Open-source Aiven alternatives

Redis is an in-memory data store that developers use as a cache, a session store, a database and a message broker. Because data lives in memory it answers requests quickly, which makes it popular for real-time applications. The project describes itself as a cache, a data structure server, and a document and vector query engine.

Rather than just strings, it offers data structures such as lists, sets, hashes, sorted sets and JSON, with higher-level patterns built on them, such as counters, queues, leaderboards and rate limiters, plus transactions and scripting. For caching it offers multiple eviction policies along with expiry for keys and for individual hash fields. It also handles key-value, document and time series storage, vector search and messaging. Client libraries cover most languages, and redis-cli and Redis Insight provide command line and graphical access.

The source is on GitHub, written in C, and can be built from source with documented flags for allocators, TLS and more. The license is listed as 'Other' in repository metadata, so check the current terms. Redis can be run on your own servers or consumed as a cloud-hosted service from the vendor.

ClickHouse is an open-source database management system built to generate analytical reports in real time. Its column-oriented storage makes scans and aggregations over very large tables efficient, which is why it is widely used for event data, logs, metrics and product analytics. It is written in C++ and queried with SQL.

The project's topics describe it as an OLAP, massively parallel and distributed system, and it is used for big data workloads where query latency matters. You can install it on Linux, macOS or FreeBSD, follow a tutorial that sets up a small cluster, or skip installation by trying ClickHouse Cloud, a managed service built by its creators. Releases arrive monthly, with a community call for each one, and there are Slack and Telegram channels for help.

ClickHouse is Apache-2.0 licensed. It is a good fit for analytics engineers and platform teams who need fast aggregations over billions of rows and are comfortable operating a database, or who prefer to hand that operation to the vendor's cloud.

Valkey is a distributed key-value database optimized for caching and other realtime workloads. It was forked from the open-source Redis project just before Redis moved to source-available licenses, and it continues as a community-driven alternative under the permissive BSD-3-Clause license.

It acts as a data structure server that mainly handles key-value workloads, supporting many native data structures along with an extensible module system for adding new structures and access patterns. The code is written in C and can be compiled with a simple make command on Linux, macOS, OpenBSD, NetBSD and FreeBSD, on both big and little endian and 32 and 64-bit systems. Support for Solaris-derived systems is limited and not guaranteed. TLS needs OpenSSL development libraries and can be built in or as a module.

The README is a quick-start only, with fuller documentation on valkey.io. Valkey is self-run software and is compatible with the Redis ecosystem of clients, so teams use it as a replacement for Redis in caching, session storage and queues when they prefer a fully open-source license.

PostgreSQL is a feature-rich object-relational database management system covering a large part of the SQL standard. Its feature set includes transactions, foreign keys, subqueries, triggers, and user-defined types and functions, and the distribution also contains C language bindings. This GitHub repository is only a mirror of the official git repository, written in C, and the metadata lists the license as Other.

The project does not use GitHub pull requests; contributors submit patches through the process described on the PostgreSQL wiki. Copyright and license terms are in the COPYRIGHT file, general documentation for each version is published on the project site, and build instructions explain how to compile the server from source. The latest releases of the software and related software are available from the PostgreSQL website. Many hosting providers offer managed PostgreSQL, but the project itself is software you install and operate.

MySQL is a widely used open-source relational database. This repository contains the MySQL Server source code along with MySQL Cluster, which the description presents as a real-time, open-source transactional database. Applications talk to it using SQL, and it is a common choice for web applications and embedded products.

The MySQL website describes several offerings built around the server: the Community Edition, with a published governance model and early access builds; MySQL Enterprise Edition for advanced features, management tools and technical support; MySQL HeatWave, a cloud service that combines transactions with analytics and machine learning; and MySQL Cluster CGE. A program for OEM and ISV vendors covers embedding the database in other products.

The server is written in C++ and distributed under licenses detailed in the repository. Organizations can run the Community Edition on their own infrastructure, buy a commercial edition from Oracle, which owns the project, or use a managed cloud offering. Documentation, downloads and a developer zone are available on mysql.com.

Apache Cassandra is an open-source, transactional, distributed NoSQL database. It is built to manage very large amounts of data across many machines, aiming for linear scalability and proven fault tolerance whether it runs on commodity servers or in the cloud, with no loss of performance. It is written in Java and developed under the Apache Software Foundation.

The project site presents Cassandra 5.0 along with documentation, a quickstart and community resources, and recent talks from the community cover topics such as Storage Attached Indexes, the Accord transaction protocol, mutation tracking, backups with Medusa, a sidecar process and analytics integrations. Cassandra is queried through CQL and can be run in clusters spanning racks, data centers or cloud regions.

Cassandra is licensed under Apache-2.0 and you run it yourself, either on your own servers or on cloud virtual machines or Kubernetes. It is typically chosen for write-heavy, always-on applications such as time-series data, messaging, IoT and large user-facing systems that must stay available when individual nodes fail.

CloudNativePG, often shortened to CNPG, is an open-source platform for running PostgreSQL databases on Kubernetes. Its core component is an operator that handles the whole operational lifecycle, from deployment to ongoing maintenance, in a way that fits GitOps-driven CI/CD automation.

It takes a Kubernetes-native approach to primary and standby cluster management. Rather than relying on external high-availability tools such as Patroni, repmgr or Stolon, the operator integrates directly with the Kubernetes API, and the status of a PostgreSQL cluster is exposed on the Cluster resource. It follows the operator pattern to reconcile the desired state, and application containers are immutable. Topics also list failover, switchover, replication, disaster recovery, a kubectl plugin, a Prometheus exporter and JSON logging.

CloudNativePG is a CNCF project written in Go and licensed under Apache-2.0, with a quickstart guide, governance policies, a list of adopters and pointers to commercial support. It is intended for Kubernetes administrators who want PostgreSQL managed as a native workload.

MariaDB Server is an open-source relational database built by a global community with the MariaDB Foundation and MariaDB plc. It started out as a MySQL fork driven by the people who created MySQL, keeps a high degree of MySQL compatibility, and is described as a straightforward migration target for existing MySQL deployments.

Since then it has gained its own capabilities. A native VECTOR data type with approximate nearest-neighbour HNSW indexing has been available since version 11.8. Pluggable storage engines include InnoDB, Aria and MyRocks, plus ColumnStore (analytics), Spider (sharding) and S3 (archiving). Replication options include async, semi-sync and parallel modes using global transaction IDs, and Galera provides synchronous multi-primary clustering. On the SQL side it offers common table expressions, window functions, temporal tables with system versioning, sequences and a range of JSON functions.

It also offers an Oracle SQL mode with PL/SQL-style routines, GIS data types and full-text indexing, and security features such as role-based access control, pluggable authentication, data-at-rest encryption and TLS. MariaDB is written in C++ and licensed under GPL-2.0, and you run it on your own servers or in the cloud.

Autobase is an internal database platform for PostgreSQL that brings the managed database experience of a cloud DBaaS onto infrastructure you control. You build and operate production-grade PostgreSQL clusters with high availability, and the tool aims to simplify deployment, reduce operating costs and make database management approachable even for teams without deep database expertise.

It automates deployment, failover, backups, restore, upgrades and scaling, with Patroni topics indicating a proven high-availability foundation, and offers a web interface written in TypeScript on top of automation scripts. The documentation includes an architecture overview. It is the successor to what was previously a PostgreSQL cluster automation project.

Autobase is MIT-licensed and self-hosted, running on your own servers, virtual machines or cloud accounts. It suits platform teams and companies that want managed-database convenience without paying for a hosted service, and that are ready to operate the underlying machines.