Curated List
Admin Panels
Libraries for administrative interfaces.
active_admin The administration framework for Ruby on Rails applications
rails_admin A Rails engine that provides an easy-to-use interface for managing your data
administrate A framework for creating flexible, powerful admin dashboards in Rails.
Anti-spam
Libraries for fighting spam.
RubySpamAssassin Kills Spam Dead. Perhaps before it's sent!
Asset Management
Tools for managing, compressing and minifying website assets.
sprockets Rack-based asset packaging system
rails-assets is the frictionless proxy between Bundler and Bower
Audio
seal A C library (with Ruby binding) for 3D audio rendering
Auditing
Tools for logging changes to ActiveRecord models
Audited - Audited (formerly acts_as_audited) is an ORM extension that logs all changes to your Rails models.
Authentication and OAuth
Libraries for implementing authentications schemes.
Devise - Devise is a flexible authentication solution for Rails based on Warden
Omniauth - OmniAuth is a flexible authentication system utilizing Rack middleware
Warden - General Rack Authentication Framework
AuthLogic - A simple ruby authentication solution
Sorcery - Magical authentication for Rails 3 & 4
CanCanCan Authorization gem for Rails (continued version of CanCan from ryanb)
pundit - Minimal authorization using object oriented design.
authority - ORM neutral authorization.
doorkeeper An OAuth 2 provider for Rails
tiddle - Devise strategy for token authentication in API-only Ruby on Rails applications
Build Tools
Compile software from source code.
teapot A decentralised build tool for managing complex cross-platform projects
Caching
Libraries for caching data.
rack-cache HTTP Caching for Ruby Web Apps
Dalli - a high performance pure Ruby client for accessing memcached servers.
Cloud Services
fog The Ruby cloud services library
aws-sdk-ruby The official AWS SDK for Ruby
CMS
Content management systems
Refinery CMS An extendable Ruby on Rails CMS that supports Rails 3.2 and 4.2
Comfortable Mexican Sofa A powerful Rails 4/5 CMS Engine
Browser Humane Content Management for Rails
Locomotive a brand new CMS system with super sexy UI and cool features
Radiant A no-fluff, open source content management system
Nesta A lightweight CMS, implemented in Sinatra
alchemy_cms the most powerful, user friendly and flexible Rails CMS
weby Newbie CMS in Ruby on Rails
Code Analysis and Linter
Libraries and tools for analyzing, parsing and manipulation codebases.
Rubocop - A Ruby static code analyzer, based on the community Ruby style guide.
ruby-lint - ruby-lint is a static code analysis tool for Ruby
brakeman - Static analysis tool which checks Ruby on Rails applications for security vulnerabilities
reek - Code smell detector for Ruby
Command-line Tools
Libraries for building command-line application.
Commander - The complete solution for Ruby command-line executables
Thor - Thor is a toolkit for building powerful command-line interfaces
Configuration
Libraries for storing configuration options.
CSS and Styling
sass A CSS preproccessor
sass-rails Rails stylesheet engine for Sass
less-rails The dynamic stylesheet language for the Rails
compass A a Stylesheet Authoring Environment
bootstrap-sass Official Sass port of Bootstrap
foundation-rails Foundation for Rails
bootswatch-rails Bootswatches converted to SCSS ready to use in Rails
bourbon A lightweight mixin library for Sass
Data Validation
Libraries for validating data. Used for forms in many cases.
kangal - Extended validation gem for email, subdomain, credit card, tax number etc
bin_checker - BIN validator for Turkish Banks
Data Visualization
Libraries for visualizing data.
prosperity The easiest way to graph data from your Rails models
Database Drivers
Libraries for connecting and operating databases.
Relational Databases
ruby-pg Ruby interface to the PostgreSQL >= 8.4
mysql2 A modern, simple and very fast Mysql library for Ruby
sqlite3-ruby Ruby bindings for the SQLite3 embedded database
NoSQL Databases
Date and Time
Libraries for working with dates and times.
Debugging Tools
Libraries for debugging and developing.
DevOps Tools
Software and libraries for DevOps.
Puppet - Server automation framework and application
Chef - A systems integration framework, built to bring the benefits of configuration management to your entire infrastructure.
Vagrant - Vagrant is a tool for building and distributing development environments.
Capistrano - Remote multi-server automation tool
Mina Really fast deployer and server automation tool
Nanobox - A micro-PaaS (μPaaS) for creating consistent, isolated, Ruby environments deployable anywhere https://nanobox.io.
