Instead of using the build-in asset pipeline of Rails, use faucet-pipeline. This gem enables the required integration with Rails.

faultline exception and error notifier for Ruby

faultline exception and error notifier for Rack application

fauxpaas-client

favicon_gem is a Ruby library to find a website's favicon, ported from Python's favicon library

favicon_get is a Ruby library to find a website's favicon, ported from Python's favicon library

Fiction Book 2 parser/generator library

fbsimctl extension provides convenient metaclass to execute FBSimulatorControl shell commands.

Simple but fast.

A Ruby wrapper for Fcoin API

Ruby Function Developer Kit for Fn Project.

FeatureMap helps identify and manage features within large Ruby and Rails applications. This gem works best in large, usually monolithic code bases for applications that incorporate a wide range of features with various dependencies.

This gem introduces the concept of "features" and "settings" to your Rails app. It provides an easy way to define such features and settings with default values right in your code and will persist them in the database.

Change all file extensions in folder.

Federal Offense intercepts outbound emails in Rails and allows you to preview them in a user-configurable mounted location

Interface for FedEx Label Services API.

Interface for FedEx Location Services API.

feger.io api gem

A feed posts aggregator for rss and facebook pages

Atypon RSS format parser for Feedjira