Scrypt

Scrypt is a password-based key derivation function (KDF) designed to be computationally intensive and memory-hard, making it resistant to brute-force attacks using specialized hardware like ASICs or GPUs. It was created by Colin Percival in 2009 as a secure alternative to earlier KDFs such as PBKDF2, primarily for hashing passwords and deriving cryptographic keys from low-entropy inputs. Scrypt is widely used in cryptocurrency systems like Litecoin for proof-of-work and in various security applications for password storage.

Also known as: scrypt, SCRYPT, scrypt KDF, scrypt algorithm, scrypt hash

Why learn Scrypt?

Developers should learn and use Scrypt when they need to securely hash passwords or derive keys in environments where resistance to hardware-accelerated attacks is critical, such as in cryptocurrency mining, password authentication systems, or any application handling sensitive user credentials. It is particularly valuable in scenarios where attackers might use custom hardware, as its memory-intensive design increases the cost and difficulty of parallel attacks compared to simpler hash functions.

Learning Resources

• docs: Scrypt Wikipedia Page
• docs: Scrypt Specification (Tarsnap)
• tutorial: Scrypt Tutorial on Cryptography I/O
• tutorial: Scrypt in Python (Real Python Article)