Schema and stable identifiers

Split definition from state

Definition: Primary Asset ID / row ID / tag -> display, class, tuning, soft assets
Save record: stable instance ID -> definition ID + minimal mutable values
Runtime: resolved definition + validated mutable record + transient caches

Use value structs/arrays/maps in the SaveGame object. Avoid world pointers, components, delegates, latent actions, timers, UI objects, replicated caches, and derived presentation data.

Header fields

Include at least:

• format magic/product namespace when using a custom envelope;
• save schema version and optional subsystem versions;
• build/content compatibility identifier;
• slot/profile ID and platform-user binding policy;
• creation/update time for display only, not authority;
• map/checkpoint identity and playtime if needed;
• payload validation/checksum metadata when your format provides it.

Identity

• placed persistent actor: authored stable GUID/domain ID stored with the actor;
• runtime-spawned actor: generated persistent instance ID plus definition ID and spawn record;
• item/quest/ability: stable domain/Primary Asset ID, never display text or array index;
• map: soft world/Primary Asset identity or governed map ID;
• destroyed/consumed placed actor: tombstone/state record keyed by stable actor ID.

Validate uniqueness in editor/CI. Duplication workflows must generate or deliberately preserve IDs based on semantic identity; accidental duplicate GUIDs make load order decide state.