Question: Is there a backend platform that allows me to build web apps quickly and efficiently, with features like AI interfaces and fine-grained authorization rules?

If you're looking for a backend platform that lets you build web apps fast and efficiently with features like AI interfaces and fine-grained authorization rules, Amplication is definitely worth a look. The open-source platform is geared for .NET and Node.js app development and uses AI to generate production-ready backends in minutes. It comes with full-featured GraphQL and REST APIs, role-based access control, microservices support and continuous Git sync. Amplication also comes with an automatically generated React Admin UI and supports both monorepo and polyrepo structures, so it's adaptable to different development needs.

Another good option is Contember, a no-code backend development platform that combines AI and open-source frameworks. It lets developers quickly set up custom software projects by specifying what they need in plain English. Contember has modules for different business operations, and there's no vendor lock-in since you can connect to other software with unlimited connections to its API. It's good for small and medium-sized businesses and developers who want to automate business operations and streamline processes with custom web apps.

Noodl is also worth a look. It's an open-source, AI-boosted low-code platform for rapid development of full-stack custom applications. Noodl has visual development, AI-generated building blocks and real-time data flow visualization. It can be easily connected to third-party services and APIs, making it a good option for prototyping, MVPs and scalable web apps that require a minimal amount of code.

For a more traditional, low-code approach, Backendless offers a full suite of tools to build and run high-performance apps with efficiency. It includes a visual UI builder, codeless logic for frontend tasks and direct API integration for easy data integration. Backendless supports responsive web and mobile apps, real-time database capabilities and flexible deployment options, so it's a good option for developers who need to deploy scalable apps quickly.