Pieter Levels' minimalist approach to software deployment contrasts sharply with the robust quality assurance (QA) process at Lago, a company that builds billing infrastructure products. While Levels favors rapid deployment without staging servers, Lago emphasizes rigorous QA due to the complexity and potential financial impact of its product, which involves intricate billing processes. Lago's QA involves detailed specifications, technical tests, and synchronous reviews by the product team to ensure that all scenarios are considered and that the product behaves as expected. This process includes merging code with the main branch for more realistic testing and a staggered release strategy to minimize risks. Lago's approach, which significantly reduces errors in production, is tailored to its high-impact product needs and offers insights for other companies seeking to improve their QA processes.