Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

[4.2.0] - 2026-07-13

🪄 Added

• Added automatic read/write splitting driven by SQL parsing via the new autoReadWriteSplitting and sqlParser plugins, which route statements to a reader or writer based on the parsed SQL (PR #1995).
• Added query-level load balancing for the autoReadWriteSplitting plugin so read traffic can be distributed across readers on a per-query basis (PR #2009).
• Added the awsSecretsManager2 plugin, which uses a stale-while-revalidate caching strategy to serve credentials from cache while refreshing them in the background (PR #1985).
• Added lowestLoadByCpu and lowestLoadByLag host selection strategy variants that default to CPU-dominant and lag-dominant weighting respectively (PR #1997).

🐛 Fixed

• Fixed the configuration profile not being propagated to eagerly-created topology monitors, which could leave those monitors without profile-configured plugins (Issue #2020, PR #2021).
• Fixed the custom endpoint monitor's throttling backoff being bypassed (PR #2014).
• Fixed an NPE caused by a check-then-act race in ImportantEventService#removeExpiredEvents (PR #1987).

🦀 Changed

• Adopted the Checker Framework NullnessChecker across the codebase to improve null-safety (PR #1981, PR #1998, PR #1999, PR #2007, PR #2008, PR #2010, PR #2015, PR #2018).
• Dependency updates, including PostgreSQL JDBC driver 42.7.13, Hibernate ORM 7.4.4.Final, Jackson (2.22.0 and 3.2.0), Kotlin 2.4.0, c3p0 0.14.1, Gradle Shadow plugin 8.3.11, and various GitHub Actions bumps (PR #2012, PR #2006, PR #2013, PR #2005, PR #2000, PR #1991, PR #1988, PR #1994, PR #1990, PR #2001, PR #2003, PR #2004, PR #2002, PR #1993, PR #1992).
• Documentation:
  • clarified internal and external connection pool stacking guidance (PR #2019)
  • documented the MariaDB driver Aurora pipelining caveat (PR #1984)
  • clarified setting wrapper properties via JDBC URL parameters (PR #1983)
  • added examples for specifying driver properties (PR #1982).