An article on safety-critical, with a contribution of Nuno Silva (who works for CRITICAL):
https://increment.com/documentation/the-complex-world-of-life-saving-safety-critical-software/
Quoting:
"Most of the programs you use every day, from word processors to smartphone apps, need oversight to ensure their usability and security, no matter how much planning and testing went into their production. For the narrow slice of systems and software that lives depend on, dubbed “safety-critical,” the requisite oversight comes alongside strict government, industry, and trade organization-mandated standards that prove the software is safe to use in high-stakes applications.
Today, software deemed safety-critical controls very complex hardware, from medical devices and cars to aircraft and nuclear reactors. Safety-critical software has unique requirements in each field, some of which are more regulated than others, but in general, regulatory agencies require extensive documentation to help ensure that the software is certifiably safe. This can equate to many times more documentation—including fastidious risk management documentation—than a comparably sized consumer software might need, given the extensive planning and testing that safety-critical software must undergo to meet certification standards. Through this documentation, teams must prove that their software is safe to use and has a very, very low chance of endangering human life."
(...)
"Safety-critical regulators have been slow to welcome emerging technologies and methodologies that are prevalent in the wider tech industry, like agile software development. Myklebust and his colleague Tor Stålhane wrote a book, The Agile Safety Case, that lays out how teams using agile development can meet compliance requirements and satisfy safety-critical standards assessors. Their plan limits the number of documents that need to be revised when updating software, which would speed up the process considerably. In the railway industry, where Myklebust primarily operates, it might take six months from writing the last line of code on a project to when it’s implemented on a track or signaling system; he reckons it should only take a week or so."
