Design a knowledge-graph-backed question answering system.
Some questions need precise multi-hop facts that vector retrieval cannot chain. The signal is entity linking plus query translation over a graph (or GraphRAG), and knowing when the graph is worth its maintenance cost. Here is the design.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
Some questions need precise multi-hop facts that vector retrieval cannot chain. The signal is entity linking plus query translation over a graph (or GraphRAG), and knowing when the graph is worth its maintenance cost. Here is the design.
Lead with where the obvious approach breaks, because that is the judgment they are screening for — most candidates jump straight to the happy path and lose the room.
Then walk the failure back through the pipeline in order, naming the one metric the customer's exec sponsor actually cares about before you propose the fix.
