- Multithreading. "It sounded like a good idea," according to the article, but it just leads to a myriad of thread-managing tools, and "When they don't work, it's pure chaos. The data doesn't make sense. The columns don't add up. Money disappears from accounts with a poof. It's all bits in memory. And good luck trying to pin down any of it..."
- NP-complete problems. "Everyone runs with fear from these problems because they're the perfect example of one of the biggest bogeymen in Silicon Valley: algorithms that won't scale."
The other dangerous corners include closures, security, encryption, and identity management, as well as that moment "when the machine runs out of RAM." What else needs to be on a definitive list of the most dangerous "gotchas" in professional programming?