Gerard Marimon Caparrós

Gerard is a Java developer who keeps track of what changes between JDK releases and builds NextPatch, a short daily practice of Java version changes for working developers.

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Gerard Marimon Caparrós Oct 20, 2026 557 views

Upgrading from Java 21 to 25: What Actually Breaks

Seven changes between Java 21 and 25 that break builds, startup or behaviour, each reproduced on both JDKs, and how to find them before you …

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