A few days ago I wanted to re-install Sid Meier's Civilization III on my machine and play it again. This blog post is a summary of the tricks I had to use to make it work it work well; I am writing it down for posterity, maybe someone else will find it useful. That someone might even be future me.
For the past few weeks I have been working on a little side project, a library of Common Lisp bindings to cmark, the CommonMark reference implementation: cl-cmark (GitHub mirror). CommonMark is a dialect of Markdown which aims to remove any ambiguity, clean up the language specification and provide a common dialect of Markdown for other projects to use. The cmark library is the reference implementation for parsing CommonMark. It is written in C, so creating bindings for other language is fairly simple.
A web application typically consists of three layers: the frontend, the backend, and some sort of database system for persistence. While developing the frontend we often need to send messages to the backend, receive some response and process that response. Faking backends in automated tests is a solved problem, but sometime we don't want to write tests, we want to wildly experiment with various inputs as we are trying out the frontend by hand. We want to intercept messages and look into what is being transmitted. In this post I will demonstrate a simple fake backend using the mitmproxy application.