Distribution
Libraries to create packaged executables for release distribution.
fpm Building packages for multiple platforms (deb, rpm, etc) with great ease and sanity.
Documentation
Libraries for generating project documentation.
Dictum - A tool that let's you create automatic documentation of your Rails API endpoints through your tests.
rdoc HTML and online documentation for Ruby projects
yard A Ruby Documentation tool
Downloader
Libraries for downloading.
GitHub Starred Repos Downloader - gsrd downloads your public starred repos. Just in case you want to keep a backup of them from time to time.
E-Commerce & Online Paying
Active Merchant - A simple payment abstraction library extracted from Shopify.
Spree - A complete open source e-commerce solution for Ruby on Rails.
PayPal Merchant SDK - Provides Ruby APIs for processing payments, recurring payments, subscriptions and transactions using PayPal's Merchant APIs.
E-Mail
Libraries for sending and parsing email.
Environment Management
Libraries for Ruby version and environment management.
chruby - Changes the current Ruby
chgems - Chroot for RubyGems
rvm - Ruby Version Manager
rbenv - Groom your app’s Ruby environment
ruby-install - Installs Ruby, JRuby, Rubinius, MagLev or MRuby
ruby-build - Compile and install Ruby
Nanobox - A tool for creating isolated Ruby environments for consistency across teams and application stages (dev, staging, production, etc.) https://nanobox.io.
Error Handling
Libraries for exception and error handling.
Exception Notification - A set of notifiers for sending notifications when errors occur in a Rack/Rails application
Errbit - The open source, self-hosted error catcher
Airbrake - The official Airbrake library for Ruby on Rails (and other Rack based frameworks)
Better Errors - Better error page for Rack apps
File Uploading
Libraries for handling file uploads.
paperclip Easy file attachment management for ActiveRecord
dragonfly On-the-fly processing - suitable for image uploading in Rails, Sinatra and much more
carrierwave Classier solution for file uploads for Rails, Sinatra and other Ruby web frameworks
attache - Yet another approach to file upload https://attache-demo.herokuapp.com
Feature flipping
Libraries for flipping features
helioth Manage feature flipping and rollout
flipper feature flipping for ANYTHING
flip Flip lets you declare and manage feature flags, backed by cookies (private testing) and database (site-wide)
rollout Feature flippers.
Foreign Function Interface
Libraries for providing foreign function interface.
Forms
Libraries for working with forms.
simple_form Forms made easy for Rails
formtastic A Rails form builder plugin with semantically rich and accessible markup
Game Development
Awesome game development libraries.
Gosu - A 2D game development library for the Ruby and C++ programming languages
Geolocation
Libraries for geocoding addresses and working with latitudes and longitudes.
geocoder Complete Ruby geocoding solution
Geokit - Geokit gem provides geocoding and distance/heading calculations.
Git Tools
Libraries for working with Git VCS
katip - Change logger for Git initialized projects
GUI
Libraries for working with graphical user interface applications.
High Performance
Libraries for making Ruby faster.
EventMachine - EventMachine: fast, simple event-processing library for Ruby programs
Celluloid - Actor-based concurrent object framework for Ruby. It has its own awesomeness.
HTML/XML/CSS Manipulation
Libraries for working with HTML, XML & CSS.
loofah A general library for manipulating and transforming HTML/XML documents and fragments
HTTP
Libraries for working with HTTP.
httparty Makes http fun again!
faraday Simple, but flexible HTTP client library, with support for multiple backends.
http A simple Ruby DSL for making HTTP requests
excon Usable, fast, simple HTTP(S) 1.1 for Ruby
nestful Simple Ruby HTTP/REST client with a sane API
Imagery
Libraries for manipulating images.
rmagick An interface to the ImageMagick and GraphicsMagick image processing libraries
minimagick Minified version of rmagick
chunky_png Read/write access to PNG images in pure Ruby
image_optim Optimize images using multiple utilities
magickly image manipulation as a (plugin-able) service
Internationalization
Libraries for woking with i18n.
i18n - Basic internationalization(i18n) library for Ruby
globalize Rails I18n de-facto standard library for ActiveRecord model/data translation
i18n-tasks Manage translations in ruby applications with the awesome power of static analysis
Logging
Libraries for generating and working with log files.
Logstash Logstash is a tool for managing events and logs.
Machine Learning
Libraries for Machine Learning.
PredictionIO Ruby SDK - The PredictionIO Ruby SDK provides a convenient API to quickly record your users' behavior and retrieve personalized predictions for them
MapReduce
Frameworks and libraries for MapReduce.
