Could it perhaps be this? Interesting read about the level of effort and process invested in the Space Shuttle's software (~1996) [0] For a TLDR, this answer

Could it perhaps be this? Interesting read about the level of effort and process invested in the Space Shuttle's software (~1996) [0] For a TLDR, this answer [1] is great. My favorite excerpt: The Shuttle software consists of ca. 420,000 lines. The total bug count hovers around 1. At one point around 1996, they built 11 versions of the code with a total of 17 bugs. [0] https://www.fastcompany.com/28121/they-write-right-stuff https://www.fastcompany.com/28121/they-write-right-stuff [1] https://space.stackexchange.com/questions/9260/how-often-if-ever-was-software-updated-in-the-shuttle-orbiter https://space.stackexchange.com/questions/9260/how-often-if-...