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Leviathan Crypto Library

A zero-dependency WebAssembly cryptography library. Two ciphers, opposite philosophies, same security properties.

npm install leviathan-crypto
# or
bun add leviathan-crypto

No bundler? No problem! See CDN usage.

AEAD

Seal, SealStream, OpenStream, and SealStreamPool are the primary API for authenticated encryption in leviathan-crypto. They are cipher-agnostic: you pass a CipherSuite object at construction and the implementation handles key derivation, nonce management, and authentication for you.

The classes form a natural progression:

• Seal handles data that fits in memory.
• SealStream and OpenStream handle data that arrives in chunks or is too large to buffer.
• SealStreamPool parallelizes the chunked approach across Web Workers.

All four produce and consume the same wire format, so a Seal blob can be opened by OpenStream and vice versa.

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