I think you're expecting it to be something more exciting than it is (I was too at first.) It's just a front end for static analysis tools. Coala doesn't do any analysis on its own. Everything is delegated to other tools. It just provides a way to pass configuration in and to parse the output so you know what lines in the source file have problems.
Code Climate does something similar with their Engines[0] specification. Personally I like how they make use of Docker containers to perform the analysis. It is perhaps a bit heavyweight for simple analyses but it makes it really easy to install different language runtimes and tools.
Code Climate does something similar with their Engines[0] specification. Personally I like how they make use of Docker containers to perform the analysis. It is perhaps a bit heavyweight for simple analyses but it makes it really easy to install different language runtimes and tools.
[0] https://github.com/codeclimate/spec