prebuilt-package

name	prebuilt-package
description	Install and verify a prebuilt Usd Optimize package (no source build, no repo.sh). Use for binary-drop deployments.
version	1.0.0
allowed-tools	Shell
metadata	{"author":"NVIDIA Corporation","tags":["install","deployment","package"]}

Installing a Prebuilt Usd Optimize Package

This skill covers consuming a published binary drop (e.g. usd_optimize_usd_<usd_ver>_py_<py_ver>@<version>.<platform>.release). It is not for building from source — for that, use the build skill or repo.bat build / repo.sh build.

OS-specific install walkthroughs (interpreter install, environment-variable syntax, virtual-env activation):

• Windows: docs/install-prebuilt-windows.md
• Linux: docs/install-prebuilt-linux.md

The notes below are platform-neutral and capture the load-bearing details.

What this skill covers

Search this doc for keywords like usdpy, PYTHONPATH, LD_LIBRARY_PATH, entry-point, register_all, analysisMode, nvidia_usd_validate, auditwheel to jump.

• What's in a prebuilt drop — directory layout (include/, lib/, python/, usdpy/).
• Prerequisites — interpreter / OS requirements.
• Smoke-check the install — minimal verification commands.
• What does NOT work in the drop — repo.sh, source rebuilds, dev driver scripts.
• Public API surface — what's importable.
• Purpose / Limitations / Troubleshooting — scope summary, scope boundaries, common failure modes (PYTHONPATH, libusd alignment, validator plugin auto-loading).

Companion skills: build (build from source instead), validators (run-time validator infrastructure), run-validators / run-operations (dev driver scripts that need a source build, NOT a drop).

What's in a prebuilt drop

Directory	Contents
include/	C++ public headers
lib/	Compiled core and plugin libraries (Windows: *.dll + *.lib; Linux: *.so) plus operation_mapping.json (small deprecated-name alias table for map_config(), not the operation catalog)
python/	usd_optimize.* Python bindings; bundled tests under python/tests/test.python/
usdpy/	OpenUSD Python runtime (pxr.*) — the package brings its own USD
extraLibs/	Third-party runtime libraries (Alembic, MaterialX, OpenSubdiv, TBB). Windows releases also ship the matching CPython runtime DLL (e.g. python312.dll for py_3.12). Linux releases do not bundle libpython3.X.so.1.0 — it must come from the interpreter install (see Linux guide).

No Python interpreter is bundled — the consumer supplies one.

Prerequisites

1. Python version must match the py_<ver> token in the package name. The bundled pxr extension modules link against a specific CPython ABI; loading them under any other Python version fails at import time. On Windows the failure surfaces as ImportError: Module use of python<XY>.dll conflicts with this version of Python.; on Linux it surfaces as undefined-symbol or version-mismatch errors from the dynamic linker. The matching interpreter is the consumer's responsibility — see the OS-specific guide above.
2. PYTHONPATH must include both python and usdpy. Missing usdpy produces ModuleNotFoundError: No module named 'pxr'.
3. The platform's library-search path must include both lib and extraLibs, set before the interpreter starts. That's PATH on Windows and LD_LIBRARY_PATH on Linux. The path is consulted at module-load time only — exporting it after the Python process is running has no effect; restart the interpreter.

Linux — libpython on disk vs ldconfig -p. Bundled pxr needs libpython3.X.so.1.0 from your interpreter; ldconfig -p only reflects the linker cache and can be stale. Verify with the snippet in docs/install-prebuilt-linux.md (Python prerequisites): set PYLIBDIR from sysconfig.get_config_var("LIBDIR"), ls there, and compare to ldconfig -p | grep libpython…. Interpretation: (1) no .so under PYLIBDIR → install shared libpython or rebuild Python with --enable-shared; (2) .so under /usr/lib or /lib (multiarch counts) but ldconfig -p empty → run sudo ldconfig once — avoid reinstall churn or redundant LD_LIBRARY_PATH when libs already sit in the default linker layout; (3) .so only under pyenv/conda-style prefixes → add that PYLIBDIR to LD_LIBRARY_PATH (conda activation usually does this).

