Technically, #FOSS is _just_ a license, but it's also a culture (with some baggage).

#UXDesign is just a set of techniques that doesn't care if you're open or closed.

It's exhausting how many #FOSS advocates lecture me on how incompatible UX is to open development or that the culture is a delicate flower and I'm doing it wrong.

Things like user studies, user testing, journey maps, or design explorations are indifferent to your culture. They are powerful tools you can embrace or hide from.