megmorsie uses CodeIgniter
I used CodeIgniter while working at KHM Travel Group. It was the system we used for an affiliate-based site called TravSearch, which I later replaced with a WordPress Multisite. I developed a .csv upload form to transfer all the information from the affiliate table of CodeIgniter to the user and options tables in WPMU.
SpreadServe uses Tornado
SpreadServe's RealTimeWebServer is built in Tornado. Spreadsheets loaded into SpreadServeEngine instances are projected into browsers using Tornado. Server side recalcs are pushed to the browser using web sockets.
gllona uses CodeIgniter
CodeIgniter is the MVC framework used for the PHP coding. Also, validation criteria for (database) table fields are the provided by CodeIgniter, and signatures for others are derived from those.
papaver uses Tornado
setup an api for a client with tornado backend. incredibly fast and lightweight. unfortunately breaks down when using third party libraries which block internally.
delbin uses CodeIgniter
It is super easy to do things in PHP using codeigniter. Used the MVC architecture to create different types of pages and modules.
Banyan uses Tornado
Tornado with Async/Await coroutines provided in Python 3.5 make up for an excellent stack for a micro-service.
Kalibrr uses Tornado
We use Tornado as our websockets server, using SockJS (an alternative to socket.io).