Learn how to use Dentaku to evaluate Excel-like formulas in Ruby programs (w. Solomon White)
Issue 8.2 — September 10, 2015

A brief story about why you should play around with problems before trying to solve them.
Issue 8.1 — March 26, 2015

Explore the tradeoffs involved in designing message formats, and the messy boundary between humans and computers.
Issue 7.10 — September 8, 2014

Explore UNIX-style stream processing, binary file formats, the Racc parser generator, and socket programming.
Issue 7.9 — March 31, 2014

Learn three useful practices for maintaining high quality open source projects (w. Eric Hodel)
Issue 7.8 — February 17, 2014

Build Gregory Yob's classic text-based game from scratch, using the provided test suite as a guide.
Issue 7.7 — December 11, 2013

Discover why infrastructure automation matters by exploring real Chef recipes. (w. Mathias Lafeldt)
Issue 7.6 — November 12, 2013

Implement a minimal simulator of the classic 6502 processor using nothing but JRuby.
Issue 7.5 — October 1, 2013

Experience the challenge of overhauling one of Practicing Ruby's oldest features. (w. Jordan Byron)
Issue 7.4 — September 5, 2013

Aggregate and analyze 500+ data points from a SMS-based mood study using R and Ruby. (w. Jia Wu)
Issue 7.3 — August 6, 2013

Build just enough HTTP functionality from scratch to serve up static files. (w. Luke Francl)
Issue 7.2 — July 2, 2013

Practice exploratory programming by modeling forest fires, rabbit populations, and diseases.
Issue 7.1 — June 4, 2013

Save time by building a standalone feature before designing a complete product.
Issue 6.10 — May 7, 2013

Process data and generate reports without writing unmaintainable spaghetti code.
Issue 6.9 — April 23, 2013

Gradually convert a "throwaway" procedural program into a well-defined domain model.
Issue 6.8 — April 10, 2013

Explore the history of a classic design principle and how it relates to Ruby. (w. David A. Black)
Issue 6.7 — March 26, 2013

Tame a complex method interface using keyword arguments and parameter objects.
Issue 6.6 — March 12, 2013

Use stack traces, the Pry console, and tests to hunt bugs with confidence. (w. Carol Nichols)
Issue 6.5 — February 26, 2013

Learn the costs and benefits of the many ways that Ruby lets you reuse code.
Issue 6.4 — February 12, 2013

Solve "Dining Philosophers" using mutex locks, then do it again using actors. (w. Alberto F. Capel)
Issue 6.3 — January 25, 2013

Practice your code reading skills by walking through a small GUI client to the GNU Go game engine.
Issue 6.2 — January 15, 2013

Learn about low-level parser and compiler tools by implementing a JSON parser. (w. Aaron Patterson)
Issue 6.1 — January 1, 2013

Build a text adventure game and a prototype-based object model, at the same time! (w. Avdi Grimm)
Issue 5.10 — December 11, 2012

Explore how simple rules for individuals can yield complex group behavior by simulating an ant colony.
Issue 5.9 — November 27, 2012

See how much even a few dozen lines of code can tell you about a programming language.
Issue 5.8 — November 13, 2012

Learn how to model dependencies, notifications, adjustments, and internal object relationships.
Issue 5.7 — October 28, 2012

Discover the process we use for continuously improving practicingruby.com. (w. Jordan Byron)
Issue 5.6 — October 16, 2012

Implement Ruby's system and backticks methods using the fork/exec pattern. (w. Jesse Storimer)
Issue 5.5 — October 2, 2012

Consider the design tradeoffs between the JSON API and hypermedia API styles. (w. Carol Nichols)
Issue 5.4 — September 18, 2012

Build a Node.js/EventMachine-style event loop in roughly 150 lines of Ruby code. (w. Magnus Holm)
Issue 5.3 — September 4, 2012

See how NASA JPL's take on the Law of Demeter simplifies building robust asynchronous code.
Issue 5.2 — August 19, 2012

