A few years ago I solved 200 LeetCode problems and still froze on Mediums I hadn't seen. The breakthrough wasn't another hundred problems. It was a different loop. A problem asks for the longest substring with at most K distinct characters. You've solved sliding window before. Maximum sum subarray of size K, done. Longest substring without repeating characters, done. This third one stalls you. Twe
I'm a fullstack web developer with 6 years of experience. Python, Rust, JS, databases, and APIs. That's my day job. I had never touched electronics. A few weeks ago, I decided to build CyberKey. The itch came from something boring at work: my VPN disconnects when I lock my computer, and I have to type a TOTP code several times a day. Unlock my phone, open the authenticator app, read the code, type