Yup is a JavaScript object schema validator and object parser based on Joi
Yup is a JavaScript object schema validator and object parser. The API and style is inspired by Joi.
Yup is leaner than Joi: in the same spirit, without some of the fancy features. You can use it on the server as well, but in that case you might as well just use Joi.
Yup is also a good bit less opinionated than joi, allowing for custom transformations and async validation. It also allows "stacking" conditions via when for properties that depend on more than one other sibling or child property. Yup separates the parsing and validating functions into separate steps so it can be used to parse json separate from validating it, via the cast method.
Documentation and source can be found on the yup github page
