Cube.js is a customizable analytics framework designed specifically for software engineers who need to embed analytics features into production, customer-facing applications. Its architecture is modular and scalable, allowing it to handle large datasets while providing full UI customization on the frontend. The framework's data schema is dynamic and JavaScript-based, enabling users to generate SQL code and apply OLAP best practices. Cube.js also provides pre-aggregations, a feature that enables the creation of reusable aggregate tables in warehouses, which are extremely fast to read. The client-side library abstracts the transport layer of loading data from the backend, handles loading and error states, and provides post-processing methods for metadata manipulation and visualization customization. With its modular design, Cube.js is suitable for various use cases, including serverless mode, and has a growing ecosystem of integrations, tutorials, and examples.