cargo builds pyo3 bin with prefix /install, how to update?

[ClementWalter]

I have tried to set either PYO3_CROSS_LIB_DIR, PYO3_PYTHON, both from terminal or in my build.rs but I keep having this /install as prefix everywhere and consequently my bin not working.

I'm using

• mac os 15.3.2 on Apple M2.
• a venv managed by uv.
• pyo3 = { version = "0.23.4" }

my builds.rs looks like

use dotenvy::dotenv_override;
use std::env;

fn main() {
    if let Err(err) = dotenv_override() {
        eprintln!("Warning: Failed to load .env file: {err}");
    }

    // Build time dependencies
    if let Ok(lib_path) = env::var("LIBRARY_PATH") {
        println!("cargo:rustc-link-search={lib_path}");
        println!("cargo:rerun-if-env-changed=LIBRARY_PATH");
    }

    // Link time dependencies
    if let Ok(ld_library_path) = env::var("LD_LIBRARY_PATH") {
        println!("cargo:rustc-link-arg=-Wl,-rpath,{ld_library_path}");
        println!("cargo:rerun-if-env-changed=LD_LIBRARY_PATH");
    }

    if let Ok(dyld_library_path) = env::var("DYLD_LIBRARY_PATH") {
        println!("cargo:rustc-link-arg=-Wl,-rpath,{dyld_library_path}");
        println!("cargo:rerun-if-env-changed=DYLD_LIBRARY_PATH");
    }
}

when I run PYO3_PRINT_CONFIG=1 cargo b -p keth-run I see

  -- PYO3_PRINT_CONFIG=1 is set, printing configuration and halting compile --
  implementation=CPython
  version=3.10
  shared=true
  abi3=false
  lib_name=python3.10
  lib_dir=/install/lib
  executable=/Users/clementwalter/Documents/kkrt-labs/keth/.venv/bin/python
  pointer_width=64
  build_flags=
  python_framework_prefix=
  suppress_build_script_link_lines=false

so here I already see this /install and I don't know where it comes from.

once built, using otools I see

otool -L target/release/keth-run
target/release/keth-run:
        /install/lib/libpython3.10.dylib (compatibility version 3.10.0, current version 3.10.0)
        /usr/lib/libiconv.2.dylib (compatibility version 7.0.0, current version 7.0.0)
        /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1351.0.0)

if then I try to run, it fails

dyld[41034]: Library not loaded: /install/lib/libpython3.10.dylib
  Referenced from: <7D8217ED-521B-3870-B777-1DAFA99B7940> /Users/clementwalter/Documents/kkrt-labs/keth/target/debug/keth-run
  Reason: tried: '/install/lib/libpython3.10.dylib' (no such file)

if I export the DYLD path export DYLD_LIBRARY_PATH=$HOME/.local/share/uv/python/cpython-3.10.15-macos-aarch64-none/lib

it actually starts but raises and again I see all these /install prefixes

Could not find platform independent libraries <prefix>
Could not find platform dependent libraries <exec_prefix>
Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]
Python path configuration:
  PYTHONHOME = (not set)
  PYTHONPATH = (not set)
  program name = 'python3'
  isolated = 0
  environment = 1
  user site = 1
  import site = 1
  sys._base_executable = '/Users/clementwalter/Documents/kkrt-labs/keth/target/debug/keth-run'
  sys.base_prefix = '/install'
  sys.base_exec_prefix = '/install'
  sys.platlibdir = 'lib'
  sys.executable = '/Users/clementwalter/Documents/kkrt-labs/keth/target/debug/keth-run'
  sys.prefix = '/install'
  sys.exec_prefix = '/install'
  sys.path = [
    '/install/lib/python310.zip',
    '/install/lib/python3.10',
    '/install/lib/lib-dynload',
  ]
Fatal Python error: init_fs_encoding: failed to get the Python codec of the filesystem encoding
Python runtime state: core initialized
ModuleNotFoundError: No module named 'encodings'