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Volatility-based decomposition is an architectural design method that identifies axes of change and encapsulates them behind stable module boundaries to reduce blast radius. It distinguishes sequence volatility from activity volatility to guide boundary placement.

To identify axes of change, analyze your codebase for sequence volatility and activity volatility, then name boundaries based on the specific volatility they encapsulate. This ensures module interfaces remain stable while isolating internal fluctuations.

Yes, volatility-based decomposition suits architectural reviews of module and service boundaries across codebases of varying sizes and team structures. It evaluates existing decompositions to ensure abstractions properly isolate volatility.

Sequence volatility refers to changes in the order of operations, while activity volatility involves changes to the operations themselves. Evaluating both helps determine optimal boundary placement to encapsulate distinct rates of change.

Ensure stable interfaces by explicitly naming the axis of volatility a boundary encapsulates and verifying that internal changes do not propagate outward. This keeps service contracts stable while managing internal fluctuations.

Avoid volatility-based decomposition when axes of change cannot be clearly identified or when module boundaries do not require strict volatility isolation. It provides the most value during structural reviews where reducing blast radius is critical.