Stable, incremental, and additive is my personal theory about what underlies effective software practices. I’m pleased to find these qualities hold up quite well for practices described by Code That Fits in Your Head.

Code That Fits in Your Head seeks to collect scattered effective practices into a clear picture of effective software development. It is a fantastic read and I highly recommend it

A quick recap of stable, incremental, and additive

  • Stable: existing work is rarely effected by changes in other units of work
  • Incremental: value can be delivered in small and complete chunks
  • Additive: the chunks don’t just replace each other, the value adds up over time

These ideas permeate the practices from Code That Fits in Your Head

  • Fractal architecture: Refactor out a complete sub-concern as a unit of code exceeds a set complexity. Promotes a hierarch of similarly a system that is is a semantically clear and bite-sized in any given component. The system is fractal because any focused and low-complexity component may be make up of similarly focused and low-complexity components.
  • Walking skeleton: create the minimal deployable stack and deploy it so successive work can also be easily be deployed in incremental units.
  • Small & complete commits: Source control and commiting small self-contained units of work is foundational to the book’s development flow
  • Drivers: use defined motivations (TDD, BDD, complexity, etc) to initiate each change in the code and clarify when that unit of work is complete
  • Multiple-daily code reviews: lean into continuous integration and review code multiple times a day. Keeps reviews focused and small while pressuring for frequent complete units of work.
  • Strangler: New and refactored code exist side-by-side until the new approach replaces the old. Keeps code in a stable state while refactoring progresses incrementally.

The book also leverages idea’s I’ve previously identifies as stable, incremental, and additive. This includes

  • Continuous Integration / Continuous Deployment
  • Hexagonal Architecture / Ports and adapters
  • TDD, Red-Green-Refactor