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

Formtastic Plugin for ClientSideValidaitons

Mongoid Plugin for ClientSideValidations

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) DoNotWa...

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

Parameter Validation and Type Coercion for Rails

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

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

Adds type validation for classes with ActiveModel::Validations.

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.

Turbolinks Plugin for ClientSideValidaitons

It will handle validations inline

Extra matchers to test model validation

Automatically pull validations out of your database and apply them to your models

An easy to use Ruby built-in type validations library.

Validation of params for Sinatra

Another validation library

Package containing validations: .

RailsAjaxFormhandler is a lightweight Javascript-plugin which submits your form automatically and displays server responded validation-errors by adding styles and error-messages to the invalid input fields.

Ember Plugin for ClientSideValidaitons