Great article detailing the software and software engineering practices powering the space shuttle:
But how much work the software does is not what makes it remarkable. What makes it remarkable is how well the software works. This software never crashes. It never needs to be re-booted. This software is bug-free. It is perfect, as perfect as human beings have achieved. Consider these stats: the last three versions of the program — each 420,000 lines long-had just one error each. The last 11 versions of this software had a total of 17 errors. Commercial programs of equivalent complexity would have 5,000 errors.
Given, the process is onerous, but the SEI scale correctly captures today's current level of process:
Software may power the post-industrial world, but the creation of software remains a pre-industrial trade. According to SEI's studies, nearly 70% of software organizations are stuck in the first two levels of SEI's scale of sophistication: chaos, and slightly better than chaos.