SonarQube is described as 'Open source quality management platform, dedicated to continuously analyze and measure source code quality, from the portfolio to the method. Static code analysis vailable in the "Community Edition" (free / open source) for:' and is an app in the development category. There are more than 25 alternatives to SonarQube for a variety of platforms, including Windows, Web-based, Linux, Mac and SaaS apps. The best SonarQube alternative is Codacy. It's not free, so if you're looking for a free alternative, you could try Codacy or Shellcheck. Other great apps like SonarQube are Coverity Scan, SlowQL, Flawfinder and SAST Online.
Measure evaluation of the code quality over time.