Governance is a social layer, but execution must be mathematical. I built Arkheionx to enforce strict state transitions on Safe treasuries before and after transaction execution. A multisig approval, governance vote, or signer quorum does not prove that a transaction is safe; it only proves that humans or delegated systems approved it. Arkheionx treats execution as a deterministic state machine: unsafe transitions such as delegatecall execution, guard mutation, module mutation, owner mutation, fallback handler mutation, unlimited approvals, gas refund abuse, unknown target execution, malformed calldata, and native value drains are rejected by policy before they touch treasury state.
The architecture separates immutable enforcement from controlled mutability. ArkheionxGuard and ArkheionxModuleGuard form the immutable core firewall around Safe transaction and module execution paths. PolicyRegistry and AdapterRegistry provide timelocked configuration surfaces for policies and risk adapters, with adapter registration bound to explicit codehash pinning and quarantine logic. This lets me scale coverage without hiring an operational team: new risk classes are handled by deploying stateless adapters, queuing them through a delay, binding them to exact selectors and codehashes, and letting the immutable guard enforce the result. The core does not need to mutate every time the threat surface expands.
The proof layer is executable. I built a Foundry invariant suite that models an adversarial Safe environment and repeatedly attempts malicious transitions through the real checkTransaction and checkAfterExecution lifecycle. The handler attacks guard removal, module guard mutation, fallback handler mutation, module mutation, owner mutation, unlimited approvals, delegatecalls, gas token refunds, custom refund receivers, massive native gas refunds, zero-target calls, malformed calldata, unknown calls, and native value drains. Arkheionx survived 512,000+ adversarial calls with zero ghost violations. I rely on deterministic fuzz campaigns, invariant counters, and reproducible traces as the foundation of security validation; manual audit is additional scrutiny, not the only line of defense.