Open Source

Ansible is an open-source automation platform that simplifies IT infrastructure management, application deployment, and configuration management through agentless, declarative automation. The tool ser

Apache Cassandra used by 30,000+ organizations worldwide as of September 2024. Open source under Apache Software Foundation, avoiding vendor lock-in. DataStax builds enterprise version (DataStax Enter

Apache CouchDB is open-source document-oriented NoSQL database implemented in Erlang, using JSON for data, JavaScript for MapReduce queries, and HTTP for API. Version 3.5.0 (May 2025): parallel reads

Cal.com is the open-source scheduling infrastructure for individuals, businesses, and developers. A Calendly alternative with full customization and self-hosting options.

Dagster Labs develops Dagster, an open-source data orchestration platform for building, deploying, and observing data assets. Founded in 2018 by former Facebook engineers Nick Schrock (GraphQL co-crea

dbt Labs develops dbt (data build tool), an open-source software platform that enables data analysts and engineers to transform data in their warehouses using SQL-based modeling and version control. T

Excalidraw is an open-source virtual collaborative whiteboard for creating diagrams, illustrations, flowcharts with hand-drawn aesthetic. Free open-sourced tool with paid Excalidraw+ tier (unlimited c

Fauna was a pioneering distributed serverless database company that revolutionized how developers approached data infrastructure from 2012 to 2025. Founded by ex-Twitter engineers Evan Weaver and Matt

Hugging Face is an AI platform and community that provides access to pre-trained machine learning models, datasets, and tools for natural language processing and other AI tasks. The company serves AI

Jenkins is an open-source automation server that enables developers to build, test, and deploy software through continuous integration and continuous delivery pipelines. The company serves software de

Kubernetes is an open-source container orchestration platform originally developed by Google and now maintained by the Cloud Native Computing Foundation. The platform automates the deployment, scaling

Mattermost is the open-source Slack alternative providing secure collaboration for high-security enterprises, government agencies, and technical teams. Offers self-hosted and private cloud deployments

Metabase is an open-source business intelligence platform that enables teams to create dashboards, visualizations, and reports through both no-code interfaces and SQL queries. Founded in 2014, the com

Mistral AI is Europe's leading AI foundation model company. €60M revenue projected for 2025 (5x from €10M in 2023), €11.7B valuation in 2025, €2.8B total funding. €300M annual contract value secured w

Moodle is the world's most widely-used open-source learning management system, providing a flexible platform for online courses, blended learning, and educational content delivery. The software enable

Prebid is an open-source header bidding solution that enables publishers to manage multiple demand sources simultaneously for their digital advertising inventory. The platform allows publishers to max

Prefect is a Python-based workflow orchestration platform that empowers data teams to build resilient, adaptable data pipelines. Founded in 2018 by Jeremiah Lowin, Prefect has raised $46.1M total fund

Prometheus is an open-source monitoring and alerting toolkit designed for reliability and scalability in cloud-native environments. The system collects and stores metrics as time-series data, provides

Redis is an in-memory data structure store with $209.8M revenue in 2024 (up from $154.2M in 2023) and $2B+ valuation from April 2021 Series G. Known for caching, real-time analytics, and messaging. 8,

RudderStack is a warehouse-native customer data platform that enables companies to collect, transform, and deliver real-time customer event data while maintaining full data ownership and privacy contr

YC W23; 700K+ users; Free storyboarding software; Filmmaker tools; Easy-to-use interface; YC Winter 2023

Terraform is an open-source infrastructure as code tool developed by HashiCorp that enables developers and operations teams to define, provision, and manage cloud infrastructure through declarative co

Travis CI is a continuous integration platform acquired by Idera on January 23, 2019 (via Cascadia Capital). Founded 2011, Berlin headquarters. 2024 revenue: $3.8M; 33 employees. Total funding: $135K

Twenty is a Paris France-based open-source CRM company founded in 2024 by Félix Malfait Charles Bochet Thomas Colas des Francs building Salesforce alternative raising $5.5M total funding including $5M

Vocode is a United States-based voice AI company founded in 2023 by Kian Hooshmand and Ajay Raj building open-source voice AI library raising $3.75M total funding including $3.25M seed February 2024 f