PGPy

PGPy is an open-source Python library that implements the OpenPGP standard as defined by RFC 4880. It allows developers to create, parse, sign, encrypt, decrypt, and verify OpenPGP messages directly within Python programs without requiring the GnuPG binary. The library is written in pure Python and is distributed under the BSD-3-Clause license.

The project was started to fill a gap in the Python ecosystem; earlier attempts such as pgpy2 were discontinued, and popular wrappers like python-gnupg relied on external GnuPG installations. PGPy provides a language‑native implementation, which makes it suitable for environments where installing GnuPG is problematic or where developers prefer to keep all dependencies within a virtual environment.

Key features include support for key generation, algorithm negotiation, keyrings, and a comprehensive test suite that covers file and stream I/O. It supports widely used algorithms such as RSA, ElGamal, DSA/DSA-ES, and ECDSA, and can handle symmetric key encryption with AES‑256, 3DES, and CAST5. The library also offers a high‑level API for creating PGP messages, adding signatures, and verifying signatures, which hides most of the low‑level packet handling.

Typical usage follows the pattern: load or generate a key with `PGPKey.new()`, create an `PGPMessage`, then encrypt with `encrypt()` or sign with `sign()`. The resulting message can be serialized to ASCII armor or binary form for storage or transmission. Verification is performed with `verify()`, which returns a `PGPSignature` object containing the signer's fingerprint, hash algorithm, and signature validity.

PGPy is actively maintained by a small core team and community contributors. Its documentation, extensive example scripts, and compatibility with Python 3.8 and newer make it a popular choice for projects needing end‑to‑end OpenPGP support without external dependencies.