I did triage / performance consulting for a long time with several products in that space, added features to shipping commercial projects, and worked on a produ

I did triage / performance consulting for a long time with several products in that space, added features to shipping commercial projects, and worked on a product of my own in that space. While in theory you could build your own tool tailored to your specific organizational needs, I can't really say I'd recommend it. In fact, it wasn't completely uncommon for me to replace whatever homegrown tooling had been built with our kit because of scale, features, better UI / time to resolution tools, etc. If you are just doing some basic app logging, sure - roll your own if you want - but if you are trying to do real-time tiered analysis across something bigger than a few servers, there are commercial products that in this day and age are relatively cheap (or at least a lot more affordable than in the past)