Akavache: An Asynchronous Key-Value Store for Native Applications

Akavache is an asynchronous, persistent (i.e., writes to disk) key-value store created for writing desktop and mobile applications in C#, based on SQLite3. Akavache is great for both storing important data (i.e., user settings) as well as cached local data that expires.

What's New in V12

Akavache V12 rewrites the SQLite backend for direct SQLitePCLRaw 3.x access, replacing the sqlite-net-pcl ORM layer entirely. The result is lower per-operation allocations, dedicated worker-thread serialization of all native handle access, and commit coalescing for concurrent writes.

• SQLitePCLRaw direct access: Prepared statements cached and reused, parameters bound positionally — no ORM overhead
• SQLite3MultipleCiphers: Encrypted databases use SQLite3MC instead of sqlcipher
• Observable-first settings: SettingsBase properties are IObservable<T> — no more .Wait() deadlocks
• AOT-safe serialization: JsonTypeInfo<T> overloads for System.Text.Json, trim-safe out of the box
• System.Text.Json package split: Pure JSON package no longer pulls in Newtonsoft.Json
• Thread-safe disposal: All cache types use lock-free Interlocked patterns for idempotent dispose

See the Migration Guide: V11 to V12 for upgrade instructions.

Quick Start

1. Install Packages

<PackageReference Include="Akavache.Sqlite3" Version="*" />
<PackageReference Include="Akavache.SystemTextJson" Version="*" />

2. Initialize Akavache

Note: WithAkavache, WithAkavacheCacheDatabase and Initialize always requires an ISerializer defined as a generic type, such as WithAkavache<SystemJsonSerializer>. This ensures the cache instance is properly configured for serialization.

Static Initialization (Recommended for most apps)

using Akavache.Core;
using Akavache.SystemTextJson;
using Akavache.Sqlite3;
using Splat.Builder;

// Initialize with the builder pattern
AppBuilder.CreateSplatBuilder()
    .WithAkavacheCacheDatabase<SystemJsonSerializer>(builder =>
        builder.WithSqliteProvider() // REQUIRED: Explicitly initialize SQLite provider
               .WithSqliteDefaults(),
            "MyApp");

Important: Always call WithSqliteProvider() explicitly before WithSqliteDefaults(). While WithSqliteDefaults() will automatically call WithSqliteProvider() if not already initialized (for backward compatibility), this automatic behavior is deprecated and may be removed in future versions. Explicit provider initialization is the recommended pattern for forward compatibility with other DI containers.

Dependency Injection Registration (for DI containers)

using Akavache.Core;
using Akavache.SystemTextJson;
using Akavache.Sqlite3;
using Splat.Builder;

// Example: Register Akavache with Splat DI
AppBuilder.CreateSplatBuilder()
    .WithAkavache<SystemJsonSerializer>(
        "MyApp",
        builder => builder.WithSqliteProvider()    // REQUIRED: Explicit provider initialization
                          .WithSqliteDefaults(),
        (splat, instance) => splat.RegisterLazySingleton(() => instance));

// For in-memory cache (testing or lightweight scenarios):
AppBuilder.CreateSplatBuilder()
    .WithAkavache<SystemJsonSerializer>(
        "Akavache",
        builder => builder.WithInMemoryDefaults(),  // No provider needed for in-memory
        (splat, instance) => splat.RegisterLazySingleton(() => instance));

3. Use the Cache

Basic Operations

// Store an object
var user = new User { Name = "John", Email = "[email protected]" };
await CacheDatabase.UserAccount.InsertObject("current_user", user);

// Retrieve an object
var cachedUser = await CacheDatabase.UserAccount.GetObject<User>("current_user");

// Store with expiration
await CacheDatabase.LocalMachine.InsertObject("temp_data", someData, DateTimeOffset.Now.AddHours(1));

// Get or fetch pattern
var data = await CacheDatabase.LocalMachine.GetOrFetchObject("api_data", 
    async () => await httpClient.GetFromJsonAsync<ApiResponse>("https://api.example.com/data"));

Cache Types

Akavache provides four types of caches:

• UserAccount: User settings and preferences that should persist and potentially sync
• LocalMachine: Cached data that can be safely deleted by the system
• Secure: Encrypted storage for sensitive data like credentials and API keys
• InMemory: Temporary storage that doesn't persist between app sessions

// User preferences (persistent)
await CacheDatabase.UserAccount.InsertObject("user_settings", settings);

// API cache (temporary)
await CacheDatabase.LocalMachine.InsertObject("api_cache", apiData, DateTimeOffset.Now.AddHours(6));

// Sensitive data (encrypted)
await CacheDatabase.Secure.SaveLogin("john.doe", "secretPassword", "myapp.com");

// Session data (in-memory only)
await CacheDatabase.InMemory.InsertObject("current_session", sessionData);

NuGet Packages

Install the packages that match your needs. At minimum you need the core package plus a storage backend and a serializer.

