Open-source alternatives to Concurrent Map

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

Crawlee-python is a web crawling framework for building scalable scrapers using Python. It serves as a comprehensive tool for web scraping automation, providing a system to extract structured data from websites using both lightweight HTTP requests and headless browser automation. The framework is distinguished by its anti-bot evasion capabilities, which include browser fingerprint impersonation and tiered proxy rotation to bypass detection systems and solve challenges such as Cloudflare. It also incorporates artificial intelligence for autonomous website navigation and schema-based data extra

Carp is a statically typed Lisp compiler that compiles Lisp-like syntax directly to C source code, enabling seamless integration with existing C libraries and low-level system programming. It manages memory deterministically at compile time using ownership tracking and linear types, eliminating garbage collection pauses and runtime overhead while ensuring type safety through an inferred static type system. The language distinguishes itself through compile-time macro expansion and metaprogramming capabilities, allowing code generation and transformation before final binary output. It enforces

Bigcache is a thread-safe, in-memory key-value store for Go designed to minimize garbage collection pauses. It functions as a memory-optimized cache capable of storing gigabytes of data while maintaining low latency during high-volume operations. The system avoids garbage collection overhead by managing memory through large byte arrays and manual allocation. It utilizes a circular-buffer layout to reuse space and lock-striped sharding to reduce contention during concurrent read and write access. The project provides capabilities for high-volume in-memory caching and low-latency data retrieva

Perkeep is a personal content storage system designed for storing, syncing, and backing up digital assets. It functions as a distributed data synchronization engine and an S3 compatible backup tool, allowing users to persist data objects to cloud services for long-term preservation. The system utilizes a key-value content indexer to track data blobs for efficient retrieval and enumeration. It supports custom data modeling to define structures and relationships between stored information, moving beyond simple file storage. The platform includes capabilities for self-hosted content storage, pr

This project is a feature-rich Go client library designed for interacting with Redis. It serves as a comprehensive interface for managing remote data stores, enabling developers to execute standard database commands, handle complex data structures, and perform asynchronous operations within Go applications. The library distinguishes itself through its support for advanced Redis capabilities, including connection pooling, pipelining, and transactional integrity. It provides specialized primitives for managing distributed clusters, including automated topology updates and request routing to sha

Orioledb is a cloud-native storage engine for PostgreSQL designed to replace the default storage layer to improve vertical scalability and performance on modern hardware. It functions as an index-organized table store, organizing table rows directly within the primary index to accelerate data retrieval. The engine utilizes an undo log storage system to manage data versioning, which eliminates the need for manual vacuuming and prevents table bloat. It further reduces the disk footprint through block-level and page-level data compression. The project provides capabilities for advanced index ma

Bolt is a single-file embedded key-value store for Go applications. It is an ACID transactional database that organizes data in B+trees on disk to provide efficient sorted key retrieval and range scans. The system uses a memory-mapped model to map the database file directly into the process address space for fast random-access reads. The project distinguishes itself through a multi-version concurrency control architecture that allows multiple simultaneous readers to access a consistent snapshot of data without blocking a writer. It employs a single-writer multi-reader locking model and uses a

This project is a technical reference and a collection of internal analysis notes focused on the Go language runtime and compiler. It provides a detailed breakdown of the language internals, covering memory management, garbage collection, and the execution model of the scheduler. The material distinguishes itself by providing deep dives into low-level system details, including a reference for Go assembly instructions, register usage, and system call interfacing. It specifically analyzes the internal implementation of concurrency primitives, such as the goroutine scheduling mechanism, channel

RocksDB is a high-performance, embeddable persistent key-value library and storage engine based on Log-Structured Merge-trees. It is designed to provide durable storage for large-scale datasets, integrating directly into applications to manage data on flash and RAM-based hardware. The engine is distinguished by its focus on minimizing read and write amplification through multi-threaded compaction and custom memory allocators. It features specialized optimizations for flash storage, including support for zoned block devices, and provides the ability to extend store behavior via external plugin

FoundationDB is an ACID-compliant distributed transactional key-value store. It functions as a scalable database engine that ensures strict serializability and data consistency across a cluster of servers using a shared-nothing architecture. The system is distinguished by its multi-region replication capabilities, allowing data to be synchronized across different datacenters for high availability and disaster recovery. It utilizes optimistic concurrency control to manage distributed transactions and employs a majority-based coordination system to maintain cluster state. The platform provides

TablePro is a cross-platform database management client designed for browsing, querying, and administering both SQL and NoSQL databases. It functions as a unified workspace that integrates a code-centric SQL editor with schema visualization tools, allowing developers to manage complex data models and execute queries across diverse database engines. The application distinguishes itself through an agentic AI integration layer that connects language models directly to database tools, enabling automated query generation, optimization, and error fixing with configurable approval gates. It features

Lancet is a comprehensive extension of the Go standard library, providing a collection of reusable functions and data structures designed to reduce boilerplate code in applications. It serves as a general-purpose toolkit across multiple domains, including concurrency, security, networking, and functional logic. The project distinguishes itself through specialized toolkits for Go concurrency, such as keyed locking and channel-based stream processing, and a dedicated functional programming kit that supports currying and function composition. It also includes a dedicated cryptography library imp

Puter is a browser-based desktop environment and cloud-native development platform that provides a virtualized graphical workspace. It enables developers to build and deploy full-stack web applications by integrating cloud storage, authentication, and serverless backend logic directly into the browser, eliminating the need for traditional server infrastructure. The platform distinguishes itself through a unified cloud storage layer and a distributed network runtime that facilitates peer-to-peer communication and cross-origin resource fetching. It features a sophisticated cross-window orchestr

