Yes open source projects do, and Kinto is currently a well supported project at Mozilla.  The folks who made Kinto are awesome, and do awesome things at Mozilla, but my personal experience from working at Mozilla is that Mozilla is an awesome steward of open source projects for <i>users</i>.  The devtools team is doing a much better job of becoming stewards of tools for developers, but Mozilla has traditionally been less than ideal steward of projects for use by third parties.