798 ratings
Mod, 1.4, 1.5
File Size
4.044 MB
Feb 16, 2023 @ 1:33pm
Apr 28 @ 8:25am
23 Change Notes ( view )

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Prepatcher is most importantly a powerful tool for mod developers. The project also includes a mod manager which runs before the game loads.

The mod manager - Prestarter
Prestarter is still in more of a preview state currently and I'll be expanding it in the near future. It's already very convenient though.

  • Runs before the game loads
  • Press Space while the game is loading to open (unfortunately only after a message saying you can do so appears on screen)
  • Load, save, copy and paste mod lists
  • Undo/redo while editing (Ctrl-Z/Ctrl-Shift-Z)

Relation to Harmony
With Brrainz's permission, Prepatcher is an alternative provider of the Harmony library for RimWorld mods. This means that:
  • Prepatcher can be used in place of the Harmony mod (brrainz.harmony). In practice, this is done by patching the mod loading system to make Prepatcher satisfy dependencies on Harmony.
  • Having both the Harmony mod and Prepatcher active won't cause any problems

Prepatcher has no dependencies on other mods.

Load order
Prepatcher should go first in the mod list, above Core and expansions. Its placement relative to Harmony doesn't matter, it can be put below or above it.

For modders
Prepatcher doesn't do anything on its own, it's only useful when other mods depend on it.
The library provides patching capabilities beyond those of Harmony. Currently these are:
  • Adding fields to types
  • Free editing of the game's assembly before the game starts
Visit the Github wiki for more information.

Prepatcher builds upon other great software. Thanks to Brrainz for Harmony, 0x0ade for MonoMod and jbevain for Mono.Cecil (and anyone who ever contributed to these projects!).

When you encounter an issue you think might be caused by Prepatcher, the information on what happened is most likely contained in RimWorld's error log (Player.log).

Please upload your log file somewhere like pastebin.com and paste the link here or, ideally, post a bug report at: https://github.com/Zetrith/Prepatcher/issues

Location of RimWorld's error log file (Player.log):
  • Windows shortcut: Press Win+R, type appdata and hit enter, go to LocalLow\Ludeon Studios\RimWorld by Ludeon Studios
  • Windows path: %USERPROFILE%\Appdata\LocalLow\Ludeon Studios\RimWorld by Ludeon Studios\Player.log
  • Linux: ~/.config/unity3d/Ludeon Studios/RimWorld by Ludeon Studios/Player.log
  • Mac: ~/Library/Application Support/RimWorld/Player.log

Issue reports and suggestions: https://github.com/Zetrith/Prepatcher/issues
Github: https://github.com/Zetrith/Prepatcher
Dev wiki: https://github.com/Zetrith/Prepatcher/wiki
Standalone download: https://github.com/Zetrith/Prepatcher/ (click Code -> Download zip)

Popular Discussions View All (2)
Nov 16, 2023 @ 1:35pm
black screen when i try to open the mod manager
Nov 16, 2023 @ 1:32pm
Black Screen after using Prepatcher
The Gaming Archaeologist
Alu Jul 6 @ 7:40pm 
the reason prepatcher can replace harmony
is cause it includes harmony
so it definitly cant be harmony causing it
Daevinski Jul 6 @ 7:30pm 
I'm not 100% sure, but I at least on my end all the issues with black screens and the debug window popping non-stop were caused by Harmony. I disabled Harmony and kept only Prepatcher, since in the description says it can replace Harmony no problem... and now my game is starting normally with +200 mods with logs not being flooded with errors very fast launch.

Not sure if it's something with 1.5 or with Harmony, but at least now I can play. I just want to know if I can keep it that way and if all Harmony mods will really work no problem.
RiskyBusiness Jul 5 @ 8:54am 
Forgot I left some comments here. I fixed mine by running vanilla Rimworld, then, enabling no more than 15 mods at a time (I usually did 10), running Rimworld after activating some mods, closing it, activating more, repeat. Tedious, but it worked.
Magikarp Jul 5 @ 5:12am 
I am at a loss, with only prepatcher, harmony, perfomance fish, and fishery I am getting consistent black screen, had to spit my log into 2 parts: part 1: https://pastebin.com/k0CZnUZ6 Part 2: https://pastebin.com/7b73Vkzn
RiskyBusiness Jun 13 @ 2:54pm 
Update: before disabling PF, my game would black screen and neither verifying nor deleting the RocketMan folder worked. After disabling PF, it is now back to the original issue where it will black screen every second launch, and verifying fixes it. I'm not sure if it really is this mod causing it, but I'm leaving this here just in case.
RiskyBusiness Jun 12 @ 3:09pm 
Had a couple comments before, deleted because I decided to not be an idiot and just test it myself. The mod causing the issue, at least for me, is Performance Fish. Disabling that with both Prepatcher and RocketMan enabled worked.
Atrax May 30 @ 8:13pm 
I hope the Author can ping this Issue cause i have found 1 good answer in google after some time.

If your stuck at Injecting Mod-XML on 27% and is stops there with infinite loading -> the fault is rocketman,
you need to disable the XML Caching option (listed in Experimental features as Opt-in RocketMan beta features, says google)....
But i haven`t found that option yet, both ingame and in the config files.

My solution: If you can`t start the Game because of that Bug: press windowsbutton+R, type in Appdata and press Enter-> open LocalLow Folder ->Ludeon Studios->RimWorld by Ludeon Studios and delete the RocketMan Folder.
Then go to Rimworld Proberties in Steam and click on Local Files and verify intergrity of Files. Works for me.
四笑行者 May 24 @ 7:22pm 
still cant load this with any mod, just stack in a empty black screen
Alu May 19 @ 9:18am 
you could read the names
fish is by bradson
17 May 18 @ 9:47pm