I've been working on BareAgent lately. It's meant for small teams and ppl who generally self-host their apps and manage their containers.
The idea is that a small (<10mb Golang agent binary | around 20mb ram) reads frequently the server metrics and docker container metrics and filters logs for filter words like fatal, panic and web based errors like 500 etc. and gives alerts in various ways.
Another cool feature is that it learns your base levels of CPU / RAM usage over 2 weeks and checks pulses against those and send alerts if they keep staying outside that range.
So it's basically metrics + alerts + basic incident management for your severs.
It has a free tier and I'd love some feedback.