light-4j is aiming microservices and it has to be high throughput, low latency, light-weight and address a lot of cross-cutting concerns at the same time. It is based on Undertow Core Http server and depending on minimum third party libraries.

The topics here are architectural considerations. In a nutshell, architecture is a type of design where the focus is quality attributes and wide(er) scope whereas design focuses on functional requirements and more localized concerns. There is another section for design decisions.

Here is a list of architecture decisions for the framework:

  • Designed for microservices that can be dockerized and deployed within containers.

  • Base on pure HTTP without JavaEE as it has too many problems and is declining

  • Security first design with OAuth2 integration and distributed verification with embedded distributed gateway.

  • How to handler distributed transaction in microserivces.

  • All components are designed as plugins and the framework is easy to be extended and customized.

  • Can be integrated with existing application to protect investment over the year for your organization.

  • Support direct calls from microservice to microservice without any gateway, proxy as they add too much overhead.

  • Service logs will be aggregated with ElasticSearch, LogStash and Kibana with monitoring and alerting.

  • Built-in CorrelationId and TraceabilityId to trace service to service calls in aggregated logs.

  • Designed for scalability so that you can have thousands instances running at the same time.

  • Has its own dependency injection framework so that developers can avoid heavy Spring or Guice as they are bloated

  • Elements of API platform.

  • API category and how to choose a framework to build your APIs.