Ports and Adapters Clean Architecture Onion Architecture

Allow an application to equally be driven by users, programs, automated test or batch scripts, and to be developed and tested in isolation from its eventual run-time devices and databases.

Use Hexagonal Architecture pattern when

• it is important that the application is fully testable
• you use Domain Driven Design methodology and/or Microservices architectural style

• Apache Isis

• Alistair Cockburn - Hexagonal Architecture