contract

Owned boundaries

Nautilus owns market and trading meaning; Anthera owns service metadata, durable projections, and browser contracts.

Question: Which types are allowed to become durable contracts?
Binding decision: Nautilus model values are canonical inside the runtime; infrastructure and browser shapes remain narrow projections.
Owner input: Exact target crate paths are reconciled against the Tradingview workspace in Phase 0.

Owned envelopeOwned boundaries

source: provider · dataset · schema · instrument
series: aggregation · step · price source · generation
time: event · receive · commit watermark
order: record identity · sequence · correction lineage
scope: tenant · entitlement · query budget
proof: coverage · completeness · exhaustion · provenance

External SDK and infrastructure types terminate outside this boundary.

The kernel dependency rule

The runtime composes core, model, live/node, Databento, trading, and IBKR at one revision. Data, system, portfolio, risk, and execution form the coherent kernel. QuestDB, Redis, workflow, and browser adapters depend outward from bounded Anthera projection ports.

Nautilus model → kernel → bounded projection ports
QuestDB, Redis, workflow, and browser adapters implement Anthera service ports
runtime and CLI own lifecycle, composition, and proof commands
every workspace crate inherits strict Rust lints

EvidenceARCHITECTURE.md and scripts/check-arch.sh.

The provider is already integrated

nautilus-databento uses Databento's official Rust client and supplies file loading, historical requests, live subscriptions, a LiveMarketDataClient, DBN decoding, and Arrow/catalog support. Anthera validates that adapter instead of building another normalization path.

DBN schema coverage, symbology, timestamps, precision, and skipped-record behavior are fixture tested.
All Nautilus crates share one revision, feature set, precision policy, and license review.
Raw DBN and broad internal Data enums do not become QuestDB or browser contracts.

EvidenceOfficial Databento integration docs and crates/adapters/databento source.

Enforce crate directionmise x -- task check:arch

Outward dependencies and missing workspace lint inheritance fail.