What is NeoScrypt?

NeoScrypt is a memory-hard proof-of-work algorithm designed as an improved successor to the original Scrypt algorithm. Developed by John Googler (Ghostlander) in 2014, NeoScrypt addresses several limitations of Scrypt while maintaining its memory-hard properties. The algorithm combines elements of Salsa20/20 and ChaCha20/20 stream ciphers with BLAKE2s hashing in a two-phase approach: first generating a large memory buffer through iterative mixing, then performing a series of dependent lookups within that buffer. This design requires approximately 128 KB of fast memory per thread, striking a balance between memory hardness and computational efficiency.

NeoScrypt offers several improvements over original Scrypt in terms of security and mining fairness. Its memory requirements are tuned to be particularly effective at resisting ASIC development while remaining efficient on consumer GPUs, creating a more level playing field for everyday miners. The algorithm provides stronger cryptographic properties than Scrypt by incorporating more modern primitives like BLAKE2s and ChaCha20. NeoScrypt also features better resistance to time-memory trade-off attacks, where miners might attempt to use less memory at the cost of increased computation — a known weakness in Scrypt's original design. The algorithm achieves approximately 2-3 times higher throughput on GPUs compared to Scrypt with similar memory requirements.

NeoScrypt was first adopted by Feathercoin, which migrated from Scrypt to NeoScrypt in late 2014 to combat the growing ASIC dominance in Scrypt mining. This transition demonstrated NeoScrypt's viability as a practical mining algorithm and encouraged adoption by other projects. Notable cryptocurrencies using NeoScrypt include Feathercoin, Phoenixcoin, GoByte, Innova, Trezarcoin, and Orbitcoin. While NeoScrypt never achieved the same level of mainstream adoption as Scrypt or Ethash, it carved out a niche among communities that valued GPU-accessible mining and served as an important example of iterative algorithm improvement in the cryptocurrency space.