May 2026

DuckDB Community Extensions: Rusty completed a maintenance cycle across multiple community extensions, bumping versions for airport, datasketches, bitfilters, geosilo, textplot, and lindel. This work was followed by six corresponding PRs on duckdb/community-extensions that update each extension to their latest commits — PR #1862 through PR #1866. These updates keep the extension ecosystem current with upstream development.

DuckDB Core: The focus shifted to performance and correctness issues in the query engine. He opened PR #22445 to fix a correctness regression in Arrow extension propagation for nested appenders. The issue (opened as #22444) involved BOOLEAN children of UNION types becoming corrupted under arrow_lossless_conversion = true; the fix addresses the same root cause across all container appenders (UNION, STRUCT, LIST, MAP, ARRAY) and targets the v1.5-variegata branch.

Parallel to the correctness work, Rusty tackled aggregate function performance with two optimization PRs. PR #22438 makes segment-tree fanout configurable per-aggregate, allowing tuning when combine and update operations use RPCs instead of in-process calls. PR #22437 defers segment-tree combine flushes across same-level parents in window functions, addressing the issue where the aggregate combine buffer is underutilized.

Apache Arrow: He provided community support by replying to issue #36388 regarding pyarrow.repeat returning invalid arrays when a chunked array is required.

Beyond the public repositories, Rusty also made 6 commits across 2 private repositories.