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CONTRIBUTING.md

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+# Contributing to torchgpipe
+
+torchgpipe is currently under development. We will try to make it stable and
+usable. Until v0.1.0, which will be our first production release, we don't open
+up receiving issues or pull requests. Please wait for a while.
+
+Kakao Brain, the project owner, has authority to update this guide.
+
+## Boundaries
+
+torchgpipe is a library, not an experiment.
+
+The `torchgpipe` Python module, which is the `torchgpipe` folder in this
+respository, has responsibility to provide GPipe for CUDA in PyTorch, and
+options with some trade-offs which users have freedom to choose. It would not
+accept any requirement beyond the original GPipe implementation.
+
+The "torchgpipe" project, which is this repository itself, has responsibility
+to make GPipe easy-to-use by deep learning researchers or engineers. It
+provides handy resources and documentation for the best practice.
+
+Delicate reproduction of experiments in GPipe paper is out of the
+responsibility of this project.
+
+After we release v0.1.0, if your pull request is accepted, we will merge it by
+squashing regardless of the work history. Your forked repository should keep
+the history.
+
+## Styleguides
+
+- Think of readability, consistency, simplicity, and cohesion.
+- Don't put spaces around an operator if it is easier to read
+  (`2*i + 1` not `2 * i + 1`.)
+- Lint by mypy and Flake8 with our `setup.cfg`.
+- Format code by autopep8 and isort with our `setup.cfg`.
+- Prefer PyTorch's coding style rather than PEP 8 (`input` is a good name for
+  input tensors.)
+
+## Development
+
+### Unit Testing
+
+To run unit tests, you can simply run `python setup.py test`. But if you want
+to use advanced testing options, run pytest manually:
+
+```sh
+$ pip install pytest
+$ pytest
+```
+
+For example, you can filter tests by name:
+
+```sh
+$ pytest -k 'test_gpipe'
+```
+
+### Code Quality
+
+We use mypy and Flake8 to check code quality:
+
+```sh
+$ pip install mypy flake8
+$ mypy .
+$ flake8 torchgpipe tests setup.py
+```
+
+We highly recommend to use autopep8 and isort to follow the coding style
+automatically:
+
+```sh
+$ pip install autopep8 isort
+$ autopep8 -ir torchgpipe tests setup.py
+$ isort -rc torchgpipe tests setup.py
+```