Cube Core version 1.5 introduces several enhancements such as improved data model compilation performance, new API extensions, and support for calendar cubes in preview, without introducing breaking changes. Notable improvements include a 2-3x speedup in data model compilation, enhanced YAML and Python support, and expanded capabilities of the Tesseract data modeling engine. The release also boosts support for various data sources like Athena, Databricks, DuckDB, Presto, Snowflake, and Trino, with new features such as OAuth authentication and custom granularities. Enhancements to APIs include a new HTTP transport for the SQL API and explicit cache control in REST API endpoints. Pre-aggregation matching is refined to use the join tree structure, improving query performance, while Cube Store sees optimizations for memory usage and support for multi-stage calculations. Documentation updates provide expanded guidance on joins, and the release includes upgrades to Node.js and Python versions. The Cube team encourages feedback and testing in a staging environment before deployment, and users are invited to join their Slack community for support and updates.