Yes, I am building a production Flutter desktop app for Deloitte that manages presentation document files. We just deployed a POC version into their infrastructure yesterday, and we have plans to share parts of the code with mobile app versions, etc.
I posted a question about supporting release builds on Windows and when that would be available in this forum. They love the app, and I am generally pleased with the results. I was even able to write a native code plugin to manage the arrangement of windows on the desktop that worked amazingly well based on the embedded desktop examples.
Now that the client is using it, though, we need to tighten it up pretty quickly. Any help or information you can provide would be fabulous.