What are your thoughts about the future of Ruby on Rails and Ruby in general? Does it make sense to transition to Ruby or learn Ruby in 2018/2019, and what are your thoughts about the performance of Ruby? I'm a PHP guy who started delving into Ruby world recently, and I must say the performance difference between PHP and Ruby cli apps is really noticeable, e.g. rails commands are a lot slower than php artisan.
For my thoughts on the current/future situation of Ruby and Rails, please see my answer above, I don't want to repeat all of that here.
If you are looking for a new language to supplement/replace PHP then Python is a great choice. Apart from good web frameworks (Flask, Django etc.) it has a ton of data science and machine learning libraries, can be used for embedded systems programming with MicroPython etc. If your focus is purely on web you could do much worse than looking into Elixir and Phoenix, I think we'll see a lot more demand for that over the next few years.
Re performance: I have very little experience with PHP, but from 5.2 onwards Rails includes Bootsnap by Shopify, which significantly speeds up application load time. As for the "Ruby doesn't scale" trope, I'm honestly getting a bit tired of it. Pure startup time is pretty irrelevant for long running backend applications and I've seen way too many people complain about Ruby's performance as a language when their apps had much bigger performance problems like non-optimized images, non gzipp-ed responses, no CDNs, unindexed/badly indexed databases, not using fragment/russian-doll caching etc. I can recommend Rails Speed by Nate Berkopec if you're ever getting serious about properly optimizing Rails applications.
Thanks for the thorough reply :)
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