Open-source alternatives to Rust Crdt

Loro is a conflict-free replicated data type (CRDT) framework and collaborative state engine designed for building real-time collaborative applications. It provides a distributed data synchronizer that enables multiple users to edit shared documents and complex nested structures—such as maps, lists, trees, and counters—with automatic state convergence without requiring a central server. The project distinguishes itself through a versioned document store that supports branching, forking, and merging via a directed acyclic graph of causal operation history. It enables advanced version control c

ShareJS is a collaborative document database and synchronization engine designed for real-time shared state management. It provides an operational transform sync engine to enable simultaneous editing of plain-text and JSON data, and a RESTful synchronization API for managing document states via HTTP. The system features an offline-first data sync layer that queues local modifications while disconnected and automatically pushes edits upon reconnection. It also includes a middleware access control layer that intercepts database requests to enforce security policies and perform request rewriting

Dragonboat is a Go implementation of the Raft consensus protocol designed to maintain consistent state across a distributed cluster of nodes. It provides a library for building distributed state machines that ensure data integrity and fault tolerance during system failures. The project distinguishes itself through a multi-group Raft implementation, which partitions data across independent consensus groups to distribute workloads and increase overall system processing capacity. It also incorporates mutual TLS to encrypt inter-node communication and verify the identity of cluster members. The

This project is a reactive, offline-first NoSQL database engine designed for JavaScript applications. It provides a robust framework for managing application state by synchronizing data across browsers, mobile devices, and server-side runtimes. By treating local storage as the primary source of truth, it enables applications to remain functional without network connectivity, automatically reconciling changes with remote backends once a connection is restored. The database distinguishes itself through a modular architecture that supports cross-environment synchronization and high-performance d

This project provides educational materials and courseware focused on the theoretical and practical foundations of distributed systems design. It serves as a comprehensive curriculum covering the disciplines of consensus, data consistency, reliability engineering, and scalability. The instructional content focuses on achieving cluster agreement through consensus algorithms and managing system-wide state via coordination frameworks. It includes a dedicated guide to data theory, exploring replication strategies, consistency models, and data convergence. The courseware covers a broad capability

PowerDNS is DNS server software used for serving authoritative and recursive DNS records. It functions as both an authoritative DNS server, providing definitive records for specific domains from trusted databases, and a recursive DNS resolver that finds answers for any domain by iteratively querying external servers. The project distinguishes itself through a backend-abstraction layer that decouples server logic from data storage, allowing records to be served from SQL databases, zone files, and external APIs. It includes a geo-aware DNS router to direct users to the nearest server based on t

Yjs is a CRDT framework and real-time state synchronization engine providing shared data types for collaborative software. It functions as a shared data type library of collaborative maps, arrays, and text structures that converge automatically across distributed clients, serving as a local-first data store and a collaborative editor backend. The system distinguishes itself through a synchronization engine that encodes document changes into commutative binary updates. It employs state-vector based differencing to transmit only missing incremental updates between peers and uses relative-positi

Gun is a decentralized graph database and synchronization engine designed for real-time, peer-to-peer data management. It functions as a JavaScript library that enables applications to maintain consistent state across distributed nodes without relying on a central server. By utilizing conflict-free replicated data types and a gossip protocol, the system ensures that data updates propagate across the network and reconcile automatically. The project distinguishes itself through a focus on decentralized identity and security, utilizing public-key infrastructure to authenticate users and sign dat

BlockNote is a block-based rich text editor and a real-time collaborative workspace. It uses a JSON-based data model to organize content into draggable, nestable blocks rather than a single flat document. The system functions as a high-level interface built on ProseMirror that abstracts document state into discrete, manipulatable content blocks. The project serves as a framework for integrating large language models into document editors, enabling context-aware text generation and AI-driven workflows. It also acts as a document export engine capable of converting structured block data into fo

OrbitDB is a decentralized data storage system that enables the creation of serverless databases residing across a network of peers. It functions as a peer-to-peer database that integrates with a content-addressed storage layer to distribute and replicate data without a central server. The system utilizes conflict-free replicated data types to ensure eventual consistency and state convergence across distributed nodes. It maintains an immutable record of updates using a directed acyclic graph to preserve causal ordering and cryptographic integrity. Access is managed through a decentralized ide

Electric is a Postgres data synchronization engine and replication proxy designed to enable local-first software. It replicates data from Postgres databases to client-side stores in real time using logical replication, allowing applications to maintain a local embedded database for offline access and low-latency updates. The system distinguishes itself by using shapes to filter and authorize specific subsets of database rows and columns before streaming them to clients or edge workers. It further supports multi-user collaboration by integrating a conflict-free replicated data type framework t

Orbit DB is a decentralized NoSQL database that utilizes conflict-free replicated data types to ensure eventual consistency across a network of nodes. It functions as a peer-to-peer data store that uses IPFS for content-addressing and synchronization, allowing for the maintenance of application state without a central server or authority. The system is built upon a cryptographically verifiable, immutable operation log, which serves as the foundation for custom decentralized data models. This architecture enables the implementation of various data storage patterns, including JSON document stor

BlockSuite is a collaborative block editor framework built on a hierarchical block tree data model with CRDT-based state synchronization for real-time multi-user editing. It provides an extensible block component system, allowing developers to define custom block types through declarative schemas, services, and rendering components. The editor is packaged as cross-framework web components, making it embeddable in any JavaScript environment. The framework distinguishes itself with a command-driven editing pipeline that composes type-safe editing actions with dynamic context sharing and control

AFFiNE is a collaborative knowledge base and productivity suite designed as a private-first, local-first platform. It provides an integrated workspace that combines structured documents with an infinite digital canvas, allowing users to organize complex information through a block-based model. By prioritizing local data persistence, the platform ensures immediate responsiveness and data sovereignty while maintaining a distributed state for real-time synchronization across multiple devices. The platform distinguishes itself through a canvas-integrated database engine that enables transitions b

