I’m not sure if it counts as “major”, but there’s Io. http://iolanguage.org/1Justen RobertsonRichard Kenneth EngFeb 27, 2016·1 min readYou’re not sure??? Io is as far from mainstream as it can be! For a 13-year-old language, it’s outside of the Top 50 at TIOBE. At langpop.corger.nl, it’s essentially at the bottom of the list, just barely registering!