Umwelt is a domain architecture development(knowledge management) tool, for handy prototyping domain specification with code structure.

Generate random unambiguous strings (no ilo06b2z chars)

UnasukeCop is a RuboCop configration gem that optimisation to unasuke.

A gem that lets you call into the Camelot Unchained API. You can see the API docs at https://api.camelotunchained.com

Provide ISO 3166 codes and english name for countries and their political divisions

Uncle Kryon server (& hacker) for the Uncle Kryon mobile apps.

A mutex that uses Redis that is also not complicated.

API Client for the Weather Underground

undo-manager makes it easy to add undo/redo functionality to a Ruby (on Rails) app.

Provides a Result class for more elegant, exception-free error handling. Especially useful for processing input that could be invalid for many different reasons.

Removes, replaces, transforms, or detects non-alphanumeric Unicode characters in a string

Generates unicode country flags from country code

A Ruby port of the unicode character data

Convert non-English accented characters to their HTML-friendly format.

Graceful handling of requests which are reaching the timeout limit to avoid SIGKILL

Unicorn Standby is on standby until it accepts the request.

An unofficial unionpay gem

apimatic_calculator

A comprehensive Ruby gem that handles document processing, text extraction, and AI-powered analysis for PDF, Word, Excel, PowerPoint, images, archives, and more with a unified API. Includes agentic AI features for document analysis, summarization, and intelligent extraction.

gem install universe-testing