ParityDb is an embedded, persistent key-value store meticulously engineered for blockchain applications, excelling in efficiently managing blockchain state using the Patricia-Merkle trie structure. Designed with prioritized read performance to enhance blockchain transaction throughput, it supports universal key-value storage with an API that allows data partitioning into columns for organized transaction handling. The database integrates multiple concurrent reader support, serialized batch write operations, and atomic transaction application to ensure consistency and reliability, even amidst IO interruptions. Eschewing custom data caching mechanisms, ParityDb relies on OS page cache, hinging upon available system memory for optimal performance. Structural integrity is bolstered by a suite of 256 value tables for data storage, with advanced hash indexing that employs a dynamical mmap-backed probing hash table. ParityDb operations include reindexing to manage collision handling efficiently. Distributed under both the MIT and APACHE 2.0 licenses, ParityDb invites contributions under dual-licensing terms, fostering open-source collaboration.