Multi-tenancy
Libraries for managing multi-tenant apps.
Apartment - Database multi-tenancy for Rack (and Rails) applications
Natural Language Processing
Libraries for working with human languages.
Treat - Treat is a toolkit for natural language processing and computational linguistics in Ruby
Networking
Libraries for network programming.
ORM
Libraries that implement Object-Relational Mapping or data mapping techniques.
Relational Databases
ActiveRecord - Databases on Rails. Build a persistent domain model by mapping database tables to Ruby classes
DataMapper - DataMapper is an Object Relational Mapper written in Ruby. The goal is to create an ORM which is fast, thread-safe and feature rich.
Sequel - The Database Toolkit for Ruby
Package Management
Libraries for package and dependency management.
RubyGems - RubyGems is a package manager for the Ruby programming language that provides a standard format for distributing Ruby programs and libraries
Bundler - Bundler provides a consistent environment for Ruby projects by tracking and installing the exact gems and versions that are needed
Homebrew - Homebrew installs the stuff you need that Apple didn’t
Homebrew Cask - Cask provides a friendly homebrew-style CLI workflow for the administration of Mac applications distributed as binaries
Pagination
kaminari A Scope & Engine based, clean, powerful, customizable and sophisticated paginator
will_paginate Pagination library for Rails 3, Sinatra, Merb, DataMapper, and more
order_query Keyset pagination to find the next or previous record(s) relative to the current one efficiently, e.g. for infinite scroll.
PDF Processing
DocRaptor Wrapper library for DocRaptor's Ruby-based HTML-to-PDF API
wicked_pdf PDF generator (from HTML) plugin for Ruby on Rails
pdfkit HTML+CSS to PDF using wkhtmltopdf
prawn Fast, Nimble PDF Writer for Ruby
InvoicePrinter - Super simple PDF invoicing in Ruby (built on top of Prawn).
Presentation Tools
Processes and Threads
Libraries for woking with processes or threads
Parallel - Ruby parallel processing made simple and fast
Profiling
bullet - help to kill N+1 queries and unused eager loading
Push Notification
Rpush - The push notification service for Ruby.
apn_sender - Background worker to send Apple Push Notifications over a persistent TCP socket.
Houston - A simple gem for sending Apple Push Notifications.
Queue
Libraries for working with event and task queues.
Resque A Redis-backed Ruby library for creating background jobs, placing them on multiple queues.
Delayed::Job — Database backed asynchronous priority queue.
Qu A Ruby library for queuing and processing background jobs.
Sidekiq Simple, efficient background processing for Ruby
RESTful API
Libraries for developing RESTful APIs.
Grape - An opinionated micro-framework for creating REST-like APIs in Ruby.
Rails::API - Rails for API only applications
jbuilder - Create JSON structures via a Builder-style DSL
rabl - General Ruby templating with json, bson, xml, plist and msgpack support
active_model_serializers - ActiveModel::Serializer implementation and Rails hooks
oat - Adapters-based API serializers with Hypermedia support for Ruby apps (HAL, Siren, JSONAPI).
Spreadsheets
Libraries for manipulating Excel, Google Spreadsheets, Numbers, OpenOffice and LibreOffice files
spreadsheet - The Spreadsheet Library is designed to read and write Spreadsheet Documents.
axlsx - Axlsx excels at helping you generate beautiful Office Open XML Spreadsheet documents.
axlsx_rails - Axlsx_Rails provides an Axlsx renderer so you can move all your spreadsheet code from your controller into view files.
roo - Roo implements read access for all spreadsheet types and read/write access for Google spreadsheets.
google-spreadsheet-ruby - This is a library to read/write Google Spreadsheet.
rubyXL - rubyXL is a gem which allows the parsing, creation, and manipulation of Microsoft Excel (.xlsx/.xlsm) Documents
Odf-report - Generates ODF files, given a template (.odt) and data, replacing tags
simple_xlsx_writer - Just as the name says, simple writter for Office 2007+ Excel files
remote_table - Open local or remote XLSX, XLS, ODS, CSV (comma separated), TSV (tab separated), other delimited, fixed-width files, and Google Docs.
acts_as_xlsx - acts_as_xlsx lets you turn any ActiveRecord::Base inheriting class into an excel spreadsheet.
activeadmin-axlsx - This gem uses axlsx to provide excel/xlsx downloads for resources in Active Admin.
to_spreadsheet - Render XLSX from Rails using existing views
write_xlsx - write_xlsx is a gem to create a new file in the Excel 2007+ XLSX format.
excel_rails - Allows you to program spreadsheets using .rxls views
sheets - Work with spreadsheets easily in a native ruby format.
workbook - Workbook contains workbooks, as in a table, contains rows, contains cells, reads/writes excel, ods and csv and tab separated files...
