I'm investing in the F# safe stack. So far it's amazing how quickly I can build something. It's also amazing how clean and readable I can get the code. But I feel like there is a horrible mess of complexity just under the hood. If any of the amazing maintainers choose to stop my app has it's legs cut off.

That said I've found that with every other project I've worked on. I still maintain a B2B sales site on PHP 5.4 with Zend 1.1. There is no hope of migrating that anytime soon. Ironically that has no J's framework. The front end is such a mess and will never get the funding to clean up.

I think building with tools that allow such a great developer experience might be worth it. However F# makes it hard to find developers to maintain it in the future.

I hate the lack of longevity in our industry. I work with 30 year old CNC machines that are still supported by their manufacturer. I can't wait until our field gets that mature.