Apache Arrow dev list digest (Sept 1–5 2025)

Results of two key votes

Go v18.4.1 RC0 approved – On Sept 3 Matt Topol announced the outcome of the vote to release Apache Arrow Go v18.4.1 RC0. The vote passed with four binding +1s and one non‑binding +1. Matt thanked Dewey Dunnington, Sutou Kouhei, Gang Wu and himself for their binding votes and Jean‑Baptiste Onofré for a non‑binding vote. He then started the steps to publish the release. (thread)
Canonical Variant extension adopted – Matt Topol also reported that the vote to add a canonical variant extension type to the Arrow specification passed. Ten binding +1s (from Antoine Pitrou, Rok Mihevc, Jacob Wujciak, Ian Cook, Micah Kornfield, Sutou Kouhei, Gang Wu, Curt Hagenlocher, Dewey Dunnington and Matt himself) and one non‑binding +1 were recorded. He noted that discussions around the implementation pull request would continue before the type is merged into the docs. (thread)

Ongoing vote to add a variant extension type

Matt Topol opened a thread on Sept 1 to propose the canonical variant extension type, linking to the design and implementations across Go, Rust and C++ and explaining that it would provide a standardized way to represent “variant” values in Parquet. Community members responded enthusiastically: Xuwei Fu, Antoine Pitrou, Rok Mihevc, Jacob Wujciak, Ian Cook, Micah Kornfield, Sutou Kouhei, Gang Wu, David Li, Curt Hagenlocher and Dewey Dunnington all cast +1 votes. The thread included discussion about naming conventions and future integration with other file formats. (vote thread)

Feedback and +1s for the Go RC0 vote

Jean‑Baptiste Onofré responded to the Go v18.4.1 RC0 vote with a non‑binding +1 and appreciation for the release management. Gang Wu gave a binding +1 but reported a transient failure in the TestCloseSession test; after re‑running, the test passed and he concluded it was not a blocker. No negative votes were recorded, and the conversation wrapped up quickly. (vote thread)

Erlang Arrow implementation IP clearance

Benjamin Philip asked about the process for transferring an existing Erlang Arrow implementation into Apache Arrow. Sutou Kouhei pointed him to the Apache Incubator’s IP clearance guidelines and the XML template that must be filled out. He provided an example from the Arrow Flight SQL ODBC project and requested that Benjamin complete the template so the community could review it. (thread)

Bug report: huge data issue in RLE stream

Michał Puczyński’s bug report from late August continued into September. On Sept 1 Antoine Pitrou replied, thanking Michał for raising the issue and asking for more detail: what symptoms occurred when writing large amounts of double data to Parquet, and whether it crashed or threw an exception. Antoine requested a stack trace and the code used to reproduce the problem, so that the community could investigate and provide a fix. (thread)

Takeaway

During the first week of September 2025, the Arrow dev list was dominated by votes and results: the Go v18.4.1 release candidate was approved and a new canonical variant extension type was adopted. Discussions around the variant type highlighted cross‑language collaboration, while follow‑up votes concluded smoothly. The community also provided guidance on IP clearance for bringing an Erlang implementation into the project and began investigating a Parquet RLE bug.