Spreadsheet report - Simple tool for running queries against ActiveRecord and putting them into a Google Spreadsheet.
oxcelix - A fast Excel 2007/2010 (.xlsx) file parser that returns a collection of Matrix objects
wrap_excel - WrapExcel is to wrap the win32ole, and easy to use Excel operations with ruby. Detailed description please see the README.
write_xlsx_rails - xlsx renderer for Rails base on write_xlsx gem
Fastsheet - Fast spreadsheet reader using Rust native extensions.
Scheduling
whenever Cron jobs in Ruby
resque-scheduler A light-weight job scheduling system built on top of resque
rufus-scheduler Scheduler for Ruby
Clockwork Clockwork is a cron replacement. It runs as a lightweight, long-running Ruby process which sits alongside your web processes (Mongrel/Thin) and your worker processes (DJ/Resque/Minion/Stalker) to schedule recurring work at particular times or dates.
Science and Data Analysis
Libraries for scientific computing and data analyzing.
Search
Libraries and software for indexing and performing search queries on data.
Thinking Sphinx - Sphinx plugin for ActiveRecord/Rails
elasticsearch-ruby - Ruby integrations for Elasticsearch
Searchkick - Intelligent search made easy
Algoliasearch Rails - AlgoliaSearch integration to your favorite ORM
PgSearch - PostgreSQL's full text search
Rroonga - The Ruby bindings of Groonga
Sunspot - Solr-powered search for Ruby objects
Site Monitoring
Libs for analytics, monitoring
rack-google-analytics Simple Rack middleware for implementing google analytics tracking
DataDog A monitoring service for IT, operations and development teams
Instrumental High-scale, non-blocking agent for Instrumental application monitoring
Keen IO Build analytics features directly into your Ruby apps
Static Page Generation
jekyll A blog-aware, static site generator in Ruby
Starter Apps
App templates for creating apps quickly
suspenders A Rails template with our standard defaults, ready to deploy to Heroku
ruby2-rails4-bootstrap-heroku A starter application based on Ruby 2, Rails 4 and Bootstrap for Sass, deployable on Heroku
rails-bootstrap Rails 4.1 starter app with the Bootstrap front-end framework
rails4-starterkit Rails 4.1 starter app with production ready performance, security, and authentication
cybele - Rails 4.x template with responder, simple form, haml, exception notification, etc ...
Text Processing
Libraries for parsing and manipulating texts.
General
Specific Formats
Parser
Yomu - Read text and metadata from files and documents (.doc, .docx, .pages, .odt, .rtf, .pdf)
Tagging
Libraries for tagging items.
acts-as-taggable-on - A tagging plugin for Rails applications that allows for custom tagging along dynamic contexts.
Template Engine
Libraries and tools for templating and lexing.
Slim A templating lang that reduce the syntax to the essential parts without becoming cryptic.
slim-rails Rails port of Slim lang
Haml HTML Abstraction Markup Language - A Markup Haiku
haml-rails Rails port of Haml lang
Testing
Libraries for testing codebases and generating test data.
Testing Frameworks
RSpec - BDD for Ruby
MiniTest - minitest provides a complete suite of testing facilities supporting TDD, BDD, mocking, and benchmarking
[Cucumber]
Cucumber Github - Cucumber is a tool that executes plain-text functional descriptions as automated tests
Cucumber Site - Behaviour Driven Development with elegacy and joy
Spinach - Spinach is a high-level BDD framework that leverages the expressive Gherkin language (used by Cucumber) to help you define executable specifications of your application or library's acceptance criteria.
shoulda-matchers - Collection of testing matchers extracted from Shoulda
capybara - Acceptance test framework for web applications
Mock
RSpec-mocks - RSpec's 'test double' framework, with support for stubbing and mocking
Mocha - Mocking and stubbing library with JMock/SchMock syntax, which allows mocking and stubbing of methods on real (non-mock) classes.
