Cheat sheetFND-03

Architecture Characteristics

Foundations / Architecture Characteristics

The -ilities: non-domain concerns that shape structure and drive success. Three families, explicit or implicit, composable — and you must limit the driving ones.

criteria
Qualifying criteriaNon-domain, influences structure, and critical/important to success. All three must hold.
families
Three familiesOperational (runtime: availability, scalability), structural (code: maintainability, testability), cross-cutting (security, accessibility).
implicit
Implicit vs explicitExplicit = stated in requirements; implicit = unstated but essential (availability, security).
limit
Limit the driversCharacteristics compete. Optimizing all yields a mediocre, over-complex design — pick a small handful.
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When stakeholders ask for 'everything', force a ranking. Identify the 3-7 driving characteristics and treat the rest as secondary.

Composite'Agility' = testability + deployability + modularity. Naming the composite hides three real drivers.
CompetitionPushing elasticity (in-memory grids) can hurt maintainability; hardening security can hurt performance.
Characteristic = non-domain + shapes structure + critical
Families: operational / structural / cross-cutting
Limit driving characteristics (~7 max); they compete
-ilitiesoperationalstructuralcross-cuttingtrade-offs
review in 6d