@jonathanhogg A quarter-century ago, we were developing a new version of JProbe, and as we got close to the day we had to send the golden master to the factory to manufacture CDs, we were short a settings configuration tool.
The team were told to skip the GUI editor and work on mission-critical features. Meanwhile, the program manager spent a weekend writing the editor in HyperCard, packaged with Metacard, a tool now known as LiveCode: https://en.wikipedia.org/wiki/LiveCode_(company)
We shipped it.