Compare LoRA, prefix tuning, prompt tuning, and adapters. How do PEFT methods differ?
PEFT is a family, not only LoRA, and interviewers test whether you know how each one injects trainable parameters. The signal is where each method adds capacity and the latency and quality tradeoffs that result.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
PEFT is a family, not only LoRA, and interviewers test whether you know how each one injects trainable parameters. The signal is where each method adds capacity and the latency and quality tradeoffs that result.
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.
