Software runs the world, and there are two kinds: disposable code and durable code.

[Bernardo de La Paz]

6. Your insight about the distinction between durable and disposable code is a good one.

I'm familiar with both kinds but hadn't really thought much about that aspect.

One place they interact is in agile coding shops. In agile mode, one writes a lot of code and rewrites it and throws parts away that end up not needed and throws important parts away so they can be written again from scratch. Code should not be thought of as precious per se, but code that has survived multiple revisions and extensive testing has to be respected.

Disposable code is also applicable as a concept to bootstrapping a program (different from bootstrapping a computer, which is essentially one long run of the operating system program). Bootstrapping code is where you get bare-bones functionality working on grossly simplified versions of files and tasks. This gives you a few big things: 1) A working version that does something, however pitiful. 2) Greater understand of the task and the plan, 3) Basic scars and wounds from the first bugs encountered. Then you modify pieces of the code the make it do more things, deal with more events, and break less often.

The more code I write the more agile I find myself tending. Countering that, as the program grows, the more careful and tentative I become with making changes. There's a lot to be said to modifying a program bit by bit to keep it cohesive. But sometimes redesigns are needed to straighten out kinks in the code, reduce code smell, make it less brittle, and make it more understandable (and hence maintainable).