Rumale::ModelSelection provides model validation techniques, such as k-fold cross-validation, time series cross-validation, and grid search, with Rumale interface.

Mongoid Plugin for ClientSideValidations

Formtastic Plugin for ClientSideValidaitons

Several methods in ActiveRecord skip validations, callbacks, or both. In my extremely humble but also extremely correct opinion, it's too easy to accidentally use these. Do Not Want kills those methods dead so you won't cut yourself on them: >> User.new.update_attribute(:foo, 5) DoNotWant::NotSafe: User#update_attribute isn't safe because it skips validation

Adds several handy expectations for testing ActiveRecord model validations, similar to what Shoulda provides.

Parameter Validation and Type Coercion for Rails

Turbolinks Plugin for ClientSideValidaitons

A Rake task investigates the application's models definition, then tells you unique validations that do not have DB indexes.

To ensure Validations that continue to have issues are addressed by developers. This is done by logging the failure. When a specific failure continues to be an issue, a developer can look into the problem.

Store Rails validations as JSON to serve via api and drive complex validation logic.

Adds type validation for classes with ActiveModel::Validations.

Reuse your Rails model validations on the client-side.

Awesome validation and object matching library

Use reflection to spec ActiveModel validations

A collection of Regular Expression validations

Automate the writing of validations, relations in files and specs. Create boilerplate validation in models, specs, migrations. This specs are generated based on rspec, shoulda-matchers and factorygirl

simple_form with client validations

ActiveRecord extension that allows to infer validation rules from database

Provides an ActiveModel validation that checks if an attribute represents a legal BSON::ObjectId .

Add more validation methods for ActiveRecord columns like email, url, and creditcard.