====== 20 Best Practices ====== 
  - **Correctness**, **simplicity** and **clarity** come first.
  - Avoid unnecessary **cleverness**. If you must rely on cleverness, encapsulate and comment it.
  - Avoid duplication ([[http://en.wikipedia.org/wiki/Don't_repeat_yourself|DRY]]).
  - Coupling and Cohesion. Systems should be designed as a set of cohesive modules as loosely coupled as is reasonably feasible.
  - Data hiding. Minimize the exposure of implementation details.
  - Minimize the scope of variables, pragmas, etc..
  - Establish a rational error handling policy and follow it strictly.
  - Interfaces matter. Once an interface becomes widely used, changing it becomes practically impossible (just about anything else can be fixed in a later release). Design the module's interface first.
  - Design interfaces that are: consistent; easy to use correctly; hard to use incorrectly; easy to read, maintain and extend; clearly documented; appropriate to your audience. Be sufficient, not complete; it is easier to add a new feature than to remove a mis-feature.
  - Write components that are testable in isolation.
  - The result of every file operation or API call or external command should be checked, and unexpected results handled.
  - Use descriptive, explanatory, consistent and regular names. [[en:devmon:guidelines:variables|(see variables)]]
  - Avoid magic numbers.
  - Don't optimize prematurely. Benchmark before you optimize. Comment why you are optimizing.
  - Agree upon a coherent layout style and automate it. [[en:devmon:guidelines:tidy|(see tidy)]]
  - Adopt a policy of zero tolerance for warnings and errors. Tools such as Perl::Tidy and Perl::Critic can help here.[[en:devmon:guidelines:tidy|(see tidy)]]
  - Commenting: prefer to make the code obvious; don't belabor the obvious; comments describe what and why not how.
  - Separate user vs maintainer documentation.
  - Use a revision control system [[https://github.com/bonomani/devmon]] and single-step automated build/test.
  - **"Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live"** (Damian Conway)