For a short while, 14 years into my own career, I managed to shift from my Windows-oriented .NET development role into an organisation which did PHP against a s

For a short while, 14 years into my own career, I managed to shift from my Windows-oriented .NET development role into an organisation which did PHP against a strong Linux environment. I got the job after demonstrating my expertise at a local programming meetup, by doing a presentation on design patterns (a transferrable skill), and convincing the employer I was keen to learn PHP, how my existing skills could be related to it, and recently-introduced aspects of the language that resonated with me (i.e. PHP with strong object-oriented style, using constructs that were recently-introduced at the time). If I had stuck it out there, it's possible I could have built up my skillset further in that direction and transitioned into another area that was more low-level and appealing. The lesson from that is, I think, that you can do a 'stepping stone' approach that is only a few degrees removed from what you do already, each time you transition jobs. Do that a few times, build up some contacts within the new network of people you will meet during that in order to broaden further opportunities, and you may well succeed in a meaningful transition in the medium-term.