Best Free Semantic Layer Tools of 2025

dbt Labs is redefining how data teams work with SQL. Instead of waiting on complex ETL processes, dbt lets data analysts and data engineers build production-ready transformations directly in the warehouse, using code, version control, and CI/CD. This community-driven approach puts power back in the hands of practitioners while maintaining governance and scalability for enterprise use. With a rapidly growing open-source community and an enterprise-grade cloud platform, dbt is at the heart of the modern data stack. It’s the go-to solution for teams who want faster analytics, higher quality data, and the confidence that comes from transparent, testable transformations.

Kyvos is a semantic data lakehouse designed to speed up every BI and AI initiative, offering lightning-fast analytics at an infinite scale with maximum cost efficiency and the lowest possible carbon footprint. The platform provides high-performance storage for both structured and unstructured data, ensuring trusted data for AI applications. It is built to scale seamlessly, making it an ideal solution for enterprises aiming to maximize their data’s potential. Kyvos is infrastructure-agnostic, which means it fits perfectly into any modern data or AI stack, whether deployed on-premises or in the cloud. Leading companies rely on Kyvos as a unified source for cost-effective, high-performance analytics that foster deep, meaningful insights and context-aware AI application development. By leveraging Kyvos, organizations can break through data barriers, accelerate decision-making, and enhance their AI-driven initiatives. The platform's flexibility allows businesses to create a scalable foundation for a range of data-driven solutions.

Data engineers and scientists can be 95% better at their jobs with ready access to the most flexible semantic layer, explainable AI and reusable data modelling. They can create and expand semantic models, understand data interrelationships, and run federated query to speed up time to insight. Stardog's graph data virtualization and high performance graph database are the best available -- at a price that is up to 57x less than competitors -- to connect any data source, warehouse, or enterprise data lakehouse without copying or moving data. Scale users and use cases at a lower infrastructure cost. Stardog's intelligent inference engine applies expert knowledge dynamically at query times to uncover hidden patterns and unexpected insights in relationships that lead to better data-informed business decisions and outcomes.

Phoenix serves as a comprehensive open-source observability toolkit tailored for experimentation, evaluation, and troubleshooting purposes. It empowers AI engineers and data scientists to swiftly visualize their datasets, assess performance metrics, identify problems, and export relevant data for enhancements. Developed by Arize AI, the creators of a leading AI observability platform, alongside a dedicated group of core contributors, Phoenix is compatible with OpenTelemetry and OpenInference instrumentation standards. The primary package is known as arize-phoenix, and several auxiliary packages cater to specialized applications. Furthermore, our semantic layer enhances LLM telemetry within OpenTelemetry, facilitating the automatic instrumentation of widely-used packages. This versatile library supports tracing for AI applications, allowing for both manual instrumentation and seamless integrations with tools like LlamaIndex, Langchain, and OpenAI. By employing LLM tracing, Phoenix meticulously logs the routes taken by requests as they navigate through various stages or components of an LLM application, thus providing a clearer understanding of system performance and potential bottlenecks. Ultimately, Phoenix aims to streamline the development process, enabling users to maximize the efficiency and reliability of their AI solutions.

Cube serves as a comprehensive platform that establishes a universal semantic layer aimed at streamlining and consolidating the management and analysis of enterprise data. By revolutionizing data management practices, Cube removes the challenges associated with inconsistent models and metrics, thereby providing users with reliable data that is also primed for AI applications. This innovative platform is instrumental for organizations seeking to expand their data infrastructure by harmonizing various data sources and generating uniform metrics applicable across different teams. Tailored for enterprises, Cube enhances analytical capabilities, ensures data accessibility, and facilitates effortless access to AI-driven insights. With Cube, companies can navigate the complexities of data management more effectively than ever before.