General principles

Please read this first!

Explain what you’re doing and why.
Document new code with doc comments.
Include clear, simple tests.
Break work into digestible chunks.
Take the time to pick good names.
Avoid non well-known abbreviations.
Control and consistency over 3rd party code reuse: Only add a dependency if it is absolutely necessary.
Every dependency we add decreases our autonomy and consistency.
We try to keep PRs bumping dependencies to a low number each week in each component, so grouping dependency bumps in a batch PR is a valid option (see component’s README.md).
Don’t reinvent every wheel: as a counter to the previous point, don’t reinvent everything at all costs.
If there is a dependency in the ecosystem that is the “de facto” standard, we should heavily consider using it.
More code general recommendations in main repository CONTRIBUTING.md.
Ask for any help that you need!