Earlier today @jonathoda tweeted this enjoyable blog post, Your Debugger Sucks [1], which references the Pernosco debugger [2]. I'm familiar with omniscient debuggers like Chronomancer, but this is the first I've heard of Pernosco, and it seems very neat. Omniscient debuggers take a step beyond time travel debugging, allowing instant exploration and comparison of program state across time. The video on the home page gives a sense of Pernosco's UI (not great), but the About page is what I found most interesting — a very cleanly written and compelling articulation of their vision, and a taste of what we've all been missing. [1] https://robert.ocallahan.org/2019/11/your-debugger-sucks.html [2] https://pernos.co

Yeah! This point specifically is 💯

Traditional debuggers have an notion of "the current point in time" that is tied to heavyweight internal state (typically a set of running processes). In Pernosco, "the current point in time" is still a useful UI concept (we call it the focus), but it is merely a parameter to queries to our omniscient database, so we can change it freely and instantly.