As a MERN (MongoDB, Express, React, and Node.js) stack developer, the top 10 technologies and frameworks worth considering to learn in 2023:

1. GraphQL: It is a query language for APIs that enables developers to get exactly the data they need in a single request. It can be a useful skill to have as a MERN stack developer, especially for building scalable and efficient APIs. You can learn more about this here...

2. Next.js: Next.js is a popular React framework that offers server-side rendering, static site generation, and other advanced features. It can help improve the performance and user experience of your React applications. You can learn more about this here...

3. Docker: Docker is a containerization platform that enables developers to package and deploy applications as containers. It can be a useful tool for managing dependencies and simplifying the deployment process. You can learn more about this here...

4. Redux: Redux is a predictable state container for JavaScript apps that can help manage the state of your React applications. It can be a valuable skill to have as a MERN stack developer, especially for building complex applications. You can learn more about this here...

5. TypeScript: TypeScript is a typed superset of JavaScript that can help improve the maintainability and scalability of your code. It can be a useful skill to have as a MERN stack developer, especially for building large-scale applications. You can learn more about this here...

6. AWS Lambda: AWS Lambda is a serverless compute service that enables developers to run code without managing servers. It can be a useful tool for building scalable and cost-effective backend services. You can learn more about this here...

7. React Native: React Native is a popular framework for building mobile applications using React. It can be a valuable skill to have as a MERN stack developer, especially if you're interested in building mobile applications. You can learn more about this here...

8. Socket.io: Socket.io is a library that enables real-time, bidirectional communication between clients and servers. It can be a useful tool for building real-time applications, such as chat applications. You can learn more about this here...

9. Serverless Framework: Serverless Framework is a framework that enables developers to build and deploy serverless applications easily. It can be a useful tool for building scalable and cost-effective backend services. You can learn more about this here...

10. Jest: Jest is a popular testing framework for JavaScript applications. It can help ensure the quality and reliability of your code, and can be a valuable skill to have as a MERN stack developer. You can learn more about this here...