We value all kinds of contributions from the community, not just actual code. Perhaps the easiest and yet one of the most valuable ways of helping us improve GeoTrellis is to ask questions, voice concerns or propose improvements on the Mailing List.

If you do like to contribute actual code in the form of bug fixes, new features or other patches this page gives you more info on how to do it.

Building GeoTrellis

  1. Install SBT (the master branch is currently built with SBT 0.13.12).
  2. Check out this repository.
  3. Pick the branch corresponding to the version you are targeting
  4. Run sbt test to compile the suite and run all tests.

Style Guide

We try to follow the Scala Style Guide as closely as possible, although you will see some variations throughout the codebase. When in doubt, follow that guide.

Git Branching Model

The GeoTrellis team follows the standard practice of using the master branch as main integration branch.

Git Commit Messages

We follow the ‘imperative present tense’ style for commit messages. (e.g. “Add new EnterpriseWidgetLoader instance”)

Issue Tracking

If you find a bug and would like to report it please go there and create an issue. As always, if you need some help join us on Gitter to chat with a developer.

Pull Requests

If you’d like to submit a code contribution please fork GeoTrellis and send us pull request against the master branch. Like any other open source project, we might ask you to go through some iterations of discussion and refinement before merging.

As part of the Eclipse IP Due Diligence process, you’ll need to do some extra work to contribute. This is part of the requirement for Eclipse Foundation projects (see this page in the Eclipse wiki You’ll need to sign up for an Eclipse account with the same email you commit to github with. See the Eclipse Contributor Agreement text below. Also, you’ll need to signoff on your commits, using the git commit -s flag. See for more info.

Eclipse Contributor Agreement (ECA)

Contributions to the project, no matter what kind, are always very welcome. Everyone who contributes code to GeoTrellis will be asked to sign the Eclipse Contributor Agreement. You can electronically sign the Eclipse Contributor Agreement here.

Editing these Docs

Contributions to these docs are welcome as well. To build them on your own machine, ensure that sphinx and make are installed.

Installing Dependencies

Ubuntu 16.04

> sudo apt-get install python-sphinx python-sphinx-rtd-theme

Arch Linux

> sudo pacman -S python-sphinx python-sphinx_rtd_theme


brew doesn’t supply the sphinx binaries, so use pip here.


> pip install sphinx sphinx_rtd_theme

Building the Docs

Assuming you’ve cloned the GeoTrellis repo, you can now build the docs yourself. Steps:

  1. Navigate to the docs/ directory
  2. Run make html
  3. View the docs in your browser by opening _build/html/index.html


Changes you make will not be automatically applied; you will have to rebuild the docs yourself. Luckily the docs build in about a second.

File Structure

When adding or editing documentation, keep in mind the following file structure:

  • docs/tutorials/ contains simple beginner tutorials with concrete goals
  • docs/guide/ contains detailed explanations of GeoTrellis concepts
  • docs/architecture contains in-depth discussion on GeoTrellis implementation details