shiv is a command-line utility for building fully self-contained Python zipapps (PEP 441) that include all dependencies. It uses pip to install packages into a temporary directory, then packages the site-packages directory along with a bootstrap script into a single executable .pyz file. At runtime, the bootstrap extracts the dependencies to a cache directory (default ~/.shiv) and adds them to sys.path before executing the specified entry point or dropping into an interactive interpreter. The architecture is a CLI tool built with Click, orchestrated by a main module that delegates to pip and a custom zip archive builder. Key components include a robust environment configuration system that supports build-time settings and runtime overrides via environment variables, a cross-platform file lock for safe extraction, and a clean bootstrap pipeline. The codebase is well-structured, with comprehensive tests and support for Python 3.8+. It is maintained by LinkedIn and is actively used for distributing Python applications.