Direct link to extension (the site just gives you more context): https://chromewebstore.google.com/detail/sphinx-earn-your-di...
Philosophically it's a speed bump rather than a hard gate, because you'll eventually tear a gate down but you'll leave a speed bump. I've always eventually removed site blockers, or just had them become a nuisance that I reflexively dismiss before getting to distracting sites. Site blockers don't really reduce the "start navigating to a distracting site" muscle memory, and they eventually just become annoying. Dopamine is a hell of a drug.
At the same time, I've been getting frustrated that my intermediate/advanced math skills have atrophied, and becoming more senior in my career (plus AI...) has caused my coding skills to atrophy even further. Realistically I'm not going to force myself to do math or coding exercises after dinner, I'm an adult with other adult things to do. So this is a compromise where I can set up the practice problems in a place where I know I'm going to go.
So I built an extension where the gate (/punishment) requires you to do some math, solving both problems at once. There's no data transmitted off of your client, no subscriptions, and the permission to view sites is only used for the (obvious) reason of blocking them.
Thanks for checking it out!