Design a system that records events in a single globally consistent order across many machines.

The distributed ordering problem that sits at the heart of Kafka, replicated logs, and consensus systems. Interviewers look for you to face the uncomfortable fact that physical clocks lie, then pick the right instruments: a single sequencer, consensus, or logical clocks. This walks that progression.

Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.