Entasis provides a few useful methods for building a basic class. Handy for models without a database.

Enum machine is a library for defining enums and setting state machines for attributes in ActiveRecord models and plain Ruby classes.

Elasticity provides a higher level abstraction on top of [elasticsearch-ruby](https://github.com/elasticsearch/elasticsearch-ruby) gem

Make your Ruby objects searchable with Elasticsearch.

Provides an easy-to-use ruby interface into the ExactTarget SOAP API, using the Savon client.

Explicit parameters validation and casting for Rails APIs

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Facturación Electrónica de Costa Rica

E-Mail validator for block services like mailinator.com, dropmail.me, etc. during new user registration.

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Provides ActiveModel-like object to read and write.

FlyData Agent

A ruby client for the foscam SDK.

Decouple your forms from your domain models

Client library to interface with Smarthome features of your FritzBox

Elasticsearch integrations for indexing git repositories.

Rails I18n de-facto standard library for ActiveRecord 3 model/data translation.

Provides support for using Paranoia.

Golden Fleece lets you validate, normalize, set up defaults for and provide getters for JSON data in your Ruby data models through easy to use schemas. More opinionated and easier to use than JSON Schema.

Authentication Middleware for Gollum Wiki