# The Distributed Schema Problem [[Schemas define the shape of data|Schema exists to define the shape of data]]. Schemas get distributed across various computing systems, which causes challenges: schemas can get out of sync with one another, data can get persisted in one schema version and need to be read by a different schema version. ## External References - [Project Cambria talk at Fission](https://youtu.be/sCj4uRoefKw?si=x-LvYRrcZ8FD8Evc) - [Schema Negotiation at BlueSky](https://archive.org/details/27-09-45_schema_negotiation.qt) - AtProto's Lexicon (schemas): [Guide](https://atproto.com/guides/lexicon) and [Specs](https://atproto.com/specs/lexicon) - Revisit [Live & Local Schema Change: Challenge Problems](https://arxiv.org/abs/2309.11406) ## Open Question - How do schemas relate to [[A protocol is a specification describing the behavior of a software system|protocols]]?