AAT/SFT Research Notes

AAT / SFT Interface

A one-way bridge from local algebra to field-shaped evolution.

AAT provides the local algebra of architecture objects, operations, invariants, witnesses, signatures, and theorem boundaries. SFT uses that algebra as a premise for bounded software-evolution models without making AAT depend on SFT.

Dependency direction

The dependency is fixed: AAT does not depend on SFT; SFT depends on AAT. AAT remains an independent mathematical theory of local architecture structure, while SFT reads selected AAT concepts as architecture projections, observable coordinates, local transition premises, and admissibility boundaries.

Direction of dependency
AAT -> SFT

AAT provides local algebra.
SFT uses that algebra to make software evolution computable.

Translation rules

Interface terms are mappings, not redefinitions. SFT may use AAT vocabulary as local premises and observation axes, but SFT trajectory, forecast, policy, and feedback concepts remain SFT concepts.

  • ArchitectureObject Read in SFT as the architecture projection of a field state.
  • ArchitectureOperation Read as a local law premise for an accepted or proposed transition.
  • InvariantFamily Read as a constraint family the field attempts to preserve.
  • ObstructionWitness Read as a selected unsafe, costly, or blocked trajectory coordinate.
  • ArchitectureSignature Read as a partial coordinate system for observing trajectories.
  • Theorem boundary / non-conclusions Read as the claim boundary that SFT forecasts and governance reports must not cross.

Forbidden readings

The interface exists to prevent accidental claim promotion. Local architecture facts do not become global software-history facts merely because they are useful premises in an SFT model.

  • AAT lawfulness Do not read it as future trajectory safety.
  • AAT measured zero Do not read it as safety for unmeasured axes.
  • AAT operation preservation Do not read it as global policy safety.
  • SFT ForecastCone narrowing Do not read it as global risk reduction.
  • ArchSig extraction Do not read it as a ground-truth architecture object.
  • SFT forecast Do not read it as a Lean theorem.

ArchSig bridge

ArchSig is neither AAT nor SFT. It is the observation and reporting layer that maps real repository artifacts into AAT observables and SFT field estimates with explicit measurement status, coverage, warning, and non-conclusion boundaries.

Observation bridge
real artifacts
  -> ArchSig
  -> AAT observables
  -> SFT field model

ArchSig output can guide review and forecasting work. It does not strengthen an AAT theorem or make an SFT forecast into a theorem.

Canonical sources

This page summarizes the interface for the public site. The repository document remains the authoritative statement of the mapping tables, claim levels, and non-confusion rules.