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README.md

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+# HOOMD-blue component template
+
+`hoomd-component-template` provides a framework to develop a component that extends
+[HOOMD-blue](https://glotzerlab.engin.umich.edu/hoomd-blue/).
+
+It includes:
+
+* CMake scripts to build the component.
+* Template C++ and Python modules.
+* An example unit test.
+* Pre-commit configuration.
+* GitHub Actions configuration.
+
+## Building the component
+
+To build this component:
+
+1. Build and install HOOMD-blue from source.
+2. Obtain the component's source.
+    ```
+    $ git clone https://github.com/glotzerlab/hoomd-component-template
+    ```
+3. Configure.
+    ```
+    $ cmake -B build/hoomd-component-template -S hoomd-component-template
+    ```
+4. Build the component.
+    ```
+    $ cmake --build build/hoomd-component-template
+    ```
+5. Install the component.
+    ```
+    $ cmake --install build/hoomd-component-template
+    ```
+
+Once installed, the template is available for import via:
+```
+import hoomd.template
+```
+
+## Creating a new component
+
+To create a new component:
+
+1. Fork the [hoomd-component-template](https://github.com/glotzerlab/hoomd-component-template/)
+    repository.
+2. Add C++ and Python files to `src/`.
+3. Address all TODO comments. These explain how to set your package name, add C++ files, add unit
+    tests, and other tasks. Use [ripgrep](https://github.com/BurntSushi/ripgrep) to find all TODO
+    messages:
+    ```
+    $ rg TODO . .github
+    ```
+4. Add unit tests in `src/pytest` using [pytest](https://docs.pytest.org).
+5. Format and check code style with [pre-commit](https://pre-commit.com/).
+    ```
+    $ pre-commit run --all-files
+    ```
+6. Push your changes to GitHub and the provided [GitHub Actions](https://docs.github.com/en/actions)
+    workflow will run and test your that your code compiles on the CPU (with and without MPI), and
+    on the GPU (with and without MPI). The workflow also runs the unit tests on the CPU. You should
+    run GPU unit tests locally, GitHub does not provide free GPU runners for GitHub Actions.
+
+## Maintaining your component
+
+The HOOMD-blue developers will periodically update
+[hoomd-component-template](https://github.com/glotzerlab/hoomd-component-template/), including
+updates to the GitHub Actions workflow, pre-commit configuration, and CMake scripts. Merge these
+changes into your fork to to test with the latest version of HOOMD-blue.
+
+For example, run:
+```
+$ git remote add upstream https://github.com/glotzerlab/hoomd-component-template
+$ git fetch upstream
+$ git merge upstream/trunk
+```
+and resolve merge conflicts as appropriate.
+
+## Documenting and releasing your component
+
+TODO: Document your component in `README.md` (this file).
+
+When appropriate:
+
+* Add [Sphinx](https://www.sphinx-doc.org) documentation and publish it on
+[readthedocs](https://www.readthedocs.org).
+* Add a [conda-forge](https://conda-forge.org/) package.
+* Announce your component on the [hoomd-users](https://groups.google.com/g/hoomd-users) mailing
+  list.