I've written an article describing the Web architecture that we use at the MEMS Exchange. Comments and suggestions on it are very welcome. http://www.amk.ca/python/writing/mx-architecture/ Abstract: The MEMS Exchange (MX) project is an experiment in distributed microfabrication that needs to take advantage of the Internet in order to function. In developing the required custom software, the MX software development team faced a complex task with no clear way to figure out our requirements ahead of time. The team therefore selected or wrote tools that are simple yet still powerful and flexible, and also adopted a flexible and free-flowing methodology using some of the principles of agile programming. This paper will discuss the tools we've built and the techniques we use. --amk