This module provides a small abstraction for storing key/value data that can survive app reinstall and device restore flows. On Play/Internal builds it is backed by Google Play Block Store, and on F-Droid it is backed by a dummy implementation that reports unavailability.

• persistent-storage-api: public contract (PersistentStorage, availability model, and key abstraction)
• persistent-storage-impl: real implementation using Block Store (play and internal flavors)
• persistent-storage-dummy-impl: fallback implementation for fdroid flavor

• Consumers inject PersistentStorage from persistent-storage-api
• Keys are module-owned subclasses of PersistentStorageKey with a globally unique key string
• checkAvailability() should be called before read/write operations when a feature depends on persistence being available
• store, retrieve, and clear return Result and fail with PersistentStorageUnavailableException when unsupported
• shouldBackupToCloud controls whether stored values are eligible for cloud backup

object MyFeatureKeys {
    object SessionSeed : PersistentStorageKey(
        key = "com.duckduckgo.myfeature.session.seed",
        shouldBackupToCloud = false,
    )
}

class MyFeatureRepository @Inject constructor(
    private val persistentStorage: PersistentStorage,
) {
    suspend fun save(seed: ByteArray): Result<Unit> {
        return persistentStorage.store(MyFeatureKeys.SessionSeed, seed)
    }
}

## Who can help you better understand this feature?

• Craig Russell

• Internal Knowledge Sharing
• Official docs