Crunch some numbers to see how Olympic medal wins relate to GDP and population. (w. Jia Wu)
Issue 5.1 — August 7, 2012

Search for the boundary lines between organized chaos and wild, unstructured hacking.
Issue 4.12.4 — July 26, 2012

Learn the rules that you need to follow in order to use mock objects as an effective design tool.
Issue 4.12.3 — July 24, 2012

Discover how the differences between refactoring and redesign affect testing strategies.
Issue 4.12.2 — July 19, 2012

Build acceptance tests that reflect application behavior, rather than implementation details.
Issue 4.12.1 — July 18, 2012

Revisit the reasons for Gregory's 90-day self-study on TDD, and see the results.
Issue 4.12 — July 17, 2012

Work through two approaches to object modeling and examine their tradeoffs. (w. Greg Moeck)
Issue 4.11 — July 10, 2012

Consider using "object-oriented mixins" to reduce inheritance-related problems in ActiveRecord.
Issue 4.10 — July 3, 2012

Think through some problems with inheritance-based modeling and then try a few related exercises.
Issue 4.9 — June 19, 2012

Build a basic foundation to serve as the groundwork for implementing an ActiveRecord-style ORM.
Issue 4.8 — June 12, 2012

Develop intention-revealing code that is confident about its responsibilities. (w. Avdi Grimm)
Issue 4.7 — June 5, 2012

Explore some non-traditional persistence mechanisms and their uses. (w. Piotr Szotkowski)
Issue 4.6 — May 21, 2012

Work through a coding puzzle and learn some fun tricks along the way. (w. James Edward Gray II)
Issue 4.5 — May 15, 2012

Tear apart a minimal clone of the Jekyll blog engine in search of helpful Ruby idioms.
Issue 4.4 — May 10, 2012

Think through how to evaluate the impact of test-driven development on your work.
Issue 4.1 — April 10, 2012

Establish a few survival skills for working in hostile programming environments.
Issue 3.10 — March 13, 2012

Learn about modeling non-trivial business logic by implementing Minecraft's crafting table.
Issue 3.9 — February 28, 2012

Discover how Barbara Liskov's concept of "behavioral subtypes" apply to object modeling in Ruby.
Issue 3.8 — February 21, 2012

See how M. Sakkinen's notion of "Disciplined Inheritance" in 1989 still applies to modern Ruby code.
Issue 3.7 — February 15, 2012

Explore some lessons learned the hard way in developing the Newman mail framework.
Issue 3.6 — February 8, 2012

Dig through the Newman mail framework's source code in search of useful patterns and practices.
Issue 3.5 — February 2, 2012

In this issue, we improve the design of the Brainf*ck interpreter that was introduced in Issue 3.3
Issue 3.4 — January 25, 2012

Read the code for a simple Brainf*ck interpreter and think about how it might be improved.
Issue 3.3 — January 17, 2012

Learn how to write code samples that clearly communicate ideas to other programmers.
Issue 3.2 — January 10, 2012

See what ISO/IEC 9126 has to say about software quality, and how its metrics apply to Ruby code.
Issue 3.1 — January 3, 2012

Work through result objects inspired by James Noble's classic "Arguments and Results" paper.
Issue 2.15 — November 30, 2011

Work through argument objects inspired by James Noble's classic "Arguments and Results" paper.
Issue 2.14 — November 23, 2011

Read and write bitmap files using only a few dozen lines of Ruby code.
Issue 2.12 — November 9, 2011

Master classic Ruby DSL design patterns by ripping off well-known libraries and tools.
Issue 2.11 — November 2, 2011

Watch a small game project develop from the brainstorming phase to its first public release.
Issue 2.10 — October 27, 2011

Build a basic clone of the 'cat' utility while learning some Ruby idioms for command line applications.
Issue 2.9 — October 18, 2011

Model the singleton pattern in seven different ways, without discovering an elegant solution.
Issue 2.8 — October 11, 2011

