The vertical component is about efficiency. It's very hard to get past a certain point with a general purpose OS and Golang. You'll need NCPU threads/processe

The vertical component is about efficiency. It's very hard to get past a certain point with a general purpose OS and Golang. You'll need NCPU threads/processes and no context switching, so you're definitely talking about: - unikernel or user-land NIC driver and network stack - async/await or continuation passing style to reduce the per-client/request memory footprint I'm not applying though, but I'm saying that "Golang + super-efficient" is definitely not something I'd assign as an interview weekend project -- that's something to be discussed in detail during the interview, and I'd expect no more than a horizontally scalable solution over a weekend. Getting the vertical efficiency tuning done will take a lot of time and cannot be expected to be a weekend or week project by an unpaid applicant, but you can expect the applicant to tell you how they'd go about it.