Load for server-level or cross-server data: leaderboards (OrderedDataStore), cross-server messaging (MessagingService), temporary queues and sorted maps (MemoryStoreService), shared world state, persistent non-player data, season/guild data. For player data (DataStore, ProfileStore, session locking), use roblox-data; for Open Cloud and external APIs, use roblox-cloud.

Quick Reference

OrderedDataStore (Leaderboards)

Sortable DataStore. Keys are strings; use a stable key such as tostring(UserId).
Values are integers used for sorting; choose the sign and ordering intentionally.
GetSortedAsync(ascending, pageSize, minValue, maxValue) → sorted pages
For leaderboards only, not player data

local D = game:GetService("DataStoreService")
local store = D:GetOrderedDataStore("LeaderboardCoins")
store:SetAsync(tostring(player.UserId), playerCoins)
local top10 = store:GetSortedAsync(false, 10):GetCurrentPage()

MessagingService (Cross-Server)

Real-time server communication: SubscribeAsync / PublishAsync
No delivery or ordering guarantee; design for idempotency.

GlobalDataStore (Shared State)

Persistent non-player state such as guilds, seasons, and counters.
Use UpdateAsync; never use it for player session data.

MemoryStoreService (Temporary Coordination)

Queues and sorted maps for expiring matchmaking, leases, and coordination.
Remove a read batch only after successful, idempotent processing.
Use MessagingService or TeleportData for notification and handoff.

Cross-Server Patterns

Pitfalls

MessagingService is fire-and-forget: no delivery guarantee, no ordering
GlobalDataStore has same rate limits as player DataStores; don't spam
OrderedDataStore keys are strings; values are integers used for sorting
Never store Instances; serialize to primitives first
UpdateAsync for any shared counter to prevent lost updates

Need more detail? Load references/full.md for the complete reference with code examples, API tables, and edge cases.

npx skills add tabooharmony/roblox-brain --skill roblox-server-data