Pros
The remote-only company, transparent & fair contracts, and stable company finances. Startup-alike atmosphere - you can do many things, and your efforts are visible and valued. You will never be bored here :) The team from the whole world. A lot of interesting projects and people. Altinity does services for different IT companies - you can also meet many IT people from different companies, switch between projects learn about dozen of different technologies used together with ClickHouse. So no matter which technology you want to learn next - in most cases 'it fits,' and you will get the opportunity to do some practical things with it, most probably in open-source. Also, there are many options to not be in shadow - you can participate in conferences, write blog articles, etc. It also does a lot of open-source stuff, so your work is often visible and makes the world a little bit better. Also, that means you can work with the open-source community.
Cons
Remote only company - there is no watercooler & office & coffee and other office things, which you got used to. Missing that a bit :) Chaotic a bit as any startup, and sometimes the number of things on my to-do list is too big. Sometimes it's hard for me to preserve work-life balance because there is always 'one more thing I want to finish today' (it's not a company policy of something, just a side effect of having a lot of things to research).