Roblox Data

Roblox data

Read ../../references/roblox-engineering.md. Inspect the existing data layer and every writer before choosing a storage pattern.

Classify the state

• Durable player or game state belongs in DataStoreService.
• Frequent, ephemeral cross-server coordination belongs in MemoryStoreService with explicit expiration and recovery when an entry disappears.
• One-way cross-server notifications may use MessagingService, but the message should identify authoritative state that receivers can reread. Do not make delivery itself the durable record.
• Local caches need an owner, invalidation rule, maximum lifetime, and fallback when the backing service fails.

Preserve correctness

• Keep service access server-side. Define the key format, serializable schema, schema version, defaults, validation, migration, and ownership of each mutation.
• Use atomic update patterns for concurrent or retry-sensitive writes. Keep update callbacks pure and non-yielding; derive the new value only from their arguments and immutable inputs.
• Make rewards, purchases, and other consequential mutations idempotent. Record the operation identifier with the durable outcome so a retry cannot grant twice.
• Use a session lease when multiple servers could write the same player record. Define acquisition, renewal, release, stale-owner recovery, and what gameplay can continue after ownership is lost.
• Wrap service calls, distinguish retryable failure from invalid data, and use bounded backoff with jitter. Never retry in a tight loop or treat failure as an empty profile.
• Treat shutdown saving as a final attempt, not the only persistence path. Bound shutdown work and make player departure, reconnect, teleport, and server failure explicit lifecycle cases.
• Never enable or exercise live DataStore access through an agent-run Studio test. The user performs Studio validation, preferably against a separate test version when durable data is involved.

Deliverable

State the service choice, schema and key format, authority, operation lifecycle, concurrency behavior, failure policy, and migration path. Verify pure serializers, validators, migrations, and idempotency locally; give the user a short Studio checklist for runtime behavior.