Event library
What's an event library, and how was the original Redis event library implemented?
Redis internals
Documents describing internals in early Redis implementations
The following Redis documents were written by the creator of Redis, Salvatore Sanfilippo, early in the development of Redis (c. 2010), and do not necessarily reflect the latest Redis implementation.
String internals
Guide to the original implementation of Redis strings
Virtual memory (deprecated)
A description of the Redis virtual memory system that was deprecated in 2.6. This document exists for historial interest.
Redis design draft #2 (historical)
A design for the RDB format written in the early days of Redis