Avalonia is a mature, cross-platform UI framework for .NET, enabling developers to build desktop, mobile, and web applications with a single codebase. It provides a rich set of controls, a powerful styling system, data binding, animations, and platform-specific backends (Windows, Linux, macOS, Android, iOS, Browser). The architecture is modular: core libraries (Avalonia.Base, Avalonia.Controls) define the property system, layout, input, and rendering, while platform backends implement windowing, graphics (Skia, Vulkan, OpenGL), and accessibility. The framework includes a XAML compiler, source generators, and extensive testing infrastructure. It is actively maintained with a large community and is used in production applications.
ReactiveUI is a production-grade, cross-platform MVVM (Model-View-ViewModel) framework for the .NET ecosystem. Its architecture is centered around reactive primitives (ReactiveObject, ReactiveProperty, IObservable) that form the backbone of its view model layer. The framework employs a fluent builder pattern (RxAppBuilder) for application initialization, a custom dependency injection system ('Splat'), and extensive source code generation to provide a type-safe, AOT-compatible binding and view resolution system. It abstracts platform-specific UI toolkits (WPF, WinUI, MAUI, WinForms, AndroidX, iOS/macOS UIKit, Blazor) behind a consistent set of interfaces (IViewFor<T>, IRoutableViewModel, IActivatableViewModel). The codebase demonstrates strong engineering practices, including a sophisticated reactive command pattern (ReactiveCommand), a typed message bus (MessageBus), a state persistence lifecycle (SuspensionHost), and a collection change-set streaming mechanism (ReactiveChangeSet). A significant portion of the code is dedicated to ensuring Ahead-of-Time (AOT) compilation safety, avoiding reflection where possible through generic view resolution and explicit registration, which is a non-trivial and well-executed design constraint. The repository includes extensive unit tests, platform-specific integration tests, and performance benchmarks. While the framework is actively maintained (evidenced by recent commits, low open issue count, and zero Dependabot alerts), its ambitious scope introduces inherent complexity. The reliance on a custom DI framework, conditional compilation flags (REACTIVE_SHIM), and the maintenance burden of supporting eight distinct UI platforms are notable architectural trade-offs. Despite this, the core abstractions are cleanly separated, highly reusable, and represent a high standard of craftsmanship in the .NET reactive programming space.
Refit is a .NET library that automatically generates type-safe HTTP API clients from C# interfaces decorated with attributes like [Get], [Post], [Header], [Body], and [Query]. It operates via two parallel request-building paths: a Roslyn source generator that emits inline request construction at compile time (trim/AOT-safe), and a reflection-based fallback for unsupported shapes. The library integrates deeply with Microsoft.Extensions.DependencyInjection and IHttpClientFactory, providing extension methods like AddRefitClient<T> and AddKeyedRefitClient for managed HTTP client lifecycles. It supports multiple serializers (System.Text.Json, Newtonsoft.Json, XML), content compression (gzip, Brotli, Zstandard), streaming responses (IAsyncEnumerable, JSON Lines, SSE), multipart form data, and per-request timeouts and authorization via DelegatingHandler pipelines. The architecture is modular: the core Refit package provides attributes, serialization interfaces, and the runtime GeneratedRequestRunner; Refit.HttpClientFactory adds DI integration; Refit.Newtonsoft.Json and Refit.Xml provide alternative serializers; Refit.Reflection offers the runtime request builder; and Refit.Testing supplies StubHttp and Reply for unit testing without a live server. The source generator (InterfaceStubGeneratorV2) is an incremental generator that parses interfaces and emits partial classes into the consumer assembly, using value-equatable models (ImmutableEquatableArray) for caching. The reflection path caches parsed method metadata and builds requests via delegates, ensuring parity with generated code. Key entry points include RestService.For<T>() for creating clients, AddRefitClient<T>() for DI registration, and RefitSettings for central configuration. External dependencies are minimal: System.Text.Json (built-in), Microsoft.Extensions.Http, and optionally Newtonsoft.Json or System.Xml. The library is extensively tested with unit tests, integration tests, snapshot-based generator tests, and benchmarks measuring allocation and throughput. It targets .NET 8/9/10/11 and .NET Framework 4.6.2+, with polyfills for missing BCL types.
This repository contains Stratum, a free and open-source two-factor authentication (2FA) app for Android with Wear OS support. It implements TOTP, HOTP, Steam, Yandex, and mOTP code generation algorithms with configurable parameters. The app features encrypted local backups with AES-GCM/CBC and Argon2id/PBKDF2 key derivation, import from over 15 third-party authenticator apps (Aegis, Bitwarden, KeePass, etc.), QR code scanning via CameraX, and a Material Design 3 UI. The architecture follows a clean layered pattern with a core library (Stratum.Core) containing domain entities, OTP generators, backup converters, and service interfaces, a Droid project for the phone UI, and a Wear OS project. The codebase is well-organized with dependency injection (Autofac), repository pattern for SQLite persistence, and unit tests. It demonstrates strong data engineering skills in reverse-engineering and parsing various backup formats, implementing custom cryptography for Ente Auth, and maintaining a large icon database. The project is actively maintained, targets .NET 10, and has localization in 27+ languages.
This is a cross-platform software development kit (SDK) for rendering Adaptive Cards—a JSON-based card format used by Microsoft products like Teams, Outlook, and Cortana. The repository provides a shared C++ object model for parsing and serializing card definitions, along with platform-specific renderers for Android, iOS, UWP (WinUI), .NET (WPF), and Node.js. It also includes a templating engine for dynamic data binding, a visual designer tool, and multiple test applications. The architecture is a library/framework model: each platform has its own rendering layer that converts the parsed card model into native UI components. The codebase is large and well-organized, with clear separation between the shared model and platform implementations. However, feature parity across platforms is incomplete (e.g., v1.5 features are missing in .NET renderer), and there is significant duplication of logic across platforms, which introduces maintenance risk.
The 32feet.NET repository provides a comprehensive Bluetooth and OBEX protocol implementation for .NET, supporting multiple platforms and Bluetooth stacks.