Huh, I think I finally found a BFT Consensus algo that I really like and is actually simple. Other ones that say are simple, are not, while I think this one I would be able to implement myself if needed: Simplex.

There’s a paper with pseudo-Pascal, but it is actually quite easy to follow. And on top of it there’s a website explaining it in even simpler terms.

https://simplex.blog

What I like about it:

• actually simple to understand - I’d say simpler than Raft,
• partial-synchrony not a problem for me,
• works for any number of peers,
• fast finality (in network latency terms),
• logically atomic commits: there is no “submitted, but still pending reaching consensus” stuff,
• there’s a Go implementation that should clarify anything unclear: https://github.com/ava-labs/Simplex