My tech stack progression:

Started with PHP without any frameworks, using a homegrown MVC architecture. Used to use `mysql_` functions everywhere. And only jquery + vanilla CSS in the front end.

Then moved to use PDO functions in PHP and Backbone.js + Less CSS in the front-end.

Then moved to Django in the back-end. Did not like Django very much as it is too opinionated and not flexible (although it's damn good for rapid development if you buy into their type of things).

Then moved to Flask + SQLAlchemy and using a home grown architecture. This is a sweet spot for me in terms of back end and stayed in this spot for the longest time.

Moved to Postgres from MySQL as I fell in love with Postgres.

Then learnt React+Redux. Liked it. Made most sense to front-end development this way. Moved front-end stack to React+Redux.

Learning Haskell and been working with Scotty and eyeing Servant for a while now.

Let's see where it goes from here.

PS: this is my personal journey through various tech stacks in various products at various companies I have worked. I'm not talking about moving a product through these many tech stacks. That doesn't make any sense.