Smoke-check the install

A short script that proves the bindings load and an op runs against an in-memory stage. Save as smoke_check.py and run with the matching Python:

import json
from usd_optimize.core import ExecutionContext, UsdOptimizeCore
from usd_optimize.core.scripts import standalone
from pxr import Usd, UsdGeom

core = UsdOptimizeCore.getInstance()
assert len(core.getOperations()) > 0

stage = Usd.Stage.CreateInMemory()
UsdGeom.Xform.Define(stage, "/World")
UsdGeom.Cube.Define(stage, "/World/c1")
UsdGeom.Cube.Define(stage, "/World/c2")
ok = standalone.execute_commands_from_json(stage, json.dumps([
    {"operation": "deletePrims", "primPaths": ["/World/c1"]},
]))
assert ok and sum(1 for _ in stage.TraverseAll()) == 2
print("OK")

If this prints OK the drop is healthy. Any positive op-registry count confirms the plugins loaded; the exact count varies by build.

What does NOT work in the drop

• repo.sh build / repo.bat test — repo.sh/repo.bat is not shipped. The README's "Quickstart" applies to the source repo, not to the binary drop.
• python/tests/test.python/run_discover.py — the bundled test_validators_*.py modules require PyPI usd-validation-nvidia (usd_validation_nvidia). Without it, imports fail before unittest runs. If any module fails to import, run_discover.py exits with code 1 without executing tests. Even with imports fixed, most modules still expect fixtures under tests/data. The self-contained cases in test_core_python_bindings.py (test_executionContext, test_executionContext_reportPath_roundtrip, test_executionContext_reportPath_survives_executeOperation, test_usdOptimizeCore, test_operation) match the smoke check above.

Public API surface

The supported entry point for standalone consumers is usd_optimize.core.scripts.standalone:

• execute_commands_from_json(stage, filepath_or_json) — runs a JSON list of {"operation": …, …} descriptors against a Usd.Stage. Returns bool (overall success).
• map_config(config) — applies the operation/argument renames in lib/operation_mapping.json so older configs keep working.
• get_output_paths(operation) / get_output_path_arrays(operation) — return [] in standalone mode (only meaningful inside Kit).

Operation keys accepted by execute_commands_from_json are the strings from UsdOptimizeCore.getInstance().getOperations() at runtime (count varies by build). Bundled tests under python/tests/test.python/ illustrate descriptor JSON for many operations. lib/operation_mapping.json is only a small backward-compatibility alias table for map_config(), not the full operation list.

Purpose

Stand up a working Usd Optimize install from a prebuilt binary drop — no source clone, no repo.sh/repo.bat, no compiler. Cover the layout of the drop, the strict interpreter / library-path requirements, the canonical smoke check, and the boundaries of the supported public API so consumers can integrate the package into their own pipeline without reaching for the dev tooling.

Limitations

This is a runtime / consumer skill, not a development skill. The following are intentionally out of scope:

• Source rebuilds. A drop has no repo.sh / repo.bat and no compiler toolchain. Use the build skill against a checkout instead.
• Dev driver scripts. tools/perf_validators/run.sh, tools/perf_operations/run.sh, and similar require a source tree with _build/<platform>/<config>/; they will not work against a drop.
• Most bundled tests. run_discover.py needs every test_*.py to import cleanly first; missing usd-validation-nvidia breaks the test_validators_*.py set immediately. Any import failure prevents the unittest phase. Use the smoke check above as the supported install verification.
• Mixing your own USD with the drop's usdpy. pxr and the C++ core must resolve to the same libusd build — point PYTHONPATH at the drop's usdpy and don't shadow it with another USD install.
• Non-published platforms. Drops are produced for specific platform/USD/Python combinations (encoded in the package name). Other combinations need a source build.

Troubleshooting

Symptom	Likely cause
At-import error naming a specific python<XY>.dll / libpython<XY>.so ABI mismatch	Interpreter version doesn't match the py_<ver> token.
Linux: ImportError: libpython3.X.so.1.0: cannot open shared object file	Compare PYLIBDIR/ls vs ldconfig -p per Linux prebuilt guide: often stale cache (sudo ldconfig), pyenv/conda needs LD_LIBRARY_PATH, or missing libpython install — see troubleshooting there.
Importing any pxr.* module fails to resolve a transitive native dependency (Windows: DLL load failed; Linux: cannot open shared object file)	Library-search path missing lib or extraLibs, or set after the process started.
ModuleNotFoundError: No module named 'pxr' or 'usd_optimize'	PYTHONPATH missing usdpy or python respectively.
getOperations() returns []	Plugin libraries in lib/ failed to load — wrong-platform package, antivirus quarantine, or library-search-path issue.