This project is a Chinese translation of a comprehensive guide to the Go programming language. It serves as a localized educational resource and technical manual designed to provide guidance on language syntax, design, and software development. The resource covers a broad range of Go language education, including the implementation of programming patterns and system design. It includes translated lessons and examples that focus on core language features such as concurrency and the use of interfaces. The content spans various capability areas, including language fundamentals, data modeling, r

open62541 is an open-source implementation of the OPC Unified Architecture standard, providing a complete stack for industrial automation and data exchange. It functions as both an OPC UA server and client, enabling the creation of an object-oriented address space to model physical industrial assets and their relationships. The project is designed for versatility across diverse hardware, offering a C99 library that can be deployed to both cloud servers and resource-constrained embedded environments. It distinguishes itself through a pluggable network layer and interface-based security backend

This project is a privacy-focused, self-hosted metasearch engine that aggregates results from a wide array of web, academic, and media sources into a single, unified interface. By acting as a proxy between the user and external search providers, it strips identifying headers and tracking parameters from requests, ensuring that search activity remains anonymous and protected from third-party profiling. The platform distinguishes itself through a modular, plugin-based architecture that allows for extensive customization of search behavior, result filtering, and interface branding. It supports a

This tool is a command-line processor designed for querying, updating, and transforming structured data files. It functions as a versatile engine for manipulating YAML, JSON, TOML, and XML documents, allowing users to perform complex operations directly from the terminal. By utilizing a path-based expression language, it enables precise navigation and modification of data structures within configuration files and infrastructure-as-code workflows. What distinguishes this tool is its ability to perform in-place document mutations while preserving original formatting, comments, and metadata. It

This project is a comprehensive collection of web development reference guides and technical cheat sheets. It provides a curated set of markdown-based documentation designed to help developers quickly locate syntax patterns and API examples for common web technologies and programming languages. The repository serves as a specialized reference library covering several distinct technical domains. It includes extensive guides for CSS, focusing on selectors, Flexbox, Grid, and responsive layout properties, as well as a DevOps command reference for Docker, Kubernetes, AWS, Ansible, and general she

Olric is a distributed data grid and in-memory key-value store that partitions and replicates data across a cluster of servers. It serves as a shared memory system for managing distributed maps, performing atomic operations, and acting as an in-memory data cache. The system provides a distributed locking mechanism for concurrency control and a pub-sub messaging system that broadcasts and routes messages over named channels across the cluster. The platform covers wide-ranging capabilities including cluster management and orchestration, data replication with configurable quorums, and automated

Store.js is a client-side state persistence library and web storage abstraction layer. It provides a consistent browser key-value storage wrapper that manages the persistence of application state across sessions using the most capable available local storage mechanism. The engine is extensible, allowing for the integration of custom storage backends and plugins to modify how data is read and written. It functions as a reactive web storage manager, monitoring specific keys to trigger notifications when stored values are updated. The library handles automatic data serialization for complex typ

FASTER is a high-throughput key-value store that combines an in-memory data store with a hybrid memory-disk storage engine, enabling datasets larger than available RAM. It uses a latch-free, cache-optimized index for concurrent point lookups and heavy updates, and records all mutations to a persistent append-only log on disk with checksum validation and group-commit checkpointing for crash recovery. The system supports multi-key transactional workloads through atomic multi-key locking, ensuring transactional consistency without coarse-grained contention. It exposes the key-value store to remo

Hive is a lightweight NoSQL key-value database written in pure Dart for local data persistence. It functions as a type-safe document store that allows for the saving and retrieval of complex data structures and custom objects. The system distinguishes itself through the use of custom adapters for object serialization and symmetric-key encryption to secure data at rest. For web environments, it provides a persistence layer that wraps IndexedDB and utilizes web workers. The project covers broad capability areas including container management, atomic transactional writes, and indexed data retri

LedisDB is a distributed NoSQL key-value store built in Go. It functions as a high-performance database server that persists simple values, counters, and complex data structures using pluggable storage engines. The system implements the Redis protocol to maintain compatibility with existing client libraries and drivers, while also providing an HTTP interface that exposes database functions through JSON, BSON, or msgpack formats. It includes an embedded virtual machine to execute custom server-side Lua scripts for complex operations. The platform supports high availability through data replic

DiceDB is a distributed cache manager and hierarchical storage engine based on a Valkey key-value store. It functions as a high-availability key-value cluster that balances performance and cost by distributing data across memory and disk tiers. The system supports working sets larger than available RAM by persisting evicted keys to disk and restoring them on demand. It also includes a real-time query subscription system that notifies clients when data matching specific criteria is updated. The project provides distributed cache coordination through master node health monitoring and quorum-ba

Godis is a Redis-compatible in-memory database and distributed key-value store. It functions as a replicated data store and distributed message broker, implementing the Redis protocol to manage complex data structures in memory. The system provides a geospatial indexing engine for proximity-based queries and distance calculations. It ensures high availability and data durability through master-slave replication and write-ahead logging. The project covers a wide range of capabilities including the management of strings, hash maps, lists, and sorted sets. It supports distributed data clusterin

This project is an asynchronous key-value store designed for client-side data persistence. It provides a unified interface that allows applications to save and retrieve complex data types, including binary objects, while maintaining responsiveness through non-blocking operations. By enabling offline-first functionality, it ensures that data remains accessible even when a network connection is unavailable. The library distinguishes itself through a driver-based abstraction layer that automatically detects the most efficient storage mechanism available in the current browser or mobile environme