A project’s mission statement should outline its aims and values in a formal way. Fortunately, I don’t need to come up with anything particularly unique because some wise Rubyists have already identified something which has now become part of the very fabric of Ruby: MINSWAN.
Matz Is Nice So We Are Nice.
For me, that goes far beyond being welcoming of all people no matter who they are or what their background is. It echoes a fundamental principle of kindness, consideration and understanding, including of those who may, at times, appear not to be.
Remember that our community is diverse - possibly moreso than any other in the programming world (in part, because of this very philosophy) - so PLEASE try your hardest to be considerate of those who may be different to you, even if you don't understand them.
This works both ways. If you come across a person or opinion that leaves you dumbfounded, remember that everyone's opinions have developed in different ways. Perhaps the other person lacks the very particular experiences that you have been through. Or perhaps you are fortunate (or unfortunate) to have never experienced what they have experienced. Be understanding, be willing to give the benefit of the doubt, and try to enlighten rather than enrage and pointscore.
This, I suppose, is a roundabout way of saying that we intend to be a kind and considerate community of Rubyists