Seravo
Seravo is a company with a strong commitment and expertise in Linux and open source software, with a long history of using and developing (e.g. doing packaging) of Debian and its derivates (e.g. Ubuntu).
They were offering the premier Linux support service in Finland until ca 2021 at linux-tuki.fi (archived at old.linux-tuki.fi) but the service has been discontinued.
The blog in English can be found at linuxnatives.net.