This preview release of DuckDB is named "Mollissima" after the Common Eider (Somateria mollissima).
Binary builds are listed below. Feedback is very welcome.

Note: This release introduces a backwards-incompatible change to the on-disk storage format. We suggest you use the EXPORT DATABASE command with the old version followed by IMPORT DATABASE with the new version to migrate your data. See the documentation for details.

Major changes:

SQL

• #1847: Unify catalog access functions, and provide views for common PostgreSQL catalog functions
• #1822: Python/JSON-Style Struct & List Syntax
• #1862: #1584 Implementing NEXTAFTER for float and double
• #1860: FIRST implementation for nested types
• #1858: UNNEST table function & array syntax in parser
• #1761: Issue #1746: Moving QUANTILE

APIs

• #1852, #1840, #1831, #1819 and #1779: Improvements to Arrow Integration
• #1843: First iteration of ODBC driver
• #1832: Add visualizer extension
• #1803: Converting Nested Types to native python
• #1773: Add support for key/value style configuration, and expose this in the Python API

Engine

• #1808: Row-Group Based Storage
• #1842: Add (Persistent) Struct Storage Support
• #1859: Read and write atomically with offsets
• #1851: Internal Type Rework
• #1845: Nested join payloads
• #1813: Aggregate Row Layout
• #1836: Join Row Layout
• #1804: Use Allocator class in buffer manager and add a test for a custom allocator usage