Explore ideas from Mike Burns's "Unobtrusive Ruby" blog post via practical code samples.
Issue 2.7 — October 4, 2011

Build a simple arcade game in 13 tiny steps.
Issue 2.6 — September 27, 2011

Benefit from two lessons about regression testing that were learned the hard way.
Issue 2.5 — September 20, 2011

Learn about Ruby's powerful iteration tools by implementing some of its functionality yourself.
Issue 2.4 — September 13, 2011

Discover why the closure property can sometimes lead to hard-to-spot memory leaks.
Issue 2.3 — September 6, 2011

Work through a few lessons that will help you find a starting point whenever you feel stuck.
Issue 2.2 — August 30, 2011

Explore the strengths and weaknesses of the many code loading mechanisms in Ruby.
Issue 2.1 — August 23, 2011

Examine a use case for each of the classic structural design patterns laid out by the Gang of Four.
Issue 1.26 — February 28, 2011

Examine a use case for each of the classic creational design patterns laid out by the Gang of Four.
Issue 1.25 — February 22, 2011

Work through code samples inspired by Jim Weirich's "Building Blocks of Modularity" presentation.
Issue 1.24 — February 11, 2011

Work through code samples inspired by Sandi Metz's "SOLID Object-oriented Design" presentation.
Issue 1.23 — February 5, 2011

See an example of how the practice methods outlined in Issue 1.21 can be applied to a real project.
Issue 1.22 — January 28, 2011

Discover a new way to practice your coding skills by asking yourself the right questions.
Issue 1.21 — January 26, 2011

Explore a few good uses of mock objects from a non-mockist's perspective.
Issue 1.20 — January 22, 2011

Consider how the ideas from Martin Fowler's "Mocks aren't Stubs" can be applied to Ruby.
Issue 1.19 — January 19, 2011

Take a look at some dark corners of the traditional testing dogma.
Issue 1.18 — January 14, 2011

Find out which Ruby hackers consistently write great content worth reading.
Issue 1.17 — January 7, 2011

Find out which Ruby hackers consistently write great code worth reading.
Issue 1.16 — January 3, 2011

Examine real uses of Ruby's duck-typing capabilities in various open source projects and Ruby itself.
Issue 1.15 — December 31, 2010

Investigate the three main ways of doing type checking in Ruby, then work on some related exercises.
Issue 1.14 — December 28, 2010

Tear apart an obfuscated Ruby program from Leah Neukirchen to learn some neat tricks.
Issue 1.13 — December 23, 2010

Build a tiny prototype of a tetris game on the command line.
Issue 1.12 — December 21, 2010

Explore the use of mixins for customizing individual objects.
Issue 1.11 — December 16, 2010

Learn the subtle differences between "extend self", "def self.method", and "module_function".
Issue 1.10.a — December 15, 2010

See how modules can be used as namespaced function bags, and as singleton objects.
Issue 1.10 — December 14, 2010

Use mixins as an alternative to multiple inheritance to augment class definitions.
Issue 1.9 — December 10, 2010

Use modules as namespaces for your libraries and applications.
Issue 1.8 — December 8, 2010

Read through a cleaned up version of the ugly "Tic Tac Toe" game created in Issue 1.5
Issue 1.7 — December 3, 2010

Build an ugly tic-tac-toe game by writing the entire implementation as a single procedural script.
Issue 1.6 — December 1, 2010

Understand why testing private methods can be a code smell.
Issue 1.5 — November 25, 2010

Build dynamic Ruby-based configuration objects.
Issue 1.4 — November 18, 2010

Learn what not to do when configuring applications, then explore a simple YAML-based configuration.
Issue 1.3 — November 16, 2010

Use your knowledge of Ruby's lookup path to determine where to add methods in a program.
Issue 1.2 — November 11, 2010

Discover the complicated, multi-step dance that is the Ruby method lookup path.
Issue 1.1 — November 9, 2010