Sandustry's modding story has two distinct eras, and most confusion comes from mixing them up. If you searched "git sandustry modloader", you found the old era — here is the current picture.
Early Access: Steam Workshop + Sandkit
The full game ships with official Steam Workshop support. Installing a mod is the standard flow: open the game's Workshop page, hit Subscribe, and the mod loads on next launch — no loader, no file copying.
Under the hood, mods are built on the game's official modding API, which the community calls Sandkit. The developer began shipping the official modding framework six days after launch: patch v0.5.5 (August 19, 2026) published it on an unstable "mods" beta branch for testing. If a Workshop mod says it needs the beta branch: right-click the game in Steam → Properties → Betas → select mods.
Notable Workshop mods so far:
- SandTogether — the headliner: up to 4-player co-op over internet or LAN, streaming sand, fluids and factories live between players. The closest thing to multiplayer the game has.
- A steam-turbine tier, electric thermal buffers, and throughput/power readout overlays, maintained by the community's sandustry-mods GitHub organisation.
- A switch that enables the game's own hidden debug tools without touching files (see the cheats & debug guide).
The demo era: Fluxloader
The 2025 free demo had no official mod support, so the community built Fluxloader (originally just "the modloader") — an unofficial loader with its own mod browser that grew a catalogue of roughly 100 mods, including a custom-map loader. It lives on GitHub under the fluxloader-team organisation.
Two things to be clear about:
- Fluxloader is demo-only. The Early Access game uses the Workshop instead; do not install Fluxloader into the full game.
- It remains the only way to mod the demo, which is frozen at its February 2025 state — so the demo mod scene is a preserved snapshot, not a dead end.
Safety notes
Get mods from the Steam Workshop or the linked GitHub organisations only. Sites offering "modded Sandustry" downloads are repackaging the free demo with who-knows-what added — that is the source of the malware rumors around the game, and there is never a reason to touch them: the demo is free from official sources and mods are free on the Workshop.
Mods and the beta branch can break with any Early Access patch (three shipped in launch week alone — see the patch history). If the game misbehaves after an update, unsubscribe from mods and leave the beta branch before reporting bugs.