This project is a self-hosted documentation platform designed for collaborative knowledge base management. It provides a block-based editor that structures content as a tree of independent nodes, allowing for flexible layout composition and the creation of complex, nested document hierarchies. The platform distinguishes itself through an offline-first architecture that utilizes conflict-free replicated data types to maintain synchronization across multiple clients. This ensures that teams can continue editing content during network disconnections, with all changes merging automatically once c

This project is a distributed headless Chrome web crawler and data extraction framework. It functions as a JavaScript rendering engine that uses a headless browser to process dynamic pages, extracting structured data from websites that require JavaScript execution. The system is designed for scalable data collection across multiple nodes, using distributed task synchronization and shared caches to prevent duplicate work. It distinguishes itself through the ability to emulate specific client environments by configuring user agents and viewport dimensions, while capturing visual evidence such a

This project is a feature flag library for Elixir applications, designed to manage and toggle application functionality at runtime. It provides a distributed system for controlling code paths without requiring new deployments, allowing developers to enable or disable features globally, for specific users, or for defined groups. The library distinguishes itself through a pluggable persistence framework that supports various storage backends, ensuring that flag configurations remain consistent across application restarts. It maintains state synchronization across distributed nodes using messagi

Hoodie is a data synchronization framework and offline-first JavaScript backend designed to keep client-side data stores in sync with a remote backend. It provides a local-first persistence layer that allows applications to remain functional while offline by abstracting the client-side database. The system features a NoSQL backend interface that enables interaction with remote data stores without requiring custom server-side boilerplate code. This is supported by a modular driver system of pluggable backend adapters that connect the synchronization layer to various remote database providers.

SyncTrayzor is a native Windows tray wrapper and management interface for Syncthing. It functions as a process manager that ensures the synchronization service starts automatically upon user login and remains active in the background. The project provides a built-in browser to render the Syncthing web interface and includes a specialized conflict resolver tool to identify and fix versioning mismatches between synchronized files. It integrates directly into the system tray to provide service status updates and desktop notifications. Capability areas include synchronization monitoring for trac

Remotely Save is a cloud storage synchronization tool and backup manager designed to keep local files and application data consistent across desktop and mobile devices. It functions as a cross-platform synchronizer that mirrors local data to remote servers using S3 and other cloud protocols. The project focuses on privacy and security through end-to-end encryption, which secures files with a user-defined password before they are uploaded to remote cloud services. It ensures data remains private on third-party servers by applying symmetric client-side encryption. The system includes capabilit

ShedLock is a distributed lock manager designed to prevent scheduled tasks from running concurrently across multiple nodes in a distributed system. It acts as a task coordinator that ensures a single execution of timed jobs by managing lock lifespans and utilizing external lock providers. The system utilizes database-backed providers to store task execution states in external databases, synchronizing locks across active cluster nodes. It includes a clock-drift tolerant synchronizer that handles time discrepancies between distributed nodes through the use of shared timestamps and flexible lock

Derby is an isomorphic MVC framework and real-time data synchronization engine designed for building collaborative applications. It functions as a bi-directional data binding library and template engine that shares a single codebase between Node.js and the browser to synchronize state across clients and servers. The framework distinguishes itself through the use of operational transformation to resolve data conflicts automatically, enabling real-time shared editing and multi-user collaboration. It employs a differential state mutation model to minimize updates by performing deep equality chec

netty-socketio is a Java implementation of a Socket.IO server designed for real-time bidirectional communication between clients and servers. It functions as a real-time event engine and WebSocket communication server, utilizing the Netty network framework to manage high-performance socket connections. The project enables distributed socket server scaling by acting as a distributed message broker. It synchronizes client states and broadcasts messages across multiple server nodes through the use of an external data store. The system manages traffic via namespace-based connection routing and r

Raft-java is a lightweight Java consensus library and replicated state machine engine designed to synchronize transaction logs and maintain fault-tolerant state across distributed server nodes. The framework relies on a leader-based replication model that routes write operations through a designated coordinator node, executing RPC-driven consensus protocols and automatic leader elections to maintain cluster agreement. The library supports dynamic cluster membership changes, allowing nodes to be added or removed during runtime without downtime through joint consensus configuration entries app

sofa-jraft is a Java implementation of the Raft consensus algorithm. It serves as a distributed consensus engine and linearizable state machine designed to ensure high availability and data consistency across a cluster of nodes. The project provides a replicated key-value store and a coordination engine for managing distributed state. It distinguishes itself through support for multi-group consensus sharding to distribute traffic and a service provider interface that allows for custom log storage and entry encoding implementations. The system covers a wide range of distributed capabilities,

Zed is an AI-native, high-performance code editor designed for extreme responsiveness and keyboard-centric workflows. It functions as an extensible text processing workspace that integrates autonomous agents and predictive models directly into the development environment to automate complex engineering tasks, refactoring, and code generation. The editor distinguishes itself through a GPU-accelerated rendering pipeline and an asynchronous multi-threaded architecture that ensures low-latency interaction even with large-scale projects. It features built-in support for real-time, multi-user colla

mcp-context-forge is a Model Context Protocol federation gateway that unifies diverse AI tool servers and APIs into a single consistent interface for discovery and execution. It acts as a centralized proxy that aggregates multiple servers and APIs, allowing AI agents to access and invoke a unified set of tools, prompts, and resources. The project distinguishes itself through a multi-protocol translation bridge that converts communication between standard I/O, SSE, gRPC, and REST to enable interoperability between disparate tool servers. It includes a comprehensive LLM evaluation framework for