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.

Contribution Questionnaire

Any dependency changes made to GeoTrellis should be submitted as a new Contribution Questionnaire (CQ) into the ECLIPSE IP Zilla.

Visit and log into the system.

The GeoTrellis project page

On the right, in the COMMITTER TOOLS side bar, you can find a link Create a Contribution Questionnaire

Create a Contribution Questionnaire page

Next, we need to create a Third-Party Code Quest. For this example, we’ll be creating a CQ for pureconfig v0.10.2:

A "piggyback" CQ

When typing in the name/version of the dependency, it may appear in the search bar. If that’s the case, then that means someone else has already sent this dependency to Eclipse’s IP team. Therefore, the CR could be instantly approved if the IP team has already approved of the given dependency.

Let’s create a CQ for pureconfig v0.11.0. There is no such a library, so we’ll have to fill the page manually:

A new CQ

The next step would be to fill in information about it:

A new CQ Step 1

If the library was already submitted but a new version is being requested, you can look at what was already submitted for that library to use as an example. In our case we can use a Pureconfig Version 0.10.2

In the case that the dependency is completely new and has never been validated by the IP team, then one will need to fill in the fields from scratch. However, if there is any uncertainty when filling out the forum, please feel free to contact the GeoTrellis team for help.

Next, you’ll need to go the CQ page and submit any source code released to this CQ (pureconfig v0.10.2 for this example):

Add sources to the CQ

One can find source code for their target library in a number of different locations. The first and probably best place to check is Maven Central search:

Download sources

You may upload multiple sources, in case they are all in the same repository. An example of such a CQ is AWS SDK CQ.

After you uploaded all sources, the next step would be to submit a PMC approval request. To do that, you need to subscribe to the Technology PMC mailing list and to send a request to them for approval. An example of such a request can be found in the Technology PMC mailing list archive. If things are not moving, you can leave your request in the Locationtech Gitter lobby channel and it will be looked at.

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