Multi-threaded serialization of compressed array that fully utilizes modern solid state drives. It allows to store and load extremely large data on demand within seconds without occupying too much memories. With data stored on hard drive, a lazy-array data can be loaded, shared across multiple R sessions. For arrays with partition mode on, multiple R sessions can write to a same array simultaneously along the last dimension (partition). The internal storage format is provided by 'fstcore' package geared by 'LZ4' and 'ZSTD' compressors.