Open-source alternatives to Rx.NET

RxKotlin is a reactive programming library and asynchronous stream processor that provides Kotlin language extensions for composing event-based data streams. It serves as a set of Kotlin bindings for RxJava, allowing developers to transform, filter, and flatten sequences of data emitted over time. The library focuses on integrating RxJava patterns into Kotlin projects by applying language-specific conventions and idioms. It utilizes extension functions to simplify reactive programming patterns, reduce boilerplate, and optimize workflows within the reactive ecosystem. The toolkit covers a bro

RxGo is a functional reactive programming library and an implementation of ReactiveX for the Go language. It serves as an asynchronous stream processing toolkit designed to coordinate event-based programs and data flows using the observable pattern. The library enables the construction of asynchronous processing pipelines that transform, filter, and combine event sequences. It distinguishes itself through the use of functional operators to compose these pipelines and provides mechanisms for managing concurrent execution. The toolkit covers a broad range of stream orchestration capabilities,

UniRx is a reactive programming library and event orchestration framework for the Unity engine. It implements observable sequences and functional operators to transform callbacks, coroutines, and engine events into cancellable data streams for unified asynchronous event handling. The library provides a reactive UI binding system that synchronizes data models with user interface elements to trigger automatic visual updates. It includes a type-based publication and subscription system to route messages between producers and consumers, decoupling internal game components. The framework covers a

Faust is a Python library for building distributed stream processing applications that integrate with Kafka. It functions as an asynchronous stream processor designed to handle high-throughput event streams and real-time data analysis using asynchronous functions. The system operates as a distributed stream processor and state store, utilizing sharding and partitioned topics to scale processing workloads horizontally across multiple worker nodes. It maintains state through a replicated key-value storage system backed by local databases to ensure high availability and fast recovery. The frame

RisingWave is a cloud-native streaming database and real-time analytics engine that uses standard SQL to process continuous data streams. It functions as a streaming data lakehouse, combining the capabilities of a streaming SQL database with a platform that integrates streaming ingestion with open table formats. The system is distinguished by its use of the PostgreSQL wire protocol, allowing it to integrate with existing SQL tools and drivers. It employs a decoupled compute and storage architecture, persisting streaming state and materialized views in cloud object storage to enable independen

Hazelcast is a distributed data platform that combines an in-memory data grid with a stream processing engine to support real-time analytics and event-driven applications. It functions as a partitioned, distributed key-value store that replicates data across cluster nodes to provide low-latency access and high availability. The platform also serves as a distributed SQL query engine, allowing users to execute standard SQL statements against both in-memory datasets and external data sources. What distinguishes Hazelcast is its use of a distributed consensus subsystem to maintain strongly consis

RxPY is a functional reactive programming library and a ReactiveX observable library for Python. It serves as an asynchronous stream processor and event-driven coordination framework used to build data pipelines that react to changes in state or streams of events over time. The library provides a toolkit for composing asynchronous and event-based programs using observable sequences and operators. It distinguishes itself through the use of configurable schedulers to manage concurrency, timing, and subscription lifecycles. The project covers a wide range of stream processing capabilities, incl

KotlinMvp is a short-video Android application developed with Kotlin. It utilizes the Model-View-Presenter architectural pattern to maintain a clear separation between business logic and the user interface. The project integrates a short-video playback interface that supports content discovery through category filtering and popularity rankings. It employs a Retrofit REST client for network communication and the RxJava reactive framework to manage asynchronous data streams and background tasks. Image loading and caching are handled via the Glide image loader. The application includes capabili

The Reactive Extensions for JavaScript

ZIO is a functional effect system for the JVM that models asynchronous and concurrent programs as pure, composable values with typed error handling and dependency injection. Its core identity is built on fiber-based concurrency, where lightweight, non-blocking fibers execute millions of concurrent tasks with structured lifecycle management, and a dual-channel error model that separates expected business failures from unexpected system defects at compile time. The system provides effect-typed dependency injection through a layer-based dependency graph, pull-based reactive stream processing with

Bacon.js is a JavaScript functional reactive programming library used for coordinating complex asynchronous data flows. It functions as an observable event stream framework and an asynchronous data flow orchestrator, allowing developers to model events as declarative streams and properties. The library distinguishes itself through its ability to manage reactive state and synchronize timing across multiple sources. It provides specialized mechanisms for atomic state synchronization to prevent glitches in derived properties and offers advanced coordination strategies such as asynchronous stream

Effector is a reactive state management library and data flow orchestrator designed for building complex, event-driven applications. It models application logic as a directed acyclic graph, where state updates and asynchronous side effects propagate automatically through declarative pipelines. By decoupling business logic from user interface layers, it allows developers to maintain state in independent containers that communicate via standard interfaces, ensuring the system remains framework-agnostic. The library distinguishes itself through its robust support for isolated execution scopes, w

ReactiveUI is a .NET MVVM framework and functional reactive programming library designed to decouple application state from the user interface. It functions as a reactive state management tool that uses observable streams to handle mutable data and asynchronous event-driven logic. The framework provides a cross-platform UI toolkit that abstracts business logic from platform-specific views. This enables the creation of consistent user interfaces across multiple .NET platforms by utilizing platform-agnostic abstractions. The system focuses on application state management and decoupled UI testi

Reactor Core is a reactive programming toolkit and non-blocking foundation for composing asynchronous data pipelines on the JVM. It serves as an asynchronous stream processing framework and a backpressure management system, allowing developers to transform, filter, and combine sequences of events while regulating data flow between producers and consumers to prevent resource exhaustion. The library differentiates itself through a sophisticated concurrency scheduling system and demand-based flow control. It decouples signal processing from specific threads using a scheduler registry and provide

