Provides subset validation for serialized arrays or sets in Active Record

UPS address validation gem

Calls and parses various maps APIs for accurate address validation and geocoding

Versions validations and comparisons!!!

Get validation error from database constraint.

Cave Forms encapsulate validation logic into an object with that single responsibility

Imports delimited text files to Active Record or Datamapper, with validations.

Clean Language Validation

Providing special validation error building for has_many collection in Rails.

Simple way to do validations more clear :)

A runtime validation configuration DSL

Configurator for Ruby Applications with some validation and sugars.

Adds a test that validates all your Rails fixtures.

BagIt package generation and validation

Format and validation a URL in active record

A simple js form validation

ENV var to Config object translation with validations.

Collection of validations and complex assertions

Plinko helps you create validators that collect all validation errors instead of breaking on the first failure.

Create K-fold splits from data files and assist in training and testing (useful for cross-validation in supervised machine learning)