Inform 7 is now open source
Inform is a design system for interactive fiction based on natural language, and consists of a core compiler, together with extensions, kits and other resources, a number of outlying tools, and documentation, along with applications presenting the system in a friendly way on MacOS, Windows and Linux. This software had been used extensively since 28 April 2006, but by 2016 its source code was in considerable need of modernisation. In…