Delay asset pipeline until rust build finished

My use case includes copying SCSS files through a libraries build.rs file into my application root directory.

Building the styles (SASS) will only work with the output from this build script.

But the asset pipeline always runs in parallel / can not be configured to run after a finished rust build. Errors in the SASS pipeline lead to a retry, also skipping/aborting the rust build, leading to no build.rs being executed an and endless retry-loop.

Could such an optional behavior be integrated into trunk?