Emissary

Uses LambdaMetafactory for direct method invocation, avoiding reflection and achieving up to 1000% more throughput compared to libraries like Spring's ApplicationEventPublisher, as shown in the benchmark links.

Integrates with Spring, Guice, and Jakarta CDI via the InstanceProvider interface, allowing handlers to be fully managed by DI containers with lifecycle hooks like @PostConstruct.

Supports custom annotations for handlers, enabling use in domain layers without adding library dependencies, as detailed in the 'Custom Request/Event Handler Annotations' section.

The core library has zero external dependencies, reducing bloat and version conflicts while maintaining simplicity, as emphasized in the philosophy.