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Backend Engineering

Java and Spring Boot in production. Microservices, Kafka, REST APIs, and the tradeoffs behind backend systems that stay reliable under load.

1 article

Isometric stack of framework layers rising from Spring Boot 3 to Spring Boot 4, the build, persistence, security and framework layers glowing in an aurora of emerald, cyan and violet against a dark background.

Backend Engineering

Upgrading a production service from Spring Boot 3 to Spring Boot 4

Spring Boot 3 to 4 migration, from a real production upgrade: the BOM cleanup, the code and test breaks, Hibernate 7, and the Spring Cloud Gateway and Netty trap.

27 June 2026 · 21 min