VC Dependency Trees and Lifecycle Hooks

Managing Nested Credential Logic, Governance Transitions, and Execution Readiness Through Structured Dependencies

5.9.1 Why VC Dependency Management Is Critical

NSF operates in highly composable, interdependent systems, where:

• A disaster response credential may depend on simulation forecast validity

• An operational credential may be granted only if a training credential is valid

• Legal credentials may expire or escalate based on treaty enforcement clauses

• DAO governance decisions may trigger mass credential expiration or elevation

To support these dynamics, NSF introduces:

• VC Dependency Trees: Formal graphs defining preconditions for credential validity and use

• Lifecycle Hooks: Triggerable logic points that govern issuance, escalation, deprecation, and audit propagation

This enables automated governance, jurisdictional compliance, and precise control over machine-mediated authority.

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5.9.2 VC Dependency Trees: Concept and Structure

A VC Dependency Tree is a directed acyclic graph (DAG) where:

• Each node is a Verifiable Credential

• Edges represent “depends on” relationships

• Validity of the root VC is contingent on all required child paths being satisfied

Example (simplified):

             DisasterResponseVC
              /             \
   TrainingCredentialVC  SimulationRunVC
                             |
                  SimulationModelVC

The tree expresses that DisasterResponseVC is only valid if:

1. The holder completed training

2. A valid simulation run occurred

3. The model used in the simulation is itself credentialed

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5.9.3 Encoding Dependencies in Credential Metadata

Each VC can include a depends_on field:

{
  "id": "DisasterResponseVC#0x772e",
  "depends_on": [
    "TrainingCredentialVC#0x994c",
    "SimulationRunVC#0x73af"
  ]
}

Dependencies can reference:

• Specific credential IDs

• Credential types (e.g., “any ForecastModelVC issued by DAO X”)

• Clause hashes or simulation outputs

Credential Oracles and Clause Runtimes resolve and validate these dependencies at execution time.

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5.9.4 Types of Dependencies

Dependency Type	Description
Temporal	“Must be issued within 30 days of SimulationRunVC”
Scope-limited	“Only valid if dependent VC is for same jurisdiction”
Threshold-based	“Requires two or more ForecastModelVCs to validate risk class”
Escalation-linked	“Becomes valid only if EmergencyTriggerVC is activated”

Each dependency path is cryptographically verifiable and governed by policy clauses or DAO-defined rules.

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5.9.5 Lifecycle Hooks: Definition and Function

Lifecycle Hooks are programmable events within the credential lifecycle:

Hook	Trigger	Result
on_issue	When VC is created	Link to clause ID, emit onboarding notice
on_use	When VC is used	Log usage, notify DAO, trigger reward or alert
on_expiry	When VC expires	Trigger revocation VC, notify holder
on_revoke	When revoked	Invalidate dependents, emit governance event
on_dependency_fail	When a child VC becomes invalid	Suspend parent VC automatically

These hooks allow NSF to behave like an event-driven operating system for credentials.

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5.9.6 Example Lifecycle Hook Configuration

"lifecycle_hooks": {
  "on_issue": "log_to_registry",
  "on_use": "update_usage_counter, notify_DAO",
  "on_expiry": "revoke_and_notify_holder",
  "on_dependency_fail": "flag_for_review, suspend_if_unused"
}

These hooks can execute:

• Smart Clause logic

• Governance scripts

• Oracle calls

• DAO voting workflows

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5.9.7 Cascading Revocation and Audit Propagation

If a VC in a dependency tree is revoked:

• All dependent VCs are:

  • Flagged as “suspended”

  • Prevented from execution use

  • Marked in Audit Layer

• DAO receives alert

• Credential Oracles emit a dependency_failure notice

• Reissuance pathways may be offered (if clause-bound)

Example:

Revoking ForecastModelVC#0x33aa invalidates 11 SimulationRunVCs and 38 DisasterResponseVCs.

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5.9.8 Visualizing and Querying Dependency Graphs

The Credential Registry and Audit Layer expose APIs and UIs to:

• Render credential dependency DAGs

• Search for unresolved, circular, or risky chains

• Run diagnostics on:

  • Depth of dependency

  • Number of affected policies

  • Recency of dependency validation

Example query:

find all active DisasterResponseVCs dependent on SimulationRunVCs older than 90 days

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5.9.9 Lifecycle Event Signing and Zero-Knowledge Compatibility

All hooks and dependency events:

• Are cryptographically signed

• Can be included in ZK proofs (e.g., "I used a VC that had no revoked dependencies")

• Are auditable by DAOs and governance entities

• Support delayed disclosure for sensitive contexts

Credential Oracles help embed these events into ZK-compatible attestation flows.

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5.9.10 Dependency Management as Institutional Logic

In NSF:

• Credential issuance is no longer a one-off event

• It becomes a programmable trust contract

• With:

  • Pre-conditions

  • Execution hooks

  • Real-time dependencies

  • Governance-bound escalation paths

This enables modular, traceable, and enforceable governance at scale—with no need for centralized policy enforcement.