Spring Boot

Spring Boot is an opinionated framework built on top of Spring Framework that automates the configuration of Spring applications. Released in 2014, it replaced the XML verbosity of early Spring with convention-based auto-configuration: if a library is on the classpath, Spring Boot configures it automatically. The result is that a runnable web application can be created in a single file with no explicit configuration — a dramatic reduction in the cognitive overhead that once made Spring development as complex as the Enterprise JavaBeans it was designed to replace.

The framework's design philosophy — opinionated defaults with escape hatches — has become a dominant pattern in modern software development. Spring Boot makes the common case easy and the uncommon case possible, but the line between 'common' and 'uncommon' is drawn by the framework's authors, not by the developer. This is a form of paternalism that accelerates development for standard cases and constrains it for non-standard ones. The question is whether the constraints are visible to the developers who live within them.