When using uv to build Python extensions via PEP 517 (e.g., maturin), ensure cache invalidation is keyed to the actual build inputs. Configure `tool.uv.cache-keys` so builds rerun only when the underlying sources for the compiled artifact change—especially Rust sources and Cargo manifests—rather than rebuilding whatever project owns the root `pyproject.toml`. Apply this by: - Adding Rust build inputs to `tool.uv.cache-keys` (e.g., `src/**/*.rs`, `Cargo.toml`, `Cargo.lock`, or the whole crate dir like `rustbpe/**`). - Including the crate in the workspace so uv associates changes with the correct package (e.g., `rustbpe = { workspace = true }`). - Verifying `uv sync` / `uv run` actually rebuilds the intended artifact when Rust code changes. Example: ```toml [tool.uv] # Invalidate build cache when Rust crate inputs change cache-keys = [ { file = "pyproject.toml" }, { file = "rustbpe/**" }, # alternatively, more targeted keys like: # { file = "src/**/*.rs" }, # { file = "Cargo.toml" }, # { file = "Cargo.lock" } ] # Ensure the crate is part of the workspace so the right package rebuilds [rustbpe] # (or in the relevant uv sources section) # rustbpe = { workspace = true } ```