cube-js/cube

Cube Core is an open source semantic layer, a middle tier that sits between your databases and the tools or applications that query them. A semantic layer's job is to define business metrics, dimensions, and logic in one place (for example, what exactly "monthly active users" or "revenue" means for your organization) and then expose those definitions through standard APIs so that any BI tool, embedded analytics feature, or AI agent can use them consistently without each tool needing its own hardcoded SQL queries. The problem Cube Core solves is fragmentation: most business intelligence tools have their own proprietary semantic layer baked in, so metric definitions get duplicated and drift apart across tools. Cube Core decouples this layer and makes it reusable. It connects to SQL databases and cloud data warehouses including Snowflake, Databricks, BigQuery, Postgres, and query engines like Athena. Once connected, it exposes your data through REST, GraphQL, and SQL APIs with a built-in caching engine that delivers sub-second query responses even under high load. The quickest way to start is with Docker, a single command launches Cube Core locally, and a browser-based setup wizard guides configuration. You would use Cube Core when building embedded analytics into a product (dashboards inside your SaaS app), when you want a single source of truth for metrics shared across multiple BI tools, or when you want AI agents to have well-defined access to your business data. The backend is written in Rust and Node.js, and is licensed under Apache 2.0.