Boids
15 January 2024
One of the things I love about natural systems is how complex behavior can arise from sets of simple rules. In biology you see this fairly often, for example Lotka-Volterra equations predict predator-prey interactions and can lead to very complex outcomes despite being incredibly simple. A famous example from the history of computer science is John Conway’s Game of Life which produces incredibly complex (and sometimes unpredictable) interactions between cellular automata from only four rules. A lesser known example are Boids, or bird-oid objects, which demonstrate how three principles, separation, alignment, and cohesion can explain how flocking behavior can arise despite decentralized control. I implemented my own version of the Boids algorithm in Typescript using the HTML5 Canvas element. The complete code can be found in the Github repo.
Whitebox vs. Blackbox Testing
04 June 2023
Many blog posts on testing belabor the need for “pure functions” that will always return the save value given the same inputs and never have any side effects. While this is nice to have, it is rarely achievable in real code bases that need to do IO operations or deal with third-party APIs. Even when it is technically achievable, it can be impractical. Instead, developers should aim for “blackbox” testing based entirely on inputs when possible, and “whitebox” testing, which “peeks” into the implementation, when it is not.
