The email equivalent of has_secure_password for ActiveRecord.

A Ruby gem that provides OAuth 2.0 authentication and API client functionality for TradeStation's trading platform. Supports both production and sandbox environments.

Oauth authentication for bombbomb.

Ruby/NTLM HTTP provides NTLM authentication over http.

CLI tool to obtain certificates via ACME and update the matching TLSA records. The primary authentication method is http-01 via webroot for now, but dns-01 is supported too.

Action Interceptor provides methods to store return url's across multiple requests. Useful during authentication, registration, signing terms of use, etc.

HTTP dialog for the Acenda API with the oAuth2 authentication.

Non-password Authentication with Facebook Account Kit for Rails app

A gem to safely provide external application resources with a coherent and configurable API to a host application's authentication procedures.

Simple Instagram feed by hashtag, returns a JSON, no API authentication needed.

A Ruby client for the Jumingo API, including authentication, errors, and endpoint helpers.

OAuth 2.0 authentication and API calls for Rdio Web Service API.

As fate would have it, I found other authentication solutions unable to suit my needs. So I rolled my own, totally supporting Rails 2 AND 3.

A ruby implementation of RFC4493, RFC4494, and RFC4615. CMAC is a message authentication code (MAC) built using AES-128.

Static authentication && authorization in rails.

rack middleware providing session based authentication

BotDelive is a Push Notification and 2-factor authentication API service that works over the chat bots (Telegram and Messenger).

A CLI tool and its associated Ruby library that help you locate and reconnect to a running SSH agent. Useful in automation scenarios where multiple processes must repeatedly open SSH connections leveraging a one-time authentication pass

A ruby gem for the SQRL authentication system described by Steve Gibson of GRC.com

JWT authentication and authorization midleware with multi-tenant suport,\ company validation, and subdomain isolation.