libsodium

Libsodium is a portable, cross-platform cryptographic library designed to be easy to use and resistant to misuses. It provides a high-quality, well-audited implementation of a broad set of cryptographic primitives and is API-compatible with NaCl (the Networking and Cryptography Library), making it a convenient drop-in replacement for many NaCl-based projects. Libsodium is implemented in C and offers bindings for many programming languages, enabling use from Python, Java, JavaScript, Go, Rust, and more. The project emphasizes a simple interface, sensible defaults, and attention to side-channel resistance.

Core capabilities include authenticated encryption with high-level APIs such as crypto_secretbox and the crypto_aead family, public-key cryptography with crypto_box, and digital signatures with crypto_sign. It also provides password hashing via crypto_pwhash (including Argon2id-based algorithms) and a cryptographically secure random number generator. Libsodium aims to minimize common cryptographic mistakes by offering safe wrappers, constant-time operations, and explicit error handling. It also includes utilities for secure memory handling and key management.

Development and licensing: Libsodium is maintained by the Libsodium project with contributions from the open-source community. It is released under the ISC license, emphasizing permissive use in a wide range of software. Libsodium is widely deployed in applications requiring portable, reliable cryptography and is supported on major platforms, including Windows, macOS, Linux, and other Unix-like systems.