Here are the top 10+ backend technologies to know in 2024:

1. Node.js: JavaScript runtime for building scalable network applications.
2. Django: High-level Python web framework known for its simplicity and robustness.
3. Spring Boot: Java-based framework for creating stand-alone, production-grade applications.
4. Ruby on Rails: A powerful web application framework written in Ruby.
5. ASP.NET Core: Open-source framework by Microsoft for building modern, cloud-based apps.
6. Flask: Lightweight Python framework for microservices and simple web applications.
7. Laravel: PHP framework with elegant syntax and built-in tools for rapid development.
8. Express.js: Minimalist framework for Node.js, ideal for APIs and web applications.
9. FastAPI: Modern, fast (high-performance) Python framework for building APIs with automatic interactive documentation.
10. GraphQL: Query language and runtime for APIs that enables clients to request exactly the data they need.
11. Koa.js: A next-generation Node.js framework by the creators of Express, designed for a more expressive and robust foundation for web applications and APIs.
12. Gin: A high-performance, minimalist web framework for Go, known for its speed and efficiency.

These technologies are crucial for developing efficient, scalable, and modern backend systems in 2024.