Archive::Tar::Minitar is a pure-Ruby library and command-line utility that provides the ability to deal with POSIX tar archive files.

m stands for metal, a better test/unit and minitest test runner that can run tests by line number.

cliver provides a way to detect missing command-line dependencies, including versions.

The FileUtils Ruby library includes Several file utility methods for copying, moving, removing, etc.

Delayed_job (or DJ) encapsulates the common pattern of asynchronously executing longer tasks in the background. It is a direct extraction from Shopify where the job table is responsible for a multitude of core tasks.

Ruby-Locale is the pure ruby library which provides basic APIs for localization.

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.

Mustache is a framework-agnostic way to render logic-free views. Think of Mustache as a replacement for your views. Instead of views consisting of ERB or HAML with random helpers and arbitrary logic, your views are broken into two parts: a Ruby class and an HTML template.

This pure ruby library provides spawn() which is almost perfectly compatible with ruby 1.9's.

Fuubar is an RSpec formatter that uses a progress bar instead of a string of letters and dots as feedback. It also stops on the first test failure.

Packnga is a library to translate to many languages using YARD.

ProgressBar is a simple library for displaying progress bars. The maximum value is configurable, and additional information can be displayed like the percentage completion, estimated time remaining, elapsed time and rate.

rb-inotify is a simple wrapper over the inotify Linux kernel subsystem for monitoring changes to files and directories.

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.

Oj is a JSON parser and generator for Ruby, where the encoding and decoding of JSON is implemented as a C extension to Ruby.

Byebug is a Ruby 2 debugger implemented using the Ruby 2 TracePoint C API for execution control and the Debug Inspector C API for call stack navigation. The core component provides support that front-ends can build on. It provides breakpoint handling and bindings for stack frames among other things and it comes with a command line interface.

The x25519 gem is an efficient public key cryptography library for Ruby providing key exchange/agreement via the X25519 (as known as Curve25519) Elliptic Curve Diffie-Hellman function as described in RFC 7748.

This is an experimental gem that extracts low-level PDF functionality from Prawn.

This package provides a JSON implementation written in pure Ruby.

Ruby i18n is an internationalization and localization solution for Ruby programs. It features translation and localization, interpolation of values to translations, pluralization, customizable transliteration to ASCII, flexible defaults, bulk lookup, lambdas as translation data, custom key/scope separator, custom exception handlers, and an extensible architecture with a swappable backend.

HashDiff is a Ruby library to compute the smallest difference between two hashes.

pkg-config can be used in your extconf.rb to properly detect need libraries for compiling Ruby native extensions.

Bacon is a small RSpec clone providing all essential features.

This package provides a Ruby implementation of RFC5869: HKDF. The goal of HKDF is to take some source key material and generate suitable cryptographic keys from it.