Formal Assurance Kernel (FAK)

A minimal proof substrate that formally verifies the correctness of autonomous governance stack components through deterministic, replayable, machine-verifiable proofs.

Overview

FAK serves as a kernel-level verification system beneath DIO, ZT-AAS, ICAE, and POC. It consumes immutable artifacts from these systems and attaches formal proofs to them, ensuring behavioral soundness, authority non-escalation, economic invariance, and semantic preservation.

Architecture

┌─────────────┐ ┌──────────────┐ ┌─────────────┐ ┌─────────────┐
│     DIO     │ │   ZT-AAS     │ │    ICAE     │ │     POC     │
│ (Execution) │ │(Capabilities)│ │   (Cost)    │ │  (Policy)   │
└──────┬──────┘ └──────┬───────┘ └──────┬──────┘ └──────┬──────┘
       │               │                │               │
       └───────────────┴───────┬────────┴───────────────┘
                               ▼
       ┌───────────────────────────────────────────────┐
       │       FAK - Formal Assurance Kernel           │
       │                                               │
       │  ┌─────────────┐       ┌─────────────┐        │
       │  │ Invariant   │       │   Proof     │        │
       │  │ DSL         │       │   Engine    │        │
       │  └─────────────┘       └─────────────┘        │
       │           ▲                   ▲               │
       │           └─────────┬─────────┘               │
       │  ┌──────────────────┴─────────────────────┐   │
       │  │         Artifact Manager               │   │
       │  │    (Content-addressable storage)       │   │
       │  └────────────────────────────────────────┘   │
       └───────────────────────┬───────────────────────┘
                               │
                               ▼
       ┌───────────────────────────────────────────────┐
       │                 Verifier                      │
       │       (Standalone verification tool)          │
       └───────────────────────────────────────────────┘

Components

Invariant Specification DSL

Minimal language for declaring invariants, preconditions, postconditions, and temporal properties. Avoids general-purpose computation by design.

Proof Engine

Combines trace replay with invariant checking using SMT-style reasoning where required. Produces deterministic, replayable proof witnesses.

Artifact Manager

Ensures immutability, content-addressability, and versioning of all inputs. Artifacts are uniquely identified by content hash.

Verifier

Standalone tool that accepts proof bundles and re-checks invariants without runtime dependencies. Performs integrity checks to ensure content-addressability and prevent tampering.

Build

cargo build --release

Test

cargo test

Run

./fak # Linux/macOS

.\fak.exe # Windows

Design Principles

1. Deterministic - All proofs are reproducible with identical inputs.
2. Replayable - Proofs can be re-executed without external dependencies.
3. Machine-Verifiable - Proofs compile to verifiable intermediate representations.
4. Content-Addressable - Artifacts are immutable and uniquely identified.
5. Minimal DSL - Invariant language avoids general-purpose computation.
6. Explicit Failures - Clear counterexamples on invariant violations.

Requirements

• Rust 1.56+