Faster Than Light
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Slipstream is a mod manager for FTL, making it easy to install multiple mods at the same time and, later, revert to vanilla gameplay.

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Slipstream is a mod manager for FTL, making it easy to install multiple mods at the same time and, later, revert to vanilla gameplay.

It is the successor to Grognak's Mod Manager (GMM). Completely rewritten in Java. A number of planned features will be easier in the new language, and the fresh start gets away from GMM's loooong tech support thread.

As of 1.0, Slipstream worked just like GMM did, but without the bugs that plagued its predecessor.

1.2 introduced new XML tags for modders to use (announcement).



Important: Return FTL to an unmodded state before upgrading or replacing an existing mod manager (details).
And when the game itself gets an upgrade, delete the mod manager's backups so it'll know to make fresh ones.

Version 1.4 - [Windows] - [Mac/Linux]
Version 1.3 - [Windows] - [Mac/Linux]
Version 1.2 - [Windows] - [Mac/Linux]
Version 1.1 - [Windows] - [Mac/Linux]
Version 1.0 - [Windows] - [Mac/Linux]

Uncompiled source is available at GitHub.


I can accept PayPal donations via Sourceforge, or arrange something via PM, if you feel inclined.
That would be fantastic.


Extract the mod manager anywhere.
On startup, it'll either find FTL automatically or ask you to locate it.


Mods come in .ftl files. To make one available to Slipstream, simply drag it into the mods/ folder.

To install mods, open Slipstream, select the mods you want, and hit Patch. Anything not selected is effectively uninstalled.

In order to uninstall all mods, patch with nothing selected.


Link: Java (1.6 or higher).
Link: FTL (1.01-1.03.3, Windows/OSX/Linux, Steam/GOG/Standalone).
WinXP SP1 can't run Java 1.7.
(1.7 was built with VisualStudio 2010, causing a DecodePointer error.)
To get 1.6, you may have to google "jdk-6u45-windows-i586.exe".


On Windows, you may need to right-click modman.exe, and "Run as Administrator" for permission to modify FTL's files.

If you have other problems, check the readme's troubleshooting section.

If all else fails, try asking on this thread.


Grognak: For the long voyage on a Ship of Theseus that was so fun to patch. :P
bas: For his brilliant ftldat.
kartoFlane: For lots of good feature requests.

For Mod Developers

See "readme_modders.txt".

For Software Developers

I've ported (lib for reading/editing FTL resources) to Java:

Import net.vhati.ftldat.FTLDat from modman.jar.

FTLDat.FTLPack dataP = new FTLDat.FTLPack( new File("data.dat"), false );
String innerPath = "data/names.xml";

// Replace a resource.
if ( dataP.contains( innerPath ) ) dataP.remove( innerPath );
dataP.add( innerPath, anInputStreamOfNewContent );

InputStream is = dataP.getInputStream( innerPath ); // Read a resource.
List<String> innerPaths = dataP.list(); // List all resources.

You may find some of the other classes interesting.
They might even be independently useful enough to make modman.jar a workable library for other projects without dissecting the source. :)

If you want to compile this project yourself, see "readme_developers.txt" on GitHub.