Saw this last week. The examples are limited but clearly easy to reproduce. I saw in a discussion on Reddit where it seems they plan to get even faster using more techniques like prefetch. https://news.ycombinator.com/item?id=22803504
I came across QuestDB in the past, but never tried myself. At my company, we use kx and onetick. Could you please elaborate why you are also comparing with Postgres since it's not really a time-series database nor revendicating to be part of the "high performance" club?
I don't think it's fair to say "A is faster than B" like in the above comments based on the order they appear in a list that mixes GPU clusters and laptops results. The author of the benchmark does nothing wrong deontologically, but the results table seems ordered by time and some people jump to quick conclusion or use it as a way to rank performance when it's not appropriate.
Greenplum seems to like a way to throw more hardware at a problem. Queries are too slow with postgres? Shard your data across machines and distribute queries to speed things up by running in parallel. It's using scale as a means to compensate for low efficiency.
On the opposite side of the spectrum you have other open source projects like questDB that have full focus on core performance: constantly optimise to get as much as possible from a single processor core. You can't scale out (at least yet), but given how fast it is on single core, it will be pretty powerful if they chose to go this route.
I am a big supporter of part time too. I can't overstate the importance of work-life balance. Work less, work better, and don't forget yourself nor your family.
However reading the description, I can't tell whether the potential hire fits this category.
Are they looking to have 2 jobs in parallel? What would their side thing be, is it different enough that they wouldn't be working on both concurrently?
If they want to be away from writing software 2 days a week to fulfill a hobby (e.g restore a boat, paint or whatever) then it makes a lot of sense. They will be happy, grateful, and the culture will be great.
If they are seeking part time in order to work for 2 startups or setup their own side business, then I'm not so sure.