ACI family · the bridge · built on the duality engine

ContinuityCTY — the bridge of the validated substrate

HACI and MACI are not two formats that convert into each other. They are two faithful exits of one validated substrate. Validate the substrate first; then both skins must exit together — each recovering the substrate exactly, graph and all.

the correction — nothing crosses except through the substrate

EXIT H · human
HACI-C
the document. carries provenance in a visible tail so it is lossless.
S
validated
first
EXIT M · machine
MACI
the message stream. JSON, refs explicit, the causal DAG.

skin → from → [ SUBSTRATE ] → to → skin. The old eskimo seam was H failing to be a faithful exit: it rebuilt refs as linear adjacency, so M→H→M silently collapsed any non-linear graph. Continuity closes it — and proves the closure by re-opening it on demand (the toggle below).

the six continuity properties

C1substrate-valid — the pivot is a well-formed causal DAG
C2bridgeable — machine-only roles detected, never dropped
C3faithful-H — from_H(to_H(S)) = S
C4faithful-M — from_M(to_M(S)) = S
C5co-exit agree — both skins emit the same S
C6round-trip both — H→M→H and M→H→M are identity

the live bridge — write the substrate, watch both exits

human exit: carry refs
EXIT H · HACI-C

      
EXIT M · MACI

    

    

    

  

  
Flip the switch to drop refs in the human exit — exactly the eskimo regression. Watch C6 M→H→M turn red: the machine's ref-graph re-rendered into HACI-C and back no longer matches, because the human skin threw the refs away. That is the seam, and that is why the engine's mutation test demands a catch.


  
the chain — continuity across time

  
The suite proves the conversation survives the crossing between skins; the chain proves it survives the crossing between versions. Each substrate is sealed into a canonical manifest, signed (Ed25519, the who), timestamped against an external RFC-3161 authority (the when), and linked to its predecessor by prev_root. The anchor points outside the repo; the verifier recomputes everything.


  

    engine status · reproduced locally:
    suite 14021/14021
    FSS 12/12
    BSS 7/7
    mutation caught
  


  

    two-layer honest. The continuity cost is real and visible: to make the human skin a faithful exit, HACI-C carries id|from|authority|role|refs in a tail — base HACI traded that away for cleanliness and bought the seam. The machine-only roles (DECISION / DELEGATE) cannot exit as H at all, so C2 detects them as non-bridgeable residue rather than dropping them. The suite is exhaustive seeded property-testing, not a formal proof; HACI-C content is single-line here, multi-line / CODE-fence bodies a declared extension. This page runs the ported engine logic in your browser; the authoritative engine is the Python that ships in the repo.
  


  

    CONTINUITY · CTY · 2026-06-26
    David Lee Wise · Bridge-Burners LLC · built on the duality engine