The Economic Stack

The Map

Ten crates carry the dedicated economy responsibilities. Six more are supporting crates that the economy crates depend on for identity, oracles, anchoring, and discovery.

Dedicated Economy Crates

Each crate has one primary responsibility.

The settlement and market layer has grown three receivable-side primitives, all landing in chio-credit rather than a new crate: obligation atoms and factoring (chio_credit::obligation and chio_credit::factor), a clearinghouse netting round (chio_credit::clearing::compute_netting_round), and streaming payment channels over a single ChioEscrow deposit. The invariant that makes them safe to compose is one immutable obligation atom per unit of value, so no second economic claim can be minted for the same value.

chio-metering ships two budget layers that coexist. BudgetEnforcer is the flat per-grant enforcer scoped by session, agent, or tool. BudgetTree is the entry point to hierarchical governance: it models organizational structure (organization → department → team → agent) where every node carries its own caps and window and draft spend is checked against every ancestor. The tree does not replace the enforcer; the enforcer stays per-grant while the tree renders a fail-closed BudgetDecision from a caller-supplied SpendSnapshot. Both are storage-agnostic.

Supporting Crates

Six crates provide identity, discovery, oracle, and anchoring types that the dedicated economy crates compose.

• chio-did: self-certifying did:chio identifiers and DID Document resolution. Method-specific identifier is the hex form of an Ed25519 public key. Types: DidChio.
• chio-credentials: Agent Passport verification. Native canonical-JSON-signed bundle with an OID4VCI projection derived from the native record. Types: AgentPassport, PortableReputationCredential, CertificationCredential.
• chio-link: oracle integration for cross-currency conversion (Chainlink, Pyth), sequencer health, circuit breakers. Produces canonical OracleConversionEvidence. Types: ChioLinkOracle, ExchangeRate.
• chio-anchor: checkpoint anchoring over EVM root-registry, Bitcoin super-root with OpenTimestamps, Solana memos, and multi-lane proof bundle verification.
• chio-listing: generic registry namespace, listing, and trust-activation records with search and admissibility APIs. Types: Listing, SignedListingPricingHint, ListingSearchResponse.
• chio-open-market: bidding and ask-response API built on the listing registry and governance charters. Types: SignedBidRequest, SignedAskResponse, SignedAcceptedBid.

Where Each Layer Talks to the Kernel

The kernel signs receipts. Every economy crate either hands the kernel something to admit or consumes the receipts it emits.

Trust Boundaries

Not every crate is inside the trusted computing base. The kernel and a small set of supporting libraries are. The rest are operator-replaceable.

Inside the TCB

• chio-kernel: the only component that signs receipts and runs the guard pipeline.
• chio-core and chio-core-types: canonical JSON, crypto primitives, and the receipt and capability types every other crate consumes.
• chio-manifest: the kernel relies on its signature verification to admit tool servers.
• chio-metering: cost metadata flows through here on the way into signed receipts.

Operator-replaceable

• chio-link, chio-anchor, chio-settle: oracle, anchoring, and settlement adapters. Operators pick the backend; the kernel verifies embedded evidence instead of trusting the implementation.
• chio-appraisal, chio-underwriting, chio-credit, chio-market, chio-autonomy: pricing, policy, instruments, coverage products, and bounded automation. Replace the operator's book without touching the kernel.
• chio-federation, chio-listing, chio-open-market: bilateral policy, discovery, bidding. The kernel recognizes the record schemas; a buyer can skip them.
• chio-reputation, chio-credentials: deterministic scoring and passport issuance. These crates are outside the TCB.

Reading Order by Use Case

The crates compose, but you do not need to read them in dependency order. Pick by what you are building.

• Provider: chio-manifest, chio-listing, chio-metering. See Manifests and Pricing.
• Buyer: chio-credentials, chio-open-market, chio-settle. See Passports and Discovery.
• Insurer: chio-underwriting, chio-credit, chio-market. See Underwriting, Credit Facilities, Liability Market.
• Operator: chio-federation, chio-anchor, chio-settle. See Bilateral Federation and Operating.

Version and Stability

The economy crates ship from the same workspace as chio-kernel and follow the same release rhythm. Schema identifiers are versioned per record type. A few examples from the source:

pub const EXPOSURE_LEDGER_SCHEMA: &str = "chio.credit.exposure-ledger.v1";
pub const CREDIT_SCORECARD_SCHEMA: &str = "chio.credit.scorecard.v1";
pub const CREDIT_FACILITY_REPORT_SCHEMA: &str = "chio.credit.facility-report.v1";
pub const CREDIT_BOND_REPORT_SCHEMA: &str = "chio.credit.bond-report.v1";
pub const CAPITAL_BOOK_REPORT_SCHEMA: &str = "chio.credit.capital-book.v1";

pub const TOOL_MANIFEST_SCHEMA: &str = "chio.manifest.v1";

Schema strings are stable identifiers. A bump from v1 to v2 means a breaking change. Each signed record carries its schema identifier so consumers can refuse versions they do not recognize.