1. Performance: One key difference between Dubbo and Jooby is their performance. Dubbo is designed for high-performance RPC (Remote Procedure Call) communication between services, focusing on low latency and high throughput. In contrast, Jooby is a modern web framework for building RESTful services, which may not prioritize high performance as Dubbo does.

2. Communication Protocol: Dubbo primarily uses the built-in TCP protocol, which is known for its reliability and low-level control over communication. On the other hand, Jooby commonly utilizes HTTP for communication, making it more interoperable with other systems that also rely on this protocol.

3. Service Communication Style: Another significant difference is the service communication style between Dubbo and Jooby. Dubbo follows a more traditional synchronous communication style, where the client waits for a response from the server before proceeding. In comparison, Jooby supports asynchronous communication, allowing the client to continue with other tasks while waiting for a response from the server.

4. Service Discovery: Dubbo has built-in support for service discovery and automatic load balancing, making it easier to scale and manage services within a distributed system. Jooby, on the other hand, may require external tools or configurations for service discovery and load balancing, adding complexity to the deployment and maintenance process.

5. Community Support: Dubbo has a well-established community with extensive documentation, resources, and active contributors, providing users with a strong support system for any issues or questions they may encounter. Jooby, being a newer platform, may have a smaller community and fewer resources available for users seeking assistance or guidance in their development process.

6. Framework Focus: Lastly, Dubbo is primarily focused on facilitating communication between services in a microservices architecture, with features tailored towards this specific use case. In contrast, Jooby caters to a broader range of web development needs, offering a more versatile framework for building various types of web applications beyond just microservices.

In Summary, Dubbo and Jooby differ in terms of performance, communication protocol, service communication style, service discovery, community support, and framework focus, catering to distinct use cases and development preferences.