The original title is "Testing LLMs Like Software: A Promptfoo Deep Dive for QA Engineers"

Short summary

A practical guide to using Promptfoo for production-grade LLM testing, covering versioned evals, deterministic assertions, and CI gates. It argues traditional QA breaks on non-deterministic LLM outputs and shows how to pin model versions, use built-in assertion types, and write custom JS/Python checks. The article promotes a paid handbook but includes substantial runnable code and real workflows.

• •LLMs break deterministic QA assumptions — correctness must be redefined for probabilistic outputs
• •Pin model versions in config to prevent silent regressions from vendor updates
• •Use deterministic assertions first (JSON validation, latency, cost) before resorting to judge models

Generated with AI, which can make mistakes.