See also my blogpost on wrapper^low-level API
Compare to laymen on the street, I have accumulated fairly deep, specific and demonstrable non-local expertise in two lucrative field i.e. software dev + finance
- concurrency details (theory++) in real languages
- dStruct choices and effective combinations
- dStruct implementation details in java/c++/pyhton
- SQL joins and tuning
- sockets? no deep insight but my expertise beats most peers
- Most standard algo problems are familiar to me
- memory models, memory layout.. beneath c++ and java
- drv pricing math, VaR statistics, bond math. My expertise goes beyond the degree
These trophies are won based on TSN, interviews and personal time investment … not automatically
— Let me focus on low-level vs high-level
Most of the dev expertise domains are low-level, consequently very specific — you either know it or don’t. I can even teach in these subjects. The more low-level, the rarer is the expertise. The laymen developers have a vague idea of the low-level details, for many reasons.
High-level understanding is often more useful (than low-level, theoretical QQ knowledge) in projects, but in job interviews, low-level knowledge is differentiator.
Practically all (98%) high-end java/c++ interviews use low-level questions as differentiator. I excluded the start-ups as I’m unfamiliar with them… Eg: Quoine.
In my dev (not system architect) interviews, they rarely asked high-level stuff like spring rationale, design patterns…
I tend to believe these questions can’t /separate the crop from the chaff/
The finance dnlg also serves as differentiator among developers. The most specific sub-domains are quant math, the “architecture” and some of the jargon.
C++ is more low-level than java; java is more low-level than python…
Q: Paradoxically, C and assembly are even more low-level but not more valuable?
%%A: Some C knowledge is highly valued. For example, kernel knowledge is high-value and mostly at the level of C, compiler, assembly, and hardware
%%A: assembly expertise in device drivers or embedded is not really relevant to HFT, and too far from the money
MOM is not low-level and seldom asked.