FlexMock - Flexible mocking for Ruby testing
Code Coverage
simplecov Code coverage for Ruby 1.9+ with a powerful configuration library and automatic merging of coverage
Load Testing
Error Handler
Third-party APIs
Libraries for accessing third party APIs.
koala A lightweight, flexible library for Facebook
fb_graph A full-stack Facebook Graph API wrapper
twitter A Ruby interface to the Twitter API
tweetstream A simple library for consuming Twitter's Streaming API
gitlab Ruby wrapper and CLI for the GitLab API
octokit.rb Ruby toolkit for the GitHub API
instagram The official gem for the Instagram API
linkedin Ruby wrapper for the LinkedIn API
twilio-ruby A Ruby gem for communicating with the Twilio API and generating TwiML
viewpoint-spws A Microsoft Sharepoint Web Services library for Ruby.
youtube_it An object-oriented Ruby wrapper for the YouTube GData API
flickraw Flickraw is a library to access flickr api
f00px Official 500px api ruby gem
rspotify Ruby wrapper for the Spotify Web API
URL Manipulation
Libraries for parsing URLs.
Video
Libraries for manipulating video and GIFs.
streamio-ffmpeg Simple yet powerful ruby FFmpeg wrapper for reading metadata and transcoding movies
Web Content Extracting
Libraries for extracting web contents.
Web Crawling
Libraries for scraping websites.
upton A batteries-included framework for easy web-scraping
Web Frameworks
Web development frameworks.
Ruby On Rails - Ruby on Rails is a full-stack web framework optimized for programmer happiness and sustainable productivity
Sinatra - Sinatra is a DSL for quickly creating web applications in Ruby with minimal effort.
Padrino - The Godfather of Sinatra provides a full-stack agnostic framework on top of Sinatra
Cramp - Cramp is a fully asynchronous real-time web application framework in Ruby
Lotus - A newborn complete Ruby web framework that is simple, fast and lightweight.
Cuba - Cuba is a microframework for web development originally inspired by Rum, a tiny but powerful mapper for Rack applications.
Pakyow - Pakyow is an open-source framework for the modern web. Build working software faster with a development process that remains friendly to both designers and developers. It's built for getting along.
Hyperloop - A complete Isomorphic Ruby Framework using React, Opal and Rails
Web Servers
App server interface
puma A simple, fast, threaded, and highly concurrent HTTP 1.1 server for Ruby/Rack applications.
thin A thin and fast web server
trinidad Run Rails or Rack applications within an embedded Apache Tomcat container.
unicorn An HTTP server for Rack applications designed to only serve fast clients.
passenger A modern web server and application server for Ruby, Python, and Node.js.
pow Pow treats files and directories as ruby objects giving you more power and flexibility.
goliath is a non-blocking Ruby web server framework.
WebSocket
Libraries for woking with WebSocket.
Faye - Simple pub/sub messaging for the web
websocket-rails - Plug and play websocket support for ruby on rails.
Miscellaneous
Useful libraries or tools that don't fit in the categories above.
packetfu A mid-level packet manipulation library for Ruby.
chatterbot A straightforward ruby-based Twitter Bot Framework, using OAuth to authenticate
sneakers A fast background processing framework for Ruby and RabbitMQ
ransack Object-based searching.
cinch The IRC Bot Building Framework
pry An IRB alternative and runtime developer console
jazz_hands Pry-based enhancements for the default Rails 3 and 4 consoles
awesome_print A Ruby library that pretty prints Ruby objects in full color exposing their internal structure with proper indentation.
friendly_id Slugging and permalink plugins for ActiveRecord
backup An elegant DSL in Ruby for performing backups on UNIX-like systems
kss Documenting CSS and generating styleguides
AASM - A library for adding finite state machines to Ruby classes
JsonCompare - Returns the difference between two JSON files
blankable - Adds blank slates to index view in Rails
tcmb_currency - T.C.M.B. currencies for Money Gem
enumerize - Enumerated attributes with I18n and ActiveRecord/Mongoid support
lol_dba - lol_dba is a small package of rake tasks that scan your application models and displays a list of columns that probably should be indexed.
annotate-models - Annotate ActiveRecord models
fast_attributes - FastAttributes adds attributes with their types to the class
Github Changelog Generator — automatically generate change log from your tags, issues, labels and pull requests on GitHub.
Letter Opener — Preview email in the default browser instead of sending it.
Auto HTML — Transforming URLs to appropriate resource (image, link, YouTube, Vimeo video,...).
OctoLinker - Navigate through projects on GitHub.com efficiently with the OctoLinker browser extension.
Resources
Where to discover things (libraries, news e.g) about Ruby.
RubyDaily - Community driven news
Ruby Weekly - A free, once–weekly e-mail round-up of Ruby news and articles.
Ruby5 - The latest news in the Ruby and Rails community
RubyFlow - Ruby Programming Community Link Blog
GemBundle - A place to discover new Ruby Gems
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