[mollmerx]

I think that's a very interesting question, to which the answer probably depends on how you define 'thrive'.

It seems unlikely to me that any language could become mainstream without being open source. The expectation that a compiler or interpreter should have its source available is only growing.

At the same time, kx's kdb+ is an example of a product that sits in a niche and has generated significant revenue despite being closed source. kdb+ has achieved this by primarily targeting financial services, which is a sector that's less sensitive to closed source than most, and is able to spend money on whichever product solves their problem.

If kerf manages to gain an edge over its competitors for a particular set of problems then sure, it can thrive in the long run the way kdb+ has.

[xixi77]

It could change in the future, but there are a plenty of languages that got pretty mainstream while closed source -- in terms of working with numbers and data, I'd definitely call matlab and sas mainstream, stata and mathematica are nearly mainstream, R of course is open source which is a huge reason for its popularity, but it's a clone of closed-source s+ which was fairly popular already. In the general-purpose world, c# and swift got most of their traction while still closed source, etc. Surely there are more examples in other domains... But yes, there is definitely a very welcome trend to open source stuff.