stackprof is a fast sampling profiler for Ruby code, with cpu, wallclock and object allocation samplers.

Haml is a layer on top of HTML or XML that is designed to express the structure of documents using indentation rather than closing tags. It was originally envisioned as a plugin for Ruby on Rails, but it can function as a stand-alone templating engine.

Concurrent Ruby includes concurrency tools such as agents, futures, promises, thread pools, actors, supervisors, and more. It is inspired by Erlang, Clojure, Go, JavaScript, actors, and classic concurrency patterns.

CI::Reporter is an add-on to Ruby testing frameworks that allows you to generate XML reports of your test runs. The resulting files can be read by a continuous integration system that understands Ant's JUnit report format.

Zeitwerk implements constant autoloading with Ruby semantics. Each gem and application may have their own independent autoloader, with its own configuration, inflector, and logger. Supports autoloading, reloading, and eager loading.

This gem generates a treemap showing the complexity of Ruby code on which it is run. It uses Saikuro under the covers to analyze Ruby code complexity.

Rerun is a tool to launch programs, then monitor the file system, and restart the program when any of the monitored files change. It's written in Ruby, but can be used for all programs.

This package provides a plugin for the RuboCop code style enforcing & linting tool for factory_bot files.

Net::SSH is a pure-Ruby implementation of the SSH2 client protocol. It allows you to write programs that invoke and interact with processes on remote servers, via SSH2.

This package allows you to test FTP implementations in ruby. It is a minimal single-client FTP server that can be bound to any arbitrary port on localhost.

This package provides a Partial native implementation of the liquid ruby gem in C that makes it operate about three times faster.

Rubygems-task provides Rake tasks for managing and releasing Ruby Gems.

The httpclient ruby library provides functionality related to HTTP. Compared to the net/http library, httpclient also provides Cookie, multithreading and authentication (digest, NTLM) support.

Also provided is a httpclient command, which can perform HTTP requests either using arguments or with an interactive prompt.

Multihashes provides a simple, low-level multihash implementation for Ruby. A multihash is a digest with an embedded hash function code

This gem provides beautiful console logging for Ruby applications. It implements fast, buffered log output and has the following features:

• Thread safe global logger with per-fiber context

• Carry along context with nested loggers

• Enable/disable log levels per class

• Detailed logging of exceptions

• Beautiful logging to the terminal or structured logging using JSON.

This package provides a Language Server Protocol (LSP) development kit for Ruby.

Warden is a Rack-based middleware that provides a mechanism for authentication in Ruby web applications.

This package provides an alternative implementation of the Ruby GetText library that is approximately 12x faster yet thread safe.

HTMLProofer is a set of tests to validate your HTML output. These tests check if your image references are legitimate, if they have alt tags, if your internal links are working, and so on. It's intended to be an all-in-one checker for your output.

This library provides a simple API for XML processing in Ruby.

The test-queue module is a parallel test runner, built using a centralized queue to ensure optimal distribution of tests between workers. It is specifically optimized for Continuous Integration (CI) environments: build statistics from each run are stored locally and used to sort the queue at the beginning of the next run.

LazyObject is an object wrapper that forwards all calls to the reference object. This object is not created until the first method dispatch.

Open4 is a Ruby library to run child processes and manage their input and output.

HTTP::Cookie is a Ruby library to handle HTTP Cookies based on RFC 6265. It has been designed with security, standards compliance and compatibility in mind, to behave just the same as today's major web browsers. It has built-in support for the legacy cookies.txt and cookies.sqlite formats of Mozilla Firefox.