A programming language is a medium of expression.

Paul Graham

Neither of us intended to develop with IronPython, least of all write a book on it. It sort of happened by accident. In 2005 a startup called Resolver Systems[1] set up shop in London. They were creating a spreadsheet platform to tackle the myriad problems caused in business by the phenomenal success of spreadsheets. The goal was to bring the proven programming principles of modularity, testability, and maintainability to the spreadsheet world—and having an interpreted language embedded in Resolver One was a core part of this. As Resolver One was to be a desktop application used by financial organizations, it needed to be built on established and accepted technologies, which for the desktop meant .NET.

At the time the choice of interpreted language engines for .NET was limited; even IronPython was only at version 0.7. The two developers who comprised Resolver Systems[2] evaluated IronPython and discovered three important facts:

2 Giles Thomas, who is CEO and CTO, and William Reade, a hacker with a great mind for complex systems.