Designing for recovery [software design]

How should you design your software to detect, react, and recover from exceptional conditions? If you follow Jim Shore\´s advice and design with a fail fast attitude, you won\´t expend any effort recovering from failures. Shore argues that a "patch up and proceed" strategy often obfuscates problems. Shore\´s simple design solution is to write code that checks for expected values upon entry and returns failure notifications when it can\´t fulfil its responsibilities. He argues that careful use of assertions allows for early and visible failure, so you can quickly identify and correct problems