Add contributing document

.github/pull_request_template.md

@@ -12,7 +12,7 @@ If you find mistakes in the documentation, please submit a fix to the documentat
 
 <!-- Please tick if the following things apply. You… -->
 
-- [ ] read the [CONTRIBUTING guidelines](README.md#contributing)
+- [ ] have read the [CONTRIBUTING.md](./CONTRIBUTING.md) file
 - [ ] raised a GitHub issue or discussed it on the projects chat beforehand
 - [ ] added unit tests
 - [ ] added integration tests

CONTRIBUTING.md

@@ -0,0 +1,34 @@
+# Contributing
+
+Headscale is "Open Source, acknowledged contribution", this means that any contribution will have to be discussed with the Maintainers before being submitted.
+This model has been chosen to reduce the risk of burnout by limiting the maintenance overhead of reviewing and validating third-party code.
+
+## Why do we have this model?
+
+Headscale has a small maintainer team that tries to balance working on the project, fixing bugs and reviewing contributions.
+
+When we work on issues ourselves, we develop first hand knowledge of the code and it makes it possible for us to maintain and own the code as the project develops.
+
+When code is contributed to the project, it is typically a positive thing. People enjoy and engage with our project, but it also comes with some challenges; we have to understand the code, we have to understand the feature, we might have to become familiar with external libraries or services that this new feature integrates with and it needs to be reviewed from a security perspective. And that is only when it comes to reviewing it. After the code has been merged, the feature has to be maintained, meaning that changes to external parts need to be updated, and kept working.
+
+The review and the day-1 maintenance adds a significant burden on them maintainers. Often we hope that the contributor of the feature will help out, but we found that most of the time, they disappear when they have their new feature added.
+
+This means that when someone contributes, we are mostly happy about it, but we do have to run it through a series of checks to establish if we actually can maintain this feature.
+
+## What do we require?
+
+A general description is provided here and an explicit list is provided in our pull request template.
+
+All new features have to start with a design document that has to be discussed in the issue tracker (not discord) with a use case for the feature, how it can be implemented, who will implement it and what the plan for maintaining it is.
+
+All features have to be end to end tested (integration tests) and have good unit test coverage to ensure that they work as expected, and work as expected over time. If the change cannot be tested, a strong case for why this is not possible needs to be presented.
+
+The contributor must help maintain the feature over time, if a feature is found to be left unmaintained, we will have to remove it.
+
+## Bug fixes
+
+Headscale is open to code contributions for bug fixes without discussion.
+
+## Documentation
+
+If you find mistakes in the documentation, please submit a fix to the documentation.

README.md

@@ -95,15 +95,7 @@ The maintainers work together on setting the direction for the project. The unde
 
 ## Contributing
 
-Headscale is "Open Source, acknowledged contribution", this means that any
-contribution will have to be discussed with the Maintainers before being submitted.
-
-This model has been chosen to reduce the risk of burnout by limiting the
-maintenance overhead of reviewing and validating third-party code.
-
-Headscale is open to code contributions for bug fixes without discussion.
-
-If you find mistakes in the documentation, please submit a fix to the documentation.
+Please read the [CONTRIBUTING.md](./CONTRIBUTING.md) file.
 
 ### Requirements