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
There's a moment every developer knows. You need to generate a PDF. It looks simple. You've done harder things. Three hours later, you're reading a Stack Overflow thread from 2016 that ends with "works on my machine." This post is about that moment — the actual options, what breaks in each, and where I landed after years of hitting this in production. It uses a stripped-down WebKit engine and conv