Sunflower Editor is a prototype for a next-generation code editor that takes "printf debugging" further than ever before: see the value of every variable, on every line, in realtime as your code runs. It is a sort of antithesis to the idea that type-safety and compile-time checking will set us free; instead, visibility into our programs will. On the backend, the editor uses a custom AST transformation that is designed to be extremely fast (it can run with every keystroke) and not significantly impact performance (the additional code is both lightweight and is optimized by the JIT compiler like any other code). It is functional enough that https://art.sunflower.industries was in fact designed in this editor. Oh, and it also supports collaboration via WebRTC.