Contributing to Ibis

Clone the Repository

To contribute to ibis you need to clone the repository from GitHub:

git clone

Set Up a Development Environment

  1. Install miniconda
  2. Create a Conda environment suitable for ibis development:

If you are developing for the Impala, Kudu, HDFS, PostgreSQL, MySQL, SQLite, Pandas, Clickhouse, BigQuery, and/or OmniSciDB backend(s):

    conda env create -n ibis-dev --file ci/requirements-dev-3.7-main.yml

If you are developing for the PySpark or Spark backend:

    conda env create -n ibis-dev --file ci/requirements-dev-3.7-pyspark-spark.yml
  1. Activate the environment

    conda activate ibis-dev
  2. Install your local copy of Ibis into the Conda environment. This also sets up a pre-commit hook to check style and formatting before committing.

    make develop

Run the Test Suite

Contributor Krisztián Szűcs has spent many hours crafting an easy-to-use docker-compose setup that enables ibis developers to get up and running quickly.

For those unfamiliar with docker, and docker-compose, here are some rough steps on how to get things set up:

First, start the database services and load the test data:

make --directory ibis init

To run tests for all backends except PySpark and Spark:

make --directory ibis testmain

To run tests for the PySpark backend:

make --directory ibis testpyspark

You can run tests for a custom subset of backends:

make --directory ibis testparallel BACKENDS='omniscidb impala'

or start database services for a specific subset of backends:

make --directory ibis init BACKENDS='omniscidb impala'

make for targets test and testparallel automatically do restart of services (as a prerequisite)

You can also run pytest tests on the command line if you are not testing integration with running database services. For example, to run all the tests for the pandas backend:

pytest ./ibis/pandas

Style and Formatting

We use flake8, black and isort to ensure our code is formatted and linted properly. If you have properly set up your development environment by running make develop, the pre-commit hooks should check that your proposed changes continue to conform to our style guide.

We use numpydoc as our standard format for docstrings.

Commit Philosophy

We aim to make our individual commits small and tightly focused on the feature they are implementing. If you find yourself making functional changes to different areas of the codebase, we prefer you break up your changes into separate Pull Requests. In general, a philosophy of one Github Issue per Pull Request is a good rule of thumb, though that isn't always possible.

We avoid merge commits (and in fact they are disabled in the Github repository) so you may be asked to rebase your changes on top of the latest commits to master if there have been changes since you last updated a Pull Request. Rebasing your changes is usually as simple as running git pull upstream master --rebase and then force-pushing to your branch: git push origin <branch-name> -f.

Commit/PR Messages

Well-structed commit messages allow us to generate comprehensive release notes and make it very easy to understand what a commit/PR contributes to our codebase. Commit messages and PR titles should be prefixed with a standard code the states what kind of change it is. They fall broadly into 3 categories: FEAT (feature), BUG (bug), and SUPP (support). The SUPP category has some more fine-grained aliases that you can use, such as BLD (build), CI (continuous integration), DOC (documentation), TST (testing), and RLS (releases).

Maintainer's Guide

Maintainers generally perform two roles, merging PRs and making official releases.

Merging PRs

We have a CLI script that will merge Pull Requests automatically once they have been reviewed and approved. See the help message in dev/ for full details. If you have two-factor authentication turned on in Github, you will have to generate an application-specific password by following this guide. You will then use that generated password on the command line for the -P argument.

Access the Ibis "Merging PRs" wiki page for more information.


Access the Ibis "Releasing" wiki page for more information.