Skip to main content

No project description provided

Project description

CircleCI PyPI version


Shards tests based on a hash of their test name enabling easy parallelism across machines, suitable for a wide variety of continuous integration services. Tests are split at the finest level of granularity, individual test cases, enabling parallelism even if all of your tests are in a single file (or even single parameterized test method).


pytest-shard aims for simplicity. When installed, simply run:

$ pytest --shard-id=I --num-shards=N

where I is the index of this shard and N the total number of shards. For example, to split tests across two machines:

# On machine 1:
$ pytest --shard-id=0 --num-shards=2
# On machine 2:
$ pytest --shard-id=1 --num-shards=2

The intended use case is for continuous integration services that allow you to run jobs in parallel. For CircleCI, enable parallelism and then use:

pytest --shard-id=${CIRCLE_NODE_INDEX} --num-shards=${CIRCLE_NODE_TOTAL}

On Travis, you must define the environment variables explicitly, but can use a similar approach.


pytest-xdist allows you to parallelize tests across cores on a single machine, and can also schedule tests on a remote machine. I use pytest-shard to split tests across CI workers, and pytest-xdist to parallelize across CPU cores within each worker.

pytest-shard does not take into account the run time of tests, which can lead to suboptimal allocations. pytest-circleci-parallelized uses test run time, but can only split at the granularity of classes, and is specific to CircleCI.

Please open a PR if there are other promising alternatives that I have overlooked.


You can install pytest-shard via pip:

$ pip install pytest-shard


Contributions are welcome. Test may be run using tox.


This software is MIT licensed.

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

pytest-shard-0.1.2.tar.gz (3.6 kB view hashes)

Uploaded source

Built Distribution

pytest_shard-0.1.2-py3-none-any.whl (4.6 kB view hashes)

Uploaded py3

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page