It's mostly C++ or Java (& other JVM languages) in high class finance, some python and verilog for their niches. The article is about the odd one out firm that

It's mostly C++ or Java (& other JVM languages) in high class finance, some python and verilog for their niches. The article is about the odd one out firm that has its own rather unique stack. It essentially says so at the end - "[you] become less employable anywhere else".