Purpose	Package	NuGet
Core (in-memory cache)	Akavache
SQLite persistence	Akavache.Sqlite3
Encrypted SQLite persistence	Akavache.EncryptedSqlite3
System.Text.Json serializer (recommended)	Akavache.SystemTextJson
System.Text.Json BSON serializer	Akavache.SystemTextJson.Bson
Newtonsoft.Json serializer	Akavache.NewtonsoftJson
HTTP download and caching extensions	Akavache.HttpDownloader
Image/bitmap caching	Akavache.Drawing
Application settings helpers	Akavache.Settings
V10 → V11 data migration	Akavache.V10toV11

Installation

Akavache uses a modular package structure. Choose the packages that match your needs:

Core Package (In Memory only)

<PackageReference Include="Akavache" Version="*" />

Storage Backends (Choose One - Recommended)

<!-- SQLite persistence (most common) -->
<PackageReference Include="Akavache.Sqlite3" Version="*" />

<!-- Encrypted SQLite persistence -->
<PackageReference Include="Akavache.EncryptedSqlite3" Version="*" />

Serializers (Choose One - Required)

<!-- System.Text.Json (fastest, .NET native) -->
<PackageReference Include="Akavache.SystemTextJson" Version="*" />

<!-- Newtonsoft.Json (most compatible) -->
<PackageReference Include="Akavache.NewtonsoftJson" Version="*" />

Optional Extensions

<!-- HTTP download and caching extensions -->
<PackageReference Include="Akavache.HttpDownloader" Version="*" />

<!-- Image/Bitmap support -->
<PackageReference Include="Akavache.Drawing" Version="*" />

<!-- Settings helpers -->
<PackageReference Include="Akavache.Settings" Version="*" />

Framework Support

Akavache supports:

• ✅ .NET Framework 4.6.2/4.7.2 - Windows desktop applications
• ✅ .NET Standard 2.0 - Cross-platform libraries
• ✅ .NET 8.0 - Modern .NET applications
• ✅ .NET 9.0 - Latest .NET applications
• ✅ .NET 10.0 - Latest .NET applications
• ✅ Mobile Targets - net9.0-android, net9.0-ios, net9.0-maccatalyst, net10.0-android, net10.0-ios, net10.0-maccatalyst
• ✅ Desktop Targets - net9.0-windows10.0.19041.0, net10.0-windows10.0.19041.0 (WinUI), net9.0, net10.0 (cross-platform)

Serializer Compatibility

Serializer	.NET Framework 4.6.2+	.NET 8.0+	Mobile	Performance
System.Text.Json	✅ Via NuGet	✅	✅	Fastest
Newtonsoft.Json	✅ Built-in	✅	✅	Compatible

Recommendation: Use System.Text.Json for new projects for best performance. Use Newtonsoft.Json when migrating from older Akavache versions or when you need maximum compatibility.

Akavache.Settings: Configuration Made Easy

Akavache.Settings provides a specialized settings database for application configuration that survives app updates and reinstalls.

Quick Settings Example

using Akavache.Settings;

// 1. Create a settings class — properties are IObservable<T>
public class AppSettings : SettingsBase
{
    public AppSettings() : base(nameof(AppSettings)) { }

    public IObservable<bool> EnableNotifications => GetOrCreateObservable(true);
    public IObservable<Unit> SetEnableNotifications(bool value) => SetObservable(value, nameof(EnableNotifications));

    public IObservable<string> UserName => GetOrCreateObservable("DefaultUser");
    public IObservable<Unit> SetUserName(string value) => SetObservable(value, nameof(UserName));
}

// 2. Initialize with your app
var appSettings = default(AppSettings);

AppBuilder.CreateSplatBuilder()
    .WithAkavache<SystemJsonSerializer>(builder =>
        builder.WithApplicationName("MyApp")
               .WithSqliteProvider()
               .WithSettingsStore<AppSettings>(settings => appSettings = settings));

// 3. Use the settings — subscribe for live updates or read once
await appSettings.SetUserName("John Doe");
await appSettings.SetEnableNotifications(false);

var name = await appSettings.UserName.FirstAsync();
Console.WriteLine($"User: {name}");

Settings are automatically persisted and will survive app updates, making them perfect for user preferences and application configuration.

Documentation

📚 Complete documentation is available in the /docs folder:

• Installation Guide - Detailed installation and package selection
• Configuration - Builder pattern, providers, and advanced setup
• Serializers - System.Text.Json vs Newtonsoft.Json comparison
• Cache Types - UserAccount, LocalMachine, Secure, and InMemory caches
• Basic Operations - CRUD operations and error handling
• Migration: V10 → V11 - Upgrading from V10.x to V11.x
• Migration: V11 → V12 - Upgrading from V11.x to V12.x
• Settings Management - Complete Akavache.Settings guide
• Platform Notes - Platform-specific guidance
• Performance - Benchmarks and optimization tips
• Best Practices - Recommended patterns and anti-patterns
• Troubleshooting - Common issues and solutions

Support and Contributing

• 📖 Documentation: https://github.com/reactiveui/Akavache
• 🐛 Issues: GitHub Issues
• 💬 Chat: ReactiveUI Slack
• 📦 NuGet: Akavache Packages

Sponsors

JetBrains gives ReactiveUI's maintainers licences for its tools through its open source support programme. Anthropic supports them with Claude through Claude for Open Source. OpenAI supports them with Codex through Codex for Open Source.

This project is tested with BrowserStack.

See our sponsors for more information. JetBrains, Claude, Anthropic, OpenAI and Codex names and logos are trademarks of their respective owners.

License

Akavache is licensed under the MIT License.