tl;dr:"In this post I argue that integration-vs-unit is a confused, and harmful, distinction. I provide a more useful two-dimensional mental model instead. The model is descriptive (it allows to think more clearly about any test), but I also include my personal prescriptions."
tl;dr:It takes 2x more time to write a patch if you are unfamiliar with the project, but 10x more time to figure out where to change the code. "ARCHITECTURE.md is a low-effort high-leverage way to bridge this gap." Aleksey gives us an example.
tl;dr:Although a Rust advocate, Aleksey argues the reasons not to use the language - you don't "ultimate performance" or control over hardware resources, it's complex, has a slow compile time, and more.