SafeOstruct is a fast, dependency-free struct-like class with an OpenStruct-style interface. Instances are built on cached per-key-set shape classes with real attr_accessor methods, so attribute reads and writes run at Struct speed (within ~10% of raw Hash access) instead of going through method_missing. It supports dynamic attributes, method-style and hash-style (symbol or string) access, and returns nil instead of raising NoMethodError for undefined attributes.