Tbh mate I think this is a bit of a daft contrarian take. Clearly you would offer it to existing employees to see if anyone was interested then, if not, hire ne

Tbh mate I think this is a bit of a daft contrarian take. Clearly you would offer it to existing employees to see if anyone was interested then, if not, hire new employees like I said in the comment. If you've still failed to find an employee (who is going to get paid to do nothing but learn a brand new language and then be senior dev/tech lead for it which would be a pretty sweet gig for a lot of people) you would then do the heavy handed approach of forcing an employee to learn it. At the end of the day you can't have a critical piece of organisation infrastructure completely unmaintained and if you have to, then you'll have to strong arm someone in to it, but you should always aim to do that as the complete last resort. And if you are going to do it, you can probably sweeten the deal with a pay rise or other perks. But I seriously don't think you'd have to because if you were a junior/intermediate dev and someone offered you an opportunity like this to both learn a new language whilst getting paid and rise a rank in position and compensation you'd be mad not to take it.