Apache Dev List Digest: Iceberg, Polaris, Arrow & Parquet (Dec 9th - Dec15th, 2025)

Source: Dev.to

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• Apache Iceberg: The Definitive Guide
• Apache Polaris: The Definitive Guide
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• The Apache Iceberg Digest: Vol. 1

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Apache Iceberg

Patch Release 1.10.1 in Progress

Iceberg is preparing a 1.10.1 patch release. The initial RC0 vote was canceled after licensing issues were identified in certain module JARs. A new release candidate (RC1) was proposed on December 14 and is currently under vote as the official 1.10.1 release. This minor version aims to deliver critical bug fixes and stability improvements for the 1.10.x branch.

Impact – Once approved, the 1.10.1 update will provide production users with important fixes (e.g., dependency license corrections and runtime stability tweaks), ensuring a smoother experience on the latest Iceberg 1.x line.

December Board Report & Community Updates

The Iceberg team shared a draft of its December board report on the dev mailing list. The quarterly report outlines recent progress (such as the pending 1.10.1 release and Format V4 design work) and celebrates community growth, noting several new committers and PMC members added in the last quarter. The report helps Apache leadership oversee Iceberg’s health and momentum.

Iceberg Summit 2026 – Call for Papers

An [ANNOUNCE] invited talk submissions for the inaugural Apache Iceberg Summit 2026. The call for papers (CFP) is open until January 18 2026. The conference will showcase the project’s growing ecosystem and user community.

Why it matters – A standalone Iceberg Summit underscores the project’s maturation and broad interest, offering a forum for real‑world use cases, integrations, and best practices.

Multi‑Table Transactions Planning

Design discussions continue around supporting multi‑statement transactions that span multiple tables in Iceberg. Contributors are exploring an “Interactive Commit” API to coordinate atomic changes across tables (useful for complex ETL or schema‑evolution scenarios). A community sync call was scheduled for December 18 to refine the proposal and gather feedback.

Use case – If implemented, this feature would enable atomic commits across multiple Iceberg tables (e.g., updating a fact table and its derived aggregate table together), preserving consistency in all‑or‑nothing data workflows.

Apache Polaris

1.3.0‑incubating Released

Polaris (incubating) has officially shipped version 1.3.0‑incubating after passing the community vote on its release candidate. Highlights include:

• Generic Table GA – The “generic table” feature is now production‑ready, allowing Polaris to catalog external table formats (e.g., Apache Hudi, Delta Lake) in a stable way.
• Cloud Integration Improvements – Strengthened integration tests and fixes for cloud environments (AWS, Azure), improving reliability.
• Bug Fixes – Numerous reliability enhancements to core services.

As an incubating project, Polaris secured IPMC approval for the release, moving it closer to graduation.

New Backend: Google Spanner Support Proposed

A discussion was started to add Google Cloud Spanner as a backend option for Polaris’s catalog/storage layer. The proposal outlines integrating Spanner as a supported metadata store or transaction backend.

Benefit – Spanner integration would broaden Polaris’s multi‑cloud story beyond Hadoop/Hive metastores, simplifying deployments in GCP environments and supporting a wider range of data stores.

Incubator Report & Community Growth

Polaris prepared its December Incubator report, highlighting recent progress and community momentum. The report notes the successful 1.3.0 release, improved release automation, and helps mentors track readiness for graduation.

• Leadership update – Yong Zheng joined the Polaris PPMC, indicating growing contributor engagement.
• Community activities – Regular sync meetings continued (e.g., Dec 11) and a virtual development sprint was scheduled for Dec 16 to focus on onboarding, documentation, and open issues.

Apache Arrow

Arrow Go 18.5.0 Released

The Arrow Go subproject released version 18.5.0, a minor update comprising 38 commits from 17 contributors. The vote passed cleanly, and the release was announced on December 12.

Why it matters – The Go implementation is widely used in lightweight analytics and ETL pipelines. Regular updates keep Arrow’s Go support on par with its C++, Rust, and Java siblings, ensuring multi‑language consistency.

Release vote thread

Arrow Java 20.0.0 – Delayed for IP Clearance

The proposed Arrow Java 20.0.0 release was temporarily paused due to an IP clearance requirement involving a third‑party contribution. While the community supports the release in principle, Apache policy mandates formal review before new dependencies are included.

Takeaway – This demonstrates the ASF’s commitment to license transparency and compliance. Once clearance is approved, Arrow Java 20.0.0 is expected to proceed, bringing new features and performance optimizations for Java‑based analytics engines.

New TimestampWithOffset Type Approved

The Arrow format specification was officially extended to include a new TimestampWithOffset type. This provides a standardized way to represent timestamps with time‑zone offsets, eliminating ambiguity when sharing or serializing time‑based data.

Impact – The addition enhances time‑zone correctness across Arrow‑based data interchange.