Focused reference · Unreal Engine 5.8

System selector

unreal-save-load/references/system-selector.md

State	Prefer
playthrough/profile/world progress	custom `USaveGame` schema and coordinator
per-local-player data with lifecycle/version helpers	`ULocalPlayerSaveGame`
resolution/window/scalability	`UGameUserSettings`
Enhanced Input key profiles	Enhanced Input User Settings or integrated custom serialization
immutable item/quest/ability definitions	Data Asset/Table/Registry; save stable ID only
map-travel-only runtime state	GameInstance/subsystem/player state, not necessarily disk
server-owned persistent world/account	authoritative backend/database; client save is cache/UI only
interoperable/external data format	explicit custom format plus validation/versioning

Choose one coordinator, commonly a GameInstance Subsystem, to own slot/user policy, snapshot requests, operation serialization, migration registry, callbacks, and telemetry. Individual actors contribute records; they do not independently race writes to the same slot.