Definition of Done

A bijux-gnss-core change is not done when code compiles. It is done when the contract change, if any, is legible and defended.

Completion Gate

changed surface	done means	first proof
public exports	api.rs exposes only deliberate shared contracts	cargo test -p bijux-gnss-core --test public_api_guardrail
artifact payloads	validation rejects incoherent payloads and preserves versioned meaning	nav_artifact_validation or tracking_artifact_validation
observation and tracking records	receiver and nav can read the same record meaning without solver or runtime leakage	contract docs plus the changed record tests
time, units, and coordinates	edge cases remain explicit and portable across consumers	cargo test -p bijux-gnss-core --test prop_timekeeping
diagnostics and support matrix	shared diagnostic and capability records remain stable across runtime, infra, and command layers	support/diagnostic docs plus guardrail proof
serialization	old and new readers can still interpret persisted meaning honestly	SERIALIZATION.md plus artifact validation proof

Not Done Yet Means

• a helper was made public before it had shared-contract meaning
• serialized meaning changed but the docs still describe the old behavior
• invariants are implicit in test names only
• the crate absorbed behavior because it was easier than naming a downstream owner

Reader Questions Before Commit

• Which contract family moved?
• Which higher crates read that meaning today?
• Is the change versioned, serialized, or public?
• What fixture or property test would catch a wrong interpretation?
• Did any product behavior move into core because it was convenient?

Proof Route

Read crates/bijux-gnss-core/docs/CONTRACTS.md, CONTRACT_MAP.md, PUBLIC_API.md, SERIALIZATION.md, and TESTS.md as needed for the changed family. A core change is done only when the public promise, contract prose, source behavior, and protecting tests all describe the same shared meaning.