Getting Started with Slime Rancher Modding

Slime Rancher 1 has one of the gentler entry curves in Unity-game modding. The community converged on a single stack — MelonLoader + SRML — early, the modding API is stable, and most popular mods are a one-line drop into Mods/.

This guide walks through the standard install on Slime Rancher 1 (not Slime Rancher 2 — those are separate ecosystems, see the Slime Rancher 2 guide for that path).

Step 1 — Install MelonLoader

MelonLoader is the Mono-Unity plugin loader Slime Rancher 1 mods run through.

Download the installer (MelonLoader.Installer.exe) from the MelonLoader GitHub releases page. Run it, point it at SlimeRancher.exe, and pick the Latest version of MelonLoader.

After installation, your Slime Rancher folder contains:

version.dll (the MelonLoader hook)
MelonLoader/ (the loader itself + dependencies)
Mods/ (where mods go)
Plugins/ (rarely used for Slime Rancher)

Launch Slime Rancher once. A MelonLoader console window appears alongside the game; the game itself reaches the main menu with a "MelonLoader [version]" tag. Confirm both before continuing.

Step 2 — Install SRML

SRML (Slime Rancher Mod Loader) provides the Slime Rancher–specific helper APIs most content mods depend on.

Download the latest SRML release .dll and drop it into your Slime Rancher Mods/ folder. That's the entire install.

Launch the game. The main menu shows a "Mods" button if SRML loaded correctly, and the MelonLoader console logs SRML's initialisation.

Step 3 — Install your first mod

Three solid first picks:

InstantStartGadgets — bypasses the slow-roll early-game gadget unlock; useful for repeated playthroughs.
InfiniteEnergy — gives the jetpack infinite charge. Quality-of-life that doesn't change combat.
NoMoreCrashes — error-handling overlay that catches mod-induced crashes and lets the game continue instead of hard-killing.

Drop each .dll into Mods/. Restart Slime Rancher. The Mods menu now lists your installed mods, each with a version and an enable/disable toggle.

Step 4 — Saves

Slime Rancher saves live at %AppData%/../LocalLow/Monomi Park/Slime Rancher/. Back up the folder before adding any content-additive mod (new slime types, new resources, new zones). Pure-script mods (gameplay tweaks, UI changes) are removable cleanly.

If a save loads with warnings about missing slime types, you can usually save-edit-and-continue, but starting fresh is safer.

Step 5 — Multiplayer

Slime Rancher 1 is single-player only. There is no multiplayer with or without mods. (Slime Rancher 2 has experimental co-op; that's a separate game.)

Common gotchas

Wrong MelonLoader version. Slime Rancher's stable build is Mono Unity 2019.x. MelonLoader builds older than that won't recognise the runtime. The installer's "Latest" channel handles this — only override if a specific mod explicitly demands an older MelonLoader.
SRML version mismatch. Major SRML versions sometimes change their plugin API. A mod targeting SRML 0.x won't load on SRML 1.x. Check the mod's README for SRML version requirements.
Mod ordering doesn't matter (usually). SRML loads mods in alphabetical order and most mods are designed to be order-independent. If you do hit a load-order issue, prefixing a mod's filename with _ forces it to load first.
MelonLoader console is your friend. When a mod fails to load, the console window prints the stack trace. Read it before asking on Discord — most issues are obvious from the first error line.
Removing a mod mid-save. Removing a content mod (new slimes, new zones) corrupts existing saves of that file. Either keep the mod installed or roll back to a pre-mod save backup.

That's the full install loop. Slime Rancher's mod community is small but stable — most popular mods see at least occasional updates years after first release.