Was able to correctly guess it's about Therac-25 from title alone. I can't help but think this specific story is being overtold, while other software-related accidents doesn't get enough attention.

Software controlling a safety-critical equipment doesn't even need a bug to cause deaths, bad user interface can do it just fine. "Behind Human Error" gives an example of device used to assist a surgery, that required complicated procedure to set up, which had a step unrelated to device functions in context and was easy to forget (rendering the device non-functioning) and would not indicate in any way it wasn't working when it was expected to. As for a more modern example, many of recent aviation accidents involve pilots failing to correctly interact with cockpit systems.

In the Therac-25 case the core issue (leaving aside procedures put in place to prevent the exact thing) was an error in the code, that could eventually be found and corrected, but software with badly designed interface can kill people while working exactly per specification, shifting the blame on the operator.