Principles of good software design

Software design is a process of decomposition: breaking down large systems into manageable units for independent implementation.
To manage complexity: eliminate it by
- Avoiding special cases
- Or hiding complexity through modular design!
“Design it twice:” John advocates for this. For example when he designed the API for the Tk Toolkit: the second design proved superior.
Deep modules: creating deep modules with simple interfaces masks significant internal functionality. This helps manage complexity.
Error handling:
- The tactical approach is trying to "define errors out of existence" by designing systems to prevent certain errors from occurring. Be careful of simply ignoring necessary error checks though!
When designing interfaces: consider the caller's perspective
Design reviews and discussions: these are important to get more viewpoints and when evaluating design tradeoffs.
- John mentions a specific whiteboarding technique for achieving consensus in discussions – consider trying it out!