Workshop, which enables a shared live world for up to 4 players.

Step 1

Subscribe to the SandTogether mod

1Open Steam Workshop for Sandustry. Search for "SandTogether - Co-op Multiplayer" and subscribe so Steam downloads the mod files.
2Wait for the download to finish before running the installer. Steam will place the files under steamapps/workshop/content/2764460/3784750764/.
3Both host and joining players must subscribe. Mismatched mod versions break tool sync, research sync, and connections.

Step 2

Run the one-time installer

Sandustry has no built-in mod loader yet. You must run the installer once per machine, otherwise the Multiplayer button never appears in the main menu.
1Locate the mod folder. In Steam, right-click Sandustry, Manage, Browse local files. Go up one folder, then navigate into steamapps/workshop/content/2764460/3784750764/.
2Windows: right-click install.bat and Run.
3macOS: double-click install.command, then use the provided launcher or Steam.
4Linux: in a terminal run bash install-linux.sh.
5If you installed an early August build and updates never arrive, run the installer one more time. A temporary bug broke the auto-updater in some early builds; later versions fix it permanently.

Step 3

Launch and verify the mod is active

1Launch Sandustry normally. A Multiplayer button now appears in the main menu.
2Check the SandTogether panel in the top-right. It shows status (OFFLINE / HOSTING / CONNECTED), player list, ping, and mod version.
3Press Ctrl+Shift+H or click the panel header to collapse it if it gets in the way.

Step 4

Host or join a session

Pick a hosting method based on your network and how much setup you want. The host's save and progression are authoritative, so decide whose world to advance before starting.

Host (Internet - direct)

Preferred for performance. Uses UPnP to open the port automatically. The address is shown masked with a copy button. Friend pastes it into Join by address. Avoids Steam relay throttling.

Host (Steam) + Invite

Zero setup. Invite from the Steam friends list. Simplest path if both players are on Steam and just want it to work.

Host LAN / Join by address

Same network or VPN (Tailscale works well). On the same local network use the local 192.168.x.x address, not the public one.

Join by Lobby ID

Paste an ID shared by the host. Useful when direct address or Steam invite is not available.

1Host picks a method from the Multiplayer menu.
2Choose Load last save & PLAY or select a specific save. The host's world is sent automatically to joiners.
3Set nicknames in the lobby so teammates are easy to identify.
4Joiners paste the address or Lobby ID and connect. The world loads from the host on join.

Step 5

Play in the shared world

The shared simulation is live for everyone. Dig, build and demolish, place pipes, wiring and blueprints, use all tools (shovel, vacuum, flamethrower), research, upgrades, story objectives and progression are all tied to the host world.
1Teammates are visible with player models, ghosts when far away, off-screen arrows, and team chat.
2Auto-reconnect is supported. If a player drops, they can rejoin the same session.
3Steam achievements still work while the mod is active.
4If the world looks desynced, use the panel's Resync button. Ctrl+Shift+H collapses the panel.

Key decisions

Choices to make before you start

Wait for official or use the mod?

If you want a polished, supported experience and can wait, stick to single-player. Early Access is planned for roughly a year. If you want to play with friends now, SandTogether is the working solution and is actively updated.

Which hosting method?

Direct internet for best latency when UPnP is available. Steam invite for simplest setup. LAN or VPN (Tailscale) for local or reliable private connections.

Whose save is authoritative?

The host's world and progression are the source of truth. Everyone shares that world's research, tools, and unlocks. Decide whose save to advance before starting.

How stable is it today?

The mod is community-built and iterates fast. Early reports noted client shovel, filter/config sync, and research sync issues. Author and contributors push same-day or next-day fixes; re-run the installer and match versions to resolve most issues.

Common pitfalls

Mistakes to avoid

XSkip the one-time installer. Without running install.bat / install.command / install-linux.sh, the Multiplayer button never appears in the main menu.
XMismatched game or mod versions. The panel shows red warnings and tool, research, or connection sync can break. Always update both sides and re-run the installer if needed after early builds.
XExpecting perfect stability on day one of a mod. Same-day fixes are common. Check the Workshop discussions for the latest notes and report issues with logs (%APPDATA%\Sandustry\logs\main.log on Windows; similar paths on macOS/Linux).
XUsing the public address while both players are on the same local network. Use the local 192.168.x.x address instead, or the public address will often fail from inside the network.
XAssuming official multiplayer is already in or imminent. Developer comments treat it as backlog work with no firm timeline. Use the mod if you want co-op now.
XSwitching hosts mid-session expecting progression to carry. The host world is authoritative. Pick one host and stick with that save for the whole playthrough.