OK; what about this approach?

OK; what about this approach?

Yeah I've always known I could just cold open a JSON file directly but the goal is to align with the same DI IConfiguration approach used to load literally everything else, that's well configuration.

EDIT

and in the end its really more about why Microsoft.Maui.Storage.FileSystem and other crucial low level subsystems aren't initialized as part of the build chain as soon as builder?.UseMauiApp<App>() is called. I can't be the only one that has needs to reach into the platform agnostic FileSystem during the MauiAppBuilder process

You said CoPilot is dreaming. I found "ConfigureAppConfiguration" and ".host" on several topics (GitHub, blog, maui doc, stackoverflow.

Maybe you could look into this and adding your "loading" at the right step in mauiBuilder, Filesystem will be ready. I am making this up, just an idea to test.

You said CoPilot is dreaming. I found "ConfigureAppConfiguration" and ".host" on several topics (GitHub, blog, maui doc, stackoverflow.

Maybe you could look into this and adding your "loading" at the right step in mauiBuilder, Filesystem will be ready. I am making this up, just an idea to test.

maybe I'm missing a reference but neither intellisense nor typing it manually resolves to anything

The github link is for a proposal that was closed as not planned

The blog is from 2021 and maybe that version did but I can tell you from SourceLink current MauiAppBuilder does NOT have that property public or otherwise

using System;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Logging.Abstractions;
using Microsoft.Maui.Dispatching;
using Microsoft.Maui.LifecycleEvents;

namespace Microsoft.Maui.Hosting
{
	public sealed class MauiAppBuilder
	{
		private readonly ServiceCollection _services = new();
		private Func<IServiceProvider>? _createServiceProvider;
		private readonly Lazy<ConfigurationManager> _configuration;
		private ILoggingBuilder? _logging;

		internal MauiAppBuilder(bool useDefaults) {}

		class MauiCoreInitializer : IMauiInitializeService{}

		public IServiceCollection Services => _services;
		public ConfigurationManager Configuration => _configuration.Value;
		public ILoggingBuilder Logging{}

		public void ConfigureContainer<TBuilder>(IServiceProviderFactory<TBuilder> factory, Action<TBuilder>? configure = null) where TBuilder : notnull	{}
		public MauiApp Build(){}
		private sealed class LoggingBuilder : ILoggingBuilder{}
		private void ConfigureDefaultLogging()	{}
		private sealed class NullLoggerFactory : ILoggerFactory {}
		private sealed class NullLogger<T> : ILogger<T>, IDisposable {}
	}
}

The documentation is referencing ConfigurationManager which I'm already using to load things during the build process (where the problem of FileSystem not being initialized happens), the problem is once a ConfigurationManager is built the result is a IConfiguration which does not have the ability to load more configuration after that, it can read what its already loaded but you can't do another .AddJsonFile() after the build process at least not with anything I've found

Finally the stack overflow is 3 years old one of the more recent answers links PR which is the PR for literally removing Host as a property and follow up answers reiterate it being used for embedded retrieval not external files

OK; you have more knowledge on this then me, so I can't help here. My last idea is, can this configuration be done later, for example on .Activated?