My definition of an expert in any field is a person who knows enough about what’s really going on to be scared.
—P. J. Plauger
Automated testing is an essential topic for anyone writing the kind of large-scale applications TypeScript was invented for. By automating the testing of the program, developers are able to spend more time on new features and less time fixing defects. No single method of testing provides a high enough defect detection rate and that means a combination of several kinds of testing is needed to detect a reasonable number of problems before the software is released.
It may be surprising, but ...