Open-source alternatives to Tarantool

HyperDex is a scalable, searchable key-value store

Fast scalable time series database

go-cache is a thread-safe, in-memory cache library for Go that stores arbitrary objects with per-item expiration timestamps. It provides a concurrent key-value store where multiple goroutines can safely read and write shared cached data without external synchronization, using a mutex-guarded map for access control. The library distinguishes itself through its expiration management and optional disk persistence. Each cached item carries its own time-to-live, and a background goroutine periodically purges expired entries. The cache can serialize its entire contents to disk using Go's gob encodi

OpenTSDB is a distributed time series database and metrics engine designed for storing and managing massive volumes of high-cardinality system metrics. It functions as a data store and analytics platform that enables large-scale metric ingestion and infrastructure performance monitoring across a distributed cluster. The system distinguishes itself through a distributed storage abstraction that supports multiple backends such as HBase, Cassandra, and Google Bigtable. It utilizes a hierarchical metric tree to organize time series and employs numeric identifier indexing to reduce storage footpri

RoseDB is an embedded key-value database and log-structured storage engine. It functions as a library-based database that runs within an application process to provide local data persistence without the need for a separate database server. The project implements a Bitcask-style store, utilizing an append-only log format to maximize write throughput and minimize seek time. It ensures data consistency by grouping multiple read and write operations into single atomic units. The storage architecture relies on an in-memory key index for constant-time lookups and uses segment-based file management

etcd is a distributed key-value store and configuration store designed to maintain a consistent set of data across a cluster of nodes. It functions as a reliable registry for storing and synchronizing critical settings and metadata used by distributed applications. The system implements the Raft consensus algorithm to ensure data consistency and leader election across servers. To protect data transfers and verify node identities, it utilizes a network security layer based on mutual TLS and client certificates. Its capabilities cover distributed configuration management, cluster state synchro

Cayley is a graph database engine designed for storing and querying interconnected data using a quad-based data model. It functions as an RDF quad store, managing information through subjects, predicates, objects, and labels. The system features a modular graph store architecture with pluggable backends, allowing it to swap between in-memory storage and various external persistent databases. It includes a GraphQL-inspired API and a dedicated data visualizer for the interactive exploration of nodes and edges. Query capabilities cover bidirectional path traversal and multi-syntax execution usi

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

TiDB is a horizontally scalable, distributed SQL database designed to provide consistent transactional storage and high-performance analytical processing within a single unified architecture. It utilizes a decoupled compute-storage design and a distributed key-value storage layer to ensure horizontal scalability and efficient range-based queries. By employing a consensus-based replication algorithm, the system maintains high availability and automatic failover across multiple nodes and geographical regions. The platform distinguishes itself through its hybrid transactional and analytical proc

Pebble is an embedded key-value storage engine written in Go, designed as a library that provides durable, write-optimized data persistence directly within applications. It organizes data using a log-structured merge-tree (LSM-tree) structure, where writes are first buffered in an in-memory skiplist memtable and persisted to a write-ahead log before being flushed to block-based SSTable files on disk. The engine supports atomic batch commits, configurable write synchronization, and automatic background compaction that merges and rewrites sorted runs to reclaim space and maintain read performanc

Dice is a low-latency key-value store based on Valkey that functions as a hierarchical storage engine. It combines a high-speed memory store with a tiered cache system to manage data across multiple storage levels. The system extends memory capacity by implementing a disk-backed cache that automatically persists evicted items to disk and restores them during cache misses. This storage tiering balances retrieval speed and operational cost by distributing data between fast memory and slower disk storage. The engine includes a query subscription service that monitors specific data patterns and

This project is a full text search engine and enterprise search infrastructure designed for indexing and retrieving large sets of documents. It provides a comprehensive framework for information discovery using ranked results and linguistic analysis. The system integrates high-dimensional vector similarity search for semantic retrieval alongside traditional full-text capabilities. It distinguishes itself through support for geospatial data retrieval, multilingual text processing, and a search suggestion workflow that includes typo-tolerant query completion and spellchecking. The platform cov

Bloat-free, no BS cloud storage SDK.

Apache Druid is a real-time OLAP database and distributed analytics engine. It functions as a columnar time-series database designed for high-performance analytical queries and the real-time ingestion of streaming and batch datasets. The system provides a framework for high-concurrency analytics, allowing multiple simultaneous users to execute SQL and native queries across large-scale data. It supports mixed data ingestion, combining real-time streaming and batch loading into a single system for unified analysis. The platform includes capabilities for distributed cluster management, enabling

Ignite is a distributed in-memory data grid and compute platform. It functions as a distributed SQL database and storage engine designed to store and process large datasets in RAM to minimize latency and increase calculation speed. The system is distinguished by a multi-tier storage engine that manages data placement across memory and disk to balance high-speed access with large capacity. It features a distributed compute grid that executes custom logic directly on the nodes where data resides to reduce network traffic. The platform provides a broad set of capabilities including ACID transac

Alluxio is a virtual distributed file system and data orchestration layer that serves as a high-performance caching layer between cloud storage and compute clusters. It acts as a distributed data cache designed to accelerate data access for large-scale analytics and machine learning workloads. The system provides a unified interface that presents multiple heterogeneous storage backends as a single coherent namespace. This allows for the unification of diverse storage systems, enabling computation engines to access data from different providers without changing application code. The project c

Time-series database

An Erlang implementation of Redis

Apache Drill is a distributed MPP query layer for self describing data

Key Value Database in .Net with Object DB Layer, RPC, dynamic IL and much more

Codis is a distributed proxy system designed for scaling Redis clusters. It provides a sharding proxy that distributes data across multiple instances and a cluster manager to oversee the environment. The system enables horizontal scaling through dynamic resharding, which allows data slots to be migrated between servers without interrupting operations. It supports multi-key atomic operations using hash tags to ensure related keys are routed to the same server. The platform includes a graphical cluster management dashboard for monitoring and administration. It implements high availability prox

An in-memory cache library for golang. It supports multiple eviction policies: LRU, LFU, ARC

The official Couchbase SDK for .NET Core and Full Frameworks

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Cassandra is a distributed NoSQL database and wide-column store designed for high availability and linear scalability. It functions as a fault-tolerant distributed system that utilizes an LSM-tree storage engine to optimize write throughput and manage massive datasets. The system is a CQL-compliant database, using a structured query language to manage and retrieve tabular data stored across multiple nodes. It organizes information into rows and columns based on a flexible schema and primary keys. The project provides capabilities for horizontal database scaling, distributed data partitioning