Suggestion: Remove Autofac from the MAUI templated project

[kfrancis]

In MAUI applications, particularly when targeting iOS, Autofac's reliance on dynamic proxy generation (via Castle.DynamicProxy) introduces a significant challenge. iOS prohibits certain dynamic runtime behaviors, including the use of System.Reflection.Emit, which Autofac depends on for proxy-based interception. This leads to runtime crashes, especially in release builds where platform restrictions and linker behaviors become stricter.

Why Remove Autofac from the MAUI Template:

1. Platform Restrictions (iOS):

iOS does not support dynamic code generation techniques such as System.Reflection.Emit, which are used by libraries like Castle.DynamicProxy (a core part of Autofac's interception features). When using Autofac with dynamic proxies, iOS applications can crash due to PlatformNotSupportedException.
These crashes often manifest in release builds, where optimizations and linker behavior are stricter, making the issue harder to identify and debug during development.

2. Limited Utility of Dynamic Proxies:

The primary feature Autofac provides for developers in the context of iOS is interception through dynamic proxies. However, with the platform restrictions in place, this feature is not usable in MAUI applications targeting iOS.
Developers would have to implement workarounds (such as conditional compilation or disabling dynamic proxy generation for iOS builds) to prevent these runtime issues, which adds complexity to the codebase and introduces potential platform-specific bugs.

3. Linker Issues and Code Size:

In release builds, MAUI uses aggressive linking to minimize app size, and this can result in the removal of types and methods that Autofac depends on, especially when dynamic proxying is involved. This leads to additional crashes that are difficult to resolve, requiring configuration of linker behavior through XML configuration files or custom build settings.
Removing Autofac from the MAUI template would simplify release builds and reduce the potential for linker-related runtime issues, ensuring that the template is as compatible as possible with all target platforms.

4. Simpler Dependency Injection Alternatives:

MAUI already provides robust, built-in dependency injection support through the default Microsoft.Extensions.DependencyInjection (MSDI) framework, which is fully compatible with iOS and does not rely on dynamic proxy generation.
For most applications, MSDI is sufficient for handling dependency injection, and its use avoids the platform-specific issues caused by Autofac’s dynamic proxy features. Transitioning from Autofac to MSDI would streamline the MAUI template, eliminate platform incompatibilities, and reduce complexity for developers.

5. Better Developer Experience:

Developers using the abp.io MAUI template expect cross-platform compatibility. Including Autofac, which introduces iOS-specific limitations, contradicts this expectation and leads to runtime issues that are not immediately apparent in development environments (especially when running in debug mode).
Removing Autofac from the MAUI template would lead to fewer platform-specific issues and ensure a smoother development experience across all target platforms, particularly iOS.

Conclusion:
Removing Autofac from the MAUI template would eliminate the need for complex workarounds and prevent runtime issues caused by iOS’s platform restrictions. Given that MAUI and .NET's built-in dependency injection are sufficient for most applications, switching to the default DI framework would simplify the development process, enhance cross-platform compatibility, and improve the overall developer experience.