Lessons from PromptLayer on Adapting LLM Evaluation Strategies

Evaluation engineering is just one step in the iterative prompting lifecycle. Unlike static tests, evaluations must evolve with the prompts they assess. This talk outlines how to adapt evaluation strategies—such as backtesting, regression testing, and even vibe-based testing—throughout the lifecycle of a prompt. Evals are just one of the many tools in the prompt engineering toolkit, and we will discuss when to rely on them and when to ignore them.