Best practices
Status: Stable (guidance)
Namespaces
One concern per namespace. Never put : in namespace or key.
TTL & policies
Prefer named policies for recurring TTLs. Resolution: per-write ttl → policy → instance default → none. Use cleanup() when you need quota back without reading every key.
Migrations
Bump schemaVersion when the value shape changes; ship migrate before readers expect the new version. has / peek do not migrate — call get.
Adapters
| Need | Adapter |
|---|---|
| Tests / ephemeral | createMemoryAdapter() |
| Survive reload | createLocalStorageAdapter() |
| Tab scoped | createSessionStorageAdapter() |
Never auto-select. On SSR, avoid web adapters until the client, or use memory.
Capabilities
Import Experimental subpaths only when needed. transaction is same-tab batching, not multi-tab ACID. observe is in-process only.
When not to use Storage
Reactive app state, Form Intelligence drafts, large queryable datasets, or secrets that must survive XSS.