This week, I ran into a problem. I was working on a client project, and as I was building a derivation, it took a loooong time to download substitutions from the configured binary caches. Now, the derivation in question has many input derivations for reasons that may become clearer in a future blog post. That being said, according to my betters at Numtide, the Nix daemon should pull them down from the binary caches with a reasonable degree of concurrency.
