Starting a new company in 2020, with a whole new stack, is a really interesting opportunity for me to look back over the last 20 years of my career with web software and make the right decision for my company.

And, I went with the most radical decision– which is to ignore "sexy" / "hype" technologies almost entirely, and go back to a stack that I first used over 15 years ago.

For my purposes, we are building a video streaming platform, where I wanted rapid customer-facing feature development, high testability, simple scaling, and ease of hiring great, experienced talent. To be clear, our web platform is NOT responsible for handling the actual bits and bytes of the video itself, that's an entirely different stack. It simply needs to manage the business rules and the customers experience of the video content.

I reviewed a lot of different technologies, but none of them seemed to fit the bill as well as Rails did! The hype train had long left the station with Rails, and the community is a little more sparse than it was previously. And, to be honest, Ruby was the language that was easiest for developers, but I find that most languages out there have adopted many of it's innovations for ease of use – or at least corrected their own.

Even with all of that, Rails still seems like the best framework for developing web applications that are no more complex than they need to be. And that's key to me, because it's very easy to go use React and Redux and GraphQL and a whole host of AWS Lamba's to power my blog... but you simply don't actually NEED that.

There are two choices I made in our stack that were new for me personally, and very different than what I would have chosen even 5 years ago.

1. Postgres - I decided to switch from MySql to Postgres for this project. I wanted to use UUID's instead of numeric primary keys, and knew I'd have a couple places where better JSON/object support would be key. Mysql remains far more popular, but almost every developer I respect has switched and preferred Postgres with a strong passion. It's not "sexy" but it's considered "better".

2. Stimulus.js - This was definitely the biggest and wildest choice to make. Stimulus is a Javascript framework by my old friend Sam Stephenson (Prototype.js, rbenv, turbolinks) and DHH, and it is a sort of radical declaration that your Javascript in the browser can be both powerful and modern AND simple. It leans heavily on the belief that HTML-is-good and that data-* attributes are good. It focuses on the actions and interactions and not on the rendering aspects. It took me a while to wrap my head around, and I still have to remind myself, that server-side-HTML is how you solve many problems with this stack, and avoid trying to re-render things just in the browser. So far, I'm happy with this choice, but it is definitely a radical departure from the current trends.

In the past few months, a project we're working on grew up quite fast. Since we're adding more and more features, I'm considering migrating my Express/TS REST API towards a more solid and more "enterprise-like" framework. Since I am experienced with TypeScript but not so much with Rails nor Play (Scala), I'd like to have some advice on which one could provide the best development experience, and most importantly, the smoothest paradigm transition from the JS/TS world. I've worked on some personal project with Rails, but I've found the Ruby language really distant from what the TypeScript ecosystem and syntax are, whereas on the opposite - during the brief tours I've taken in the past weeks - it's been a pleasure coding in Scala. Obviously, there are some key differences between the two languages - and the two frameworks consequently - but despite all the ROR automation and ease of use I don't despise at all Scala's pragmatic and great features such as static typing, pattern matching, and type inference. So... Please help me out with the choice! Regards

If software performance is your top priority, then Scala/Play is probably best. If developer productivity is your top priority, then Ruby on Rails is the best choice in my opinion.

The Rails framework is batteries-included. The framework takes care of many things by default so that you don't have to. Logging, security, etc. It's also well-integrated; for example, controllers understand models out of the box. I had a better experience with RoR than with Play.

On the other hand, Scala and the JVM are more performant in general, so they can scale to serve more requests per second on the same hardware.

If you're considering serverless functions, then Scala is probably a better choice because it would be faster to load, giving you better economics.