This is a simple machine learning library written in Ruby. It provides implementations of linear regression and multiclass perceptron and visualization and validation methods to verify results. Also included are helper methods to work with training and testing data.

A ruby interface over the DataValidation service.

Reliable contract definition, data validation, and type checking for Ruby.

This gem will use ActiveRecord’s existing validates_format#presence#uniqueness_of method to check whether the email parameter has a valid format, is present and is unique

Advanced ActiveModel email validation with MX lookups, domain blacklisting and disposable email blocking

A simple, localizable EachValidator for email address fields in ActiveRecord 3.0.

Ruby Library for the mailboxlayer API, a web service that email validation & verification, https://mailboxlayer.com/

Add state maps to Rails Enums for validation on transitions.

error_messages_for_helper provides a simple helper to show ActiveRecord validation errors (just like old helper error_messages_for for Rails-2.3.x).

ElasticSearch Queries, gem that allows elastic creation of complex ES queries, and end up in hashes. Validation enabled. Uses eapi gem)

LiveValidation integration with default Rails form helpers and validation methods.

FiletypeValidation is a Ruby gem for validating file content types.

Flags is a framework for Ruby which allows the definition of command-line flags, which are parsed in and can be accessed smartly from within your Ruby code. This framework allows for numerous different flag types, and takes care of the process of type conversion and flag validation (type and val...

Builds forms with a standard template that has labels, hints, and validations

This gem allows model to have state, and based on that create wizard with step by step validations

This is a module for the Ruby language that defines a callback GEDCOM parser. It does not do any validation of a GEDCOM file, but, using application-defined callback hooks, can traverse any well-formed GEDCOM.

Gem for simplify display of validation messages and flash.

Local Apple receipt validation.

Forms with ActiveModel-like validations

ActiveRecord::MySQL::Strict adds validations to ActiveRecord models to make sure they do not trigger errors in MySQL strict mode.