The game code for Blight is written in Python and hosted on Google App Engine and uses standard web page serving technology.
Basically, every time you request the game page, and then every time you submit an order, the save game is loaded out of the database, the change applied, and saved back to the db. A report is written which is basically just a json file of everything in the game and send back to the client.
The game client is written in plain javascript, but I have some quite unusual ways of doing because I’m not a huge fan of HTML and CSS so everything is written in javascript.
Feel free to ask questions if you want to know more.