Fitness Functions Matrix
An architectural fitness function provides an objective integrity assessment of one or more architectural characteristics. Fitness functions may be automated or manual; this matrix deliberately covers only the automated subset.
The horizontal axis is scope: atomic checks one characteristic, while holistic checks a combination and the trade-offs between characteristics. The vertical axis is cadence: triggered runs on an event, continual runs persistently; temporal checks sit outside this simplified 2×2.
The matrix shows coverage and cadence. A holistic example should test interacting qualities—such as security and latency under load—rather than merely crossing a service boundary.
List the architectural qualities the system must preserve.
For the automated subset, classify scope as one characteristic or a combination with trade-offs, then cadence as triggered or continual.
Find an empty cell and add a check that actually measures the intended quality or trade-off.