docs: added simple CONTRIBUTING.md

CONTRIBUTING.md

@@ -0,0 +1,41 @@
+# Contributing guidelines
+
+First of all, welcome and thanks for showing interest to improve this library! Any contribution is welcome.
+
+## Issues
+
+- Feel free to ask any kind of related questions
+- When reporting bug, please provide as much information as possible, ideally with minimal reproducible example
+- When requesting feature, document why do you need it, for finding optimal solution, and also requested usage/example
+of new feature is welcome as well as different approaches to solve the problem
+
+## Writing code
+
+This lib aims to be lightweight and minimal, so try to avoid unnecessarily introducing new variables and complex computations,
+that will eventually need to be removed in the cleanup release. Because of [semver](https://semver.org/), every new feature (addition to API)
+has to be kept at least until major release. So, if you are not sure about your code, please open an issue and discuss it first.
+
+## Committing
+
+- Use [conventional commits](https://www.conventionalcommits.org/en/v1.0.0/)
+- Don't create commit history pollution, e.g. 15 commits the with same name for 1 feature
+
+## Testing
+
+For now, this lib is missing automated testing, so please test your code manually before creating, and also compare new behavior
+with old behavior of this lib, so you can at leas partially see, whether you change did not create any side effects.
+
+## Documentation
+
+Please keep documentation up to date. If you are adding new feature, please also add it to the documentation. If your feature
+will not be documented, your PR can be still merged, but your feature may be undocumented for some time.
+
+## Creating PR
+
+- If PR is related to issue, please link it to it
+- One feature/fix pre PR, "fix: preventing adding feature A, feat: A" is ok, "feat: A, fix: unrelated fix" is not ok
+
+## Releasing
+
+After your PR is merged, it will be released standalone or batched along with other changes. For now, only author (@hejtmus) can do release,
+but feel free to ask for immediate release if you need it.