[mswphd]

you can try doing `cargo build --timings ...`. It will generate a report of how long each crate takes to compile etc. It sounds like you know that your final crate is the culprit, but this would let you confirm it.

If you suspect the issue is assembling all the files together (e.g. linking) you can see some advice on optimizing link speeds here

https://nnethercote.github.io/perf-book/build-configuration....

Note that there could be other causes of slow compilation of the final binary. For example, if you heavily use (especially procedural) macros, it's known to make compilation quite slow.