Time to first build is quite high

[prrao87]

Trying to do the following on macOS Tahoe 26.2 (M4 pro) and it for the first time it's built, the uv add lance-graph command takes a very long time to complete (around 10 mins):

❯ uv add lance-graph --no-cache
Resolved 65 packages in 1.10s
   Building lance-graph==0.4.0
⠦ Preparing packages... (62/63)

Does this end up doing a single-threaded full build of the Rust crates every time it's installed on a new machine? Curious why it's so slow. Once it's installed the first time, the next one is quick because it's in uv's cache. Wondering if there's a way to distribute it with pre-compiled Rust crates for better UX.

[beinan]

Hi @prrao87 , you’re exactly right. Currently, uv add is falling back to a source distribution (sdist) because pre-compiled wheels aren't yet available for the M4/macOS Tahoe architecture.

By default, uv triggers a Release build to ensure runtime performance, which involves heavy optimizations and leads to that ~10-minute wait. For local development, I recommend using maturin develop. This will create a Debug build by default, skipping those optimization passes and significantly speeding up the compilation process.

[beinan]

The GitHub CI is running into the same issue as well — let me take a look and see if there’s anything we can do.

[prrao87]

Thanks Beinan! qq: Will running maturin develop with debug build affect performance for any benchmarks that I run? I know that release builds optimize heavily at the LLVM level, but I'm not sure if that translates to tangible performance differences at the Python level above. Considering that my goal is to get both benchmarks for lance-graph I prepared fully functional, I wonder if just using release builds is better for my case.