* Rails is opinionated software. It makes the assumption that there is a "best" way to do things, and it's designed to encourage that way - and in some cases to discourage alternatives. If you learn "The Rails Way" you'll probably discover a tremendous increase in productivity. If you persist in bringing old habits from other languages to your Rails development, and trying to use patterns you learned elsewhere, you may have a less happy experience. * Don't Repeat Yourself: DRY is a principle of software development which states that "Every piece of knowledge must have a single, unambiguous, authoritative representation within a system." By not writing the same information over and over again, our code is more maintainable, more extensible, and less buggy. * Convention Over Configuration: Rails has opinions about the best way to do many things in a web application, and defaults to this set of conventions, rather than require that you specify every minutiae through endless configuration files.

* ThreadSpotter far surpasses simply collecting raw performance data – instead, it identifies, classifies and instructs the developer in ways to remove specific issues. * ThreadSpotter offers a solid, detailed understanding of performance problems to allow a quick resolution on the system under examination. It also models other execution environments and provides performance optimization guidance for other systems. * ThreadSpotter models thread communication and interaction effects, giving advice on how to resolve the resulting performance issues.