> On one hand, Dropbox Desktop Client has just a few settings. On the other, behind this simple UI lies some pretty sophisticated Rust code with multi-threaded compression, chunking, and hashing. On the lowest layers, it is backed up by HTTP/2 and TLS stacks.

And I found another Dropbox blog post about rewriting their sync engine from Python to Rust: https://dropbox.tech/infrastructure/rewriting-the-heart-of-o...

But it isn't clear whether the outer shell of the app might still be Python.