The Economic Stack

The workspace keeps its economic code in one directory, crates/economy/, which holds 16 members. Several crates the Economy pages document are not among them: identity, passports, reputation and federation live under crates/trust/, and the tool manifest lives under crates/platform/. Both groups are listed below, with the workspace path each one carries in the root manifest.

The economy directory

Every crate below sits at crates/economy/<name>. Each carries a narrow public API and its own Cargo.toml, and the one-line purpose is that manifest's own description expanded against the crate's README or module documentation.

Economy crates in other directories

These five carry types the Economy pages cite constantly, and none of them sits in crates/economy/. The path column is the one the root manifest lists.

The shared vocabulary sits below all of them. chio-core-types (crates/core/chio-core-types) names no other workspace crate in its dependencies, and it defines the capability, receipt, and canonical-JSON types every crate here consumes. chio-core sits one level up and is where the economy reaches the rest of the system.

Which of them the kernel names

The dependency direction is settled by the manifests, and it runs the opposite way from the record flow in several places. crates/kernel/chio-kernel/Cargo.toml lists five members of crates/economy/ as direct dependencies:

• chio-appraisal
• chio-credit
• chio-link
• chio-settle
• chio-underwriting

Most of the others reach it through chio-core, which re-exports the domain crates under one chio_core::* import path, so the kernel reaches them by naming chio-core alone. The ten crate re-exports sit between lines 17 and 43, interleaved with the module re-exports of chio-core-types:

pub use chio_appraisal as appraisal;
pub use chio_autonomy as autonomy;
pub use chio_credit as credit;
pub use chio_federation as federation;
pub use chio_governance as governance;
pub use chio_listing as listing;
pub use chio_market as market;
pub use chio_open_market as open_market;
pub use chio_underwriting as underwriting;
pub use chio_web3 as web3;

Two members of crates/economy/ sit outside that closure entirely. chio-anchor depends on chio-kernel rather than the other way round, so it sits above the kernel and publishes what the kernel has already signed. Nothing in the kernel's dependency graph reaches chio-metering; the only crate that depends on it is chio-data-guards.

An interchangeable backend is swapped behind a trait, not by dropping a crate dependency. PriceOracle is declared in chio-link/src/lib.rs:248 and implemented there by ChioLinkOracle at :790. The kernel holds it as Option<Box<dyn PriceOracle>> and takes whichever implementation the operator installs through set_price_oracle. A kernel with no oracle installed holds None.

The receivable side inside chio-credit

Three receivable-side primitives land 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.

Two budget layers inside chio-metering

BudgetEnforcer evaluates a single policy scoped per session, per agent, or per tool. BudgetTree expresses organizational structure, organization to department to team to agent, where each node has its own caps and window and draft spend is evaluated against every ancestor. The tree does not replace the enforcer: the enforcer stays per grant while the tree is per organization, and the tree renders a fail-closed BudgetDecision from a caller-supplied SpendSnapshot. Neither owns storage. Callers read the snapshot from whatever backing store they use and pass it to BudgetTree::evaluate.

Schema identifiers

Every signed record carries its schema identifier, versioned per record type, so a consumer can refuse a version it does not recognize. A bump from v1 to v2 is a breaking change. Five of them from the credit crate:

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";

See also

• Building a provider: Manifests for chio-manifest, Pricing for the metered models, and Discovery for chio-listing.
• Buying: Passports for chio-credentials and Open Market for the bid, ask and accept records.
• Underwriting and capital: Underwriting, Credit Facilities, and Liability Market for chio-underwriting, chio-credit, and chio-market.
• Operating a peer: Bilateral Federation for chio-federation and Operating for the settings behind them.
• One transaction through these crates: the procurement tour, which cites each crate where it acts.