[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › local‑first/Storage Encrypted storage layer for local-first data. ## Core Types | Interface | Description | | ------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- | | [ValidDbChangeValuesError](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/ValidDbChangeValuesError) | A plain structured error produced by a [Type](https://evolu.dev/docs/api-reference/common/Type/interfaces/Type) operation. | ## Functions | Function | Description | | --------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [createBaseSqliteStorage](https://evolu.dev/docs/api-reference/common/local-first/Storage/functions/createBaseSqliteStorage) | Creates a [BaseSqliteStorage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/BaseSqliteStorage) implementation. | | [createBaseSqliteStorageTables](https://evolu.dev/docs/api-reference/common/local-first/Storage/functions/createBaseSqliteStorageTables) | - | | [getTimestampByIndex](https://evolu.dev/docs/api-reference/common/local-first/Storage/functions/getTimestampByIndex) | - | | [getTimestampInsertStrategy](https://evolu.dev/docs/api-reference/common/local-first/Storage/functions/getTimestampInsertStrategy) | Determines the insertion strategy for a timestamp based on its position relative to the current first and last timestamps. | | [readOwnerUsageOrDefault](https://evolu.dev/docs/api-reference/common/local-first/Storage/functions/readOwnerUsageOrDefault) | Reads owner usage from SQLite and returns default bounds when absent. | | [testCreateCrdtMessage](https://evolu.dev/docs/api-reference/common/local-first/Storage/functions/testCreateCrdtMessage) | Test helper for creating a simple [CrdtMessage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/CrdtMessage). | | [testFingerprintTimestamps](https://evolu.dev/docs/api-reference/common/local-first/Storage/functions/testFingerprintTimestamps) | Computes a brute-force [Fingerprint](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/Fingerprint) from [TimestampBytes](https://evolu.dev/docs/api-reference/common/local-first/Timestamp/variables/TimestampBytes) values for tests and benchmarks. | | [timestampBytesToFingerprint](https://evolu.dev/docs/api-reference/common/local-first/Storage/functions/timestampBytesToFingerprint) | - | | [updateOwnerUsage](https://evolu.dev/docs/api-reference/common/local-first/Storage/functions/updateOwnerUsage) | Updates timestamp bounds in evolu_usage table. | ## Interfaces | Interface | Description | | ---------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [BaseRange](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/BaseRange) | - | | [BaseSqliteStorage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/BaseSqliteStorage) | Common interface for both client and relay SQLite storages. | | [BaseSqliteStorageDep](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/BaseSqliteStorageDep) | - | | [CrdtMessage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/CrdtMessage) | A CRDT message combining a unique [Timestamp](https://evolu.dev/docs/api-reference/common/local-first/Timestamp/variables/Timestamp) with a [DbChange](https://evolu.dev/docs/api-reference/common/local-first/Storage/variables/DbChange). | | [DbChange](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/DbChange) | A DbChange is a change to a table row. Together with a unique [Timestamp](https://evolu.dev/docs/api-reference/common/local-first/Timestamp/variables/Timestamp), it forms a [CrdtMessage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/CrdtMessage). | | [EncryptedCrdtMessage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/EncryptedCrdtMessage) | An encrypted [CrdtMessage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/CrdtMessage). | | [FingerprintRange](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/FingerprintRange) | - | | [SkipRange](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/SkipRange) | - | | [Storage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/Storage) | Evolu Storage. | | [StorageConfig](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/StorageConfig) | - | | [StorageDep](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/StorageDep) | - | | [StorageQuotaError](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/StorageQuotaError) | Error when storage or billing quota is exceeded. | | [TimestampsRange](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/TimestampsRange) | - | ## Type Aliases | Type Alias | Description | | -------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [DbChangeValues](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/DbChangeValues) | - | | [EncryptedDbChange](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/EncryptedDbChange) | Encrypted DbChange | | [Fingerprint](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/Fingerprint) | A cryptographic hash used for efficiently comparing collections of [TimestampBytes](https://evolu.dev/docs/api-reference/common/local-first/Timestamp/variables/TimestampBytes)es. | | [InfiniteUpperBound](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/InfiniteUpperBound) | - | | [Range](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/Range) | - | | [RangeType](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/RangeType) | - | | [RangeUpperBound](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/RangeUpperBound) | Union type for Range's upperBound: either a [TimestampBytes](https://evolu.dev/docs/api-reference/common/local-first/Timestamp/variables/TimestampBytes) or [InfiniteUpperBound](https://evolu.dev/docs/api-reference/common/local-first/Storage/variables/InfiniteUpperBound). | | [SqliteStorageDeps](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/SqliteStorageDeps) | - | | [StorageInsertTimestampStrategy](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/StorageInsertTimestampStrategy) | - | | [ValidDbChangeValues](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/ValidDbChangeValues) | - | ## Variables | Variable | Description | | ------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [DbChange](https://evolu.dev/docs/api-reference/common/local-first/Storage/variables/DbChange) | A DbChange is a change to a table row. Together with a unique [Timestamp](https://evolu.dev/docs/api-reference/common/local-first/Timestamp/variables/Timestamp), it forms a [CrdtMessage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/CrdtMessage). | | [DbChangeValues](https://evolu.dev/docs/api-reference/common/local-first/Storage/variables/DbChangeValues) | - | | [fingerprintSize](https://evolu.dev/docs/api-reference/common/local-first/Storage/variables/fingerprintSize) | - | | [InfiniteUpperBound](https://evolu.dev/docs/api-reference/common/local-first/Storage/variables/InfiniteUpperBound) | - | | [RangeType](https://evolu.dev/docs/api-reference/common/local-first/Storage/variables/RangeType) | - | | [ValidDbChangeValues](https://evolu.dev/docs/api-reference/common/local-first/Storage/variables/ValidDbChangeValues) | - | | [zeroFingerprint](https://evolu.dev/docs/api-reference/common/local-first/Storage/variables/zeroFingerprint) | A fingerprint of an empty range. |