RxSwift is a reactive programming library for Swift that provides a framework for managing push-based data flows and composing asynchronous, event-based programs. It utilizes observable sequences and functional operators to transform and filter asynchronous sequences through a declarative approach. The library is distinguished by its ability to link asynchronous data streams directly to user interface elements, automating view updates via reactive data binding. It includes specialized tools for tracking UI control properties and events on the main thread, as well as the ability to encapsulate

language-ext is a functional programming framework for C# that provides a suite of immutable data structures and monadic types. It enables the implementation of pure functional programming patterns, utilizing containers to manage side effects, optional values, and error handling. The library is distinguished by its advanced concurrency and state management tools, including a software transactional memory system and lock-free atomic references. It also provides specialized utilities for distributed systems, such as vector clocks for causality tracking and deterministic data conflict resolution

Backtrader is a Python framework designed for the development, backtesting, and live execution of algorithmic trading strategies. It provides a comprehensive environment for quantitative finance, allowing users to simulate trading logic against historical market data or connect directly to brokerage platforms for automated real-time trading. The project distinguishes itself through a unified event-driven architecture that treats backtesting and live trading with the same API. This consistency is supported by a flexible data-feed abstraction layer that normalizes diverse financial sources, ena

MoreLINQ is a functional programming toolkit and extension library for .NET that augments LINQ to Objects with advanced operators for sequence manipulation and analysis. It provides a set of tools for declarative data transformation, leveraging lazy evaluation and composition to handle complex object sequences. The library is distinguished by its specialized capabilities for combinatorial generation, including the production of permutations, subsets, and Cartesian products. It also provides advanced sequence joining options, such as full, left, and right outer joins, and supports complex data

Cycle.js is a functional reactive web framework and observable-driven UI library used for building web applications. It employs a reactive stream architecture that treats the document object model and side effects as continuous data streams, coordinating state and logic through a functional cycle. The framework distinguishes itself by isolating side effects from core logic using a system of drivers. This architecture maps external events to internal commands through a symmetric input-output pipeline, ensuring that the application remains a cycle of pure functions. The project provides capabi

Azul is a native desktop application builder and UI toolkit for creating high-performance graphical user interfaces. It utilizes a functional and reactive programming model for managing layout and state, enabling the development of native software through a CSS-based toolkit. The framework is distinguished by its use of the WebRender engine to provide GPU-accelerated rendering. This allows the system to display complex user interface elements with high efficiency and speed by leveraging hardware acceleration. The project enables the design of desktop interfaces using a document object model

This project is a comprehensive learning resource and technical reference for reactive programming with RxJS. It provides a structured curriculum, curated examples, and an indexed operator catalog to help developers shift from imperative to declarative programming using observable data streams and functional operators. The repository features a library of reactive UI patterns and implementation recipes. These cover practical applications such as type-ahead search, game loops, gesture-based interactions like swipe-to-refresh, and security overlays like lockscreens. The resource covers a broad

Storm is a distributed stream processing framework designed to execute unbounded computations across a cluster to process real-time data streams. It functions as a data pipeline orchestrator that allows users to define and deploy declarative data flow graphs connecting streaming sources to processing components. The system operates as a multi-tenant distributed compute engine that isolates workloads and limits resource usage across shared clusters using dedicated pools and access control. It is also a secure distributed processing engine that employs encrypted node communication and SSL-secur

Om is a frontend state management library and reactive user interface framework that integrates ClojureScript functional programming with the React virtual DOM rendering engine. It provides a bridge to build responsive web interfaces where visual elements automatically update when underlying application data changes. The project centers on a normalized state store that flattens complex data structures into a relational format. This data is accessed through a reader-based querying system, which decouples the user interface from the state by allowing components to declare specific data requirem

R3 is a reactive extensions library and asynchronous data pipeline framework. It provides a system for composing asynchronous data streams, managing reactive state, and coordinating event sequences using observable patterns. The project distinguishes itself with a deterministic testing toolkit that mocks time and frame updates to ensure reproducible unit tests for asynchronous logic. It also includes observability tools for tracking active subscriptions and generating stack traces to identify memory leaks, alongside centralized exception routing for pipeline recovery. The framework covers a

Fluvio is a distributed event streaming platform and cloud-native streaming engine designed for collecting, persisting, and replicating real-time data streams across a distributed cluster. It functions as a real-time data pipeline for building stateful workflows that ingest, enrich, and export data between external sources and sinks. The platform is distinguished by its use of WebAssembly to execute compiled modules for in-line data transformations and filtering. This allows for the execution of custom business logic to reshape information in motion without requiring a restart of the cluster.

Storm is a distributed stream processing framework and fault-tolerant compute engine designed for executing real-time continuous computations across a cluster of machines. It functions as a stateful stream processor and cluster topology manager, enabling the deployment and monitoring of distributed data flow configurations. The system ensures exactly-once semantics by utilizing transactional state management to guarantee that every message in a data stream is processed exactly one time. It further operates as a distributed RPC system, allowing for the integration of non-native languages throu

Redux is a predictable state container designed to manage global application data through a centralized store. It operates on a unidirectional data flow architecture where state transitions are triggered by dispatching action objects, which are then processed by pure reducer functions to produce a new, immutable state tree. This approach ensures that application data remains consistent and traceable across the entire component hierarchy. The library distinguishes itself through a functional pattern that relies on pure functions for state logic and a middleware-based extension system. This mid