There are a lot of web services was written.
For last 8 years I'm writing in Python. During this period I've successfully finished a lot of projects. Most of them are web applications based on Django, Pyramid, Pylons or Tornado frameworks. Some projects are the collections of scripts for various process automation. My experience is limited by back-end development. But I have strong business relationships with experienced front-end developers so we can build high quality modern web applications.