Nucleo is a strongly typed and predictable state container library for JavaScript ecosystem written in TypeScript. JavaScript is a really dynamic language which we can't always rely in the language resilience from types perspective. Every project has types problems and developers can not make sure all the time the data is predictable. Inspired by how GraphQL does a great job with safety and trustful data and Redux by its simplicity on storing state, Nucleo was idealized to make sure the data model (contracts) and the data types are expected and reliable.