But why rewrite a 4M LOC system that works in a new language, just because of a new shiny? How do you justify that from a business standpoint? Especially when y

But why rewrite a 4M LOC system that works in a new language, just because of a new shiny? How do you justify that from a business standpoint? Especially when your current engineering staff are already experts in the currently used technology, but likely novices or mediocre in Rust? Do you freeze new features during the rewrite? Do you develop new features in parallel? Rewriting, just because, Rust, is a waste. Sure, you can hire new talent that knows Rust, but how long for them to pick up the relevant domain knowledge? How long for the existing talent that has the domain knowledge to become equivalently proficient in their current tech stack? Plus, with a rewrite, you risk falling ill to second system syndrome. Economically and from a practical engineering standpoint, it seems to me that Dropbox is taking a very pragmatic approach. Gradually make working with the exist code easier rather than throwing the baby out with the bath water. I'm not hating on Rust, but this fervor to rewrite everything in Rust is obnoxious and often short sighted, in my opinion. If you're talking brand new, green field development, by all means, it should be considered.