Contributing to sbt 

Below is a running list of potential areas of contribution. This list may become out of date quickly, so you may want to check on the sbt-dev mailing list if you are interested in a specific topic.

  1. There are plenty of possible visualization and analysis opportunities.

    • ’compile’ produces an Analysis of the source code containing

      • Source dependencies
      • Inter-project source dependencies
      • Binary dependencies (jars + class files)
      • data structure representing the API of the source code There is some code already for generating dot files that isn’t hooked up, but graphing dependencies and inheritance relationships is a general area of work.
    • ’update’ produces an [Update Report][Update-Report] mapping Configuration/ModuleID/Artifact to the retrieved File
    • Ivy produces more detailed XML reports on dependencies. These come with an XSL stylesheet to view them, but this does not scale to large numbers of dependencies. Working on this is pretty straightforward: the XML files are created in ~/.ivy2 and the .xsl and .css are there as well, so you don’t even need to work with sbt. Other approaches described in the email thread
    • Tasks are a combination of static and dynamic graphs and it would be useful to view the graph of a run
    • Settings are a static graph and there is code to generate the dot files, but isn’t hooked up anywhere.
  2. There is support for dependencies on external projects, like on GitHub. To be more useful, this should support being able to update the dependencies. It is also easy to extend this to other ways of retrieving projects. Support for svn and hg was a recent contribution, for example.
  3. Dependency management: see adept
  4. If you like parsers, sbt commands and input tasks are written using custom parser combinators that provide tab completion and error handling. Among other things, the efficiency could be improved.
  5. The javap task hasn’t been reintegrated
  6. Implement enhanced 0.11-style warn/debug/info/error/trace commands. Currently, you set it like any other setting:
set logLevel := Level.Warn

or : set logLevel in Test := Level.Warn

You could make commands that wrap this, like:

warn test:run

Also, trace is currently an integer, but should really be an abstract data type.

​7. Each sbt version has more aggressive incremental compilation and reproducing bugs can be difficult. It would be helpful to have a mode that generates a diff between successive compilations and records the options passed to scalac. This could be replayed or inspected to try to find the cause.


  1. There’s a lot to do with this documentation. If you check it out from git, there’s a directory called Dormant with some content that needs going through.
  2. the main page mentions external project references (e.g. to a git repo) but doesn’t have anything to link to that explains how to use those.
  3. API docs are much needed.
  4. Find useful answers or types/methods/values in the other docs, and pull references to them up into /faq or /Name-Index so people can find the docs. In general the /faq should feel a bit more like a bunch of pointers into the regular docs, rather than an alternative to the docs.
  5. A lot of the pages could probably have better names, and/or little

    2-4 word blurbs to the right of them in the sidebar.


sbt Reference Manual
    1. Contributing to sbt