Thanks for your interest in evcc! Most ways to help don't need any code: answering questions, testing new versions, improving support for your own devices, translating or editing the docs. docs.evcc.io/en/contribute gives an overview of all ways to help and of the project's repositories.
The ground rules of the main repository apply to all evcc repositories. In short: start small, open an issue or discussion before a pull request, keep pull requests focused and in English, understand every change you submit and mark AI-generated text as such.
Setup, build and test instructions are in the README of each repository. General development topics are discussed on Slack.
By contributing, you agree that your contributions are licensed under the existing license terms that apply to the respective parts of the project.