--- title: "This week's Ruby news, issue 234" publication: "Ruby Weekly" issue: 234 published_at: "2015-02-19" canonical_url: "https://rubyweekly.com/issues/234" --- This week's Ruby news, issue 234 This week's Ruby and Rails news[Read this e-mail on the Web](http://rubyweekly.com/issues/234) Ruby WeeklyIssue 234 — February 19, 2015 Aaron Patterson[Predicting Test Failures](http://tenderlovemaking.com/2015/02/13/predicting-test-failues.html)One way to save time when running tests is to, well, not run some of them. Aaron Patterson of the Ruby and Rails core teams looks at what’s involved in building a ‘regression test selector’ to only test code that has actually changed. Ben Lewis[Getting Started With Ruby Processing](https://blog.engineyard.com/2015/getting-started-with-ruby-processing)Ruby Processing provides a mechanism to use the Processing visual arts programming environment from Ruby. This is an introduction to using it to build your own visualizations. Pat Shaughnessy[Mark Methods Private When You Don’t Test Them](http://patshaughnessy.net/2015/2/16/mark-methods-private-when-you-dont-test-them)“The private keyword signals other developers: Don’t rely on this; don’t call it; it might change.” Cloud 66Sponsored[Build, deploy and manage Docker in production](http://www.cloud66.com/?utm_source=rubyweekly=email=docker)Everything you need to build, deploy and manage your applications in Docker. On your own servers and on any cloud. [![Cloud 66\](https://copm.s3.amazonaws.com/3ca44f41.png)](http://www.cloud66.com/?utm_source=rubyweekly=email=docker) Justin Weiss[A Guide to Extracting Your First Ruby Gem](http://www.justinweiss.com/blog/2015/02/17/a-guide-to-extracting-your-first-ruby-gem/)The easiest way to create a useful side project is to pull it out of an app you’re already building. But what to extract? And how do you turn it into a gem, without destroying your workflow? PJ Hagerty[Life Beyond Rails: A Brief Look at Alternate Web Frameworks for Ruby](https://blog.engineyard.com/2015/life-beyond-rails-brief-look-alternate-web-frameworks-ruby)Very brief summaries of Cuba, Trailblazer, Volt, Cramp, Ramaze, Lotus and, of course, Sinatra. Brian VanLoo[Rails Scaffold's Dangerous Defaults](http://rubyjunky.com/rails-scaffold-dangerous-defaults.html)A look at how blindly using the Rails scaffold generator can allegedly inadvertently expose data you might otherwise have thought was secret to your app. Thoughtbot[Rails on Docker](http://robots.thoughtbot.com/rails-on-docker)A look at how to get started with building and deploying Rails apps using Docker and Fig (a tool to create isolated development environments with Docker). Michal Papis[Maintainers Needed for RVM 1](https://rvm.io/blog/2015/02/maintainers-needed-for-rvm1)Michal is [making some changes while continuing work on RVM 2](http://niczsoft.com/2015/02/changes-in-my-open-source-life/). Jobs - [Ruby and JavaScript Engineer at simplabs (Munich, Germany or remote)](http://simplabs.com/jobs?utm_source=rubyweekly&utm_medium=email)simplabs is an Engineering Agency with a focus on Ruby and Ember.js. We also offer training and consulting services. We are searching for a Ruby and JavaScript Engineer in Munich, Germany or remote - junior level Engineers who are passionate about technology and willing to learn new things are welcome! simplabs - [Software Engineers at Skyscanner (remote – with 20% of time in Edinburgh, Scotland)](http://www.skyscanner.net/jobs/all?utm_source=rubyweekly&utm_medium=email)Comfortable with client MVC frameworks and have a strong grasp of modern client toolsets? Come and help us craft new products and services for Skyscanner’s 200 million visitors a year. Skyscanner - [Hired gives top Ruby developers more power in their job search.](http://hired.com/?utm_source=newsletters=rubyweekly=n-feb19_15-rubyweeklyspons=power)You'll create a profile over 1 week tech companies will apply to you! You'll get salary/equity offers upfront you're under no obligation to accept any offer. Interested? Join Hired today! Hired In brief - [ParallelCI by Codeship – Run your tests in parallel](https://codeship.com/features/parallelci?utm_source=rubyweekly&utm_medium=email) news Codeship now supports running your tests in parallel. Set up test pipelines, split up test commands and run your test suite in parallel. Learn more. CodeshipSponsored - [Using Events to Decouple Rails Applications](https://redbooth.com/engineering/patterns/using-events-decouple-rails-applications?utm_source=rubyweekly&utm_medium=email) tutorial Redbooth Engineering - [The Life of an HTTP Request in Rails](https://www.omniref.com/ruby/gems/railties/4.2.0/symbols/Rails::Application?#annotation=4084035=161) tutorial Omniref - [Using PostgreSQL and jsonb with Rails](http://nandovieira.com/using-postgresql-and-jsonb-with-ruby-on-rails?utm_source=rubyweekly&utm_medium=email) tutorial Postgres 9.4 introduced jsonb, a column type for storing JSON documents, meaning you can integrate relational and non-relational data, with performance even better than, say, MongoDB. Nando Vieira - [Passing Optional Locals to Rails Partials](http://nithinbekal.com/posts/rails-optional-locals/?utm_source=rubyweekly&utm_medium=email) tutorial Nithin Bekal - [Set Intersection in Ruby](http://tosbourn.com/set-intersection-in-ruby/?utm_source=rubyweekly&utm_medium=email) tutorial Toby Osbourn - [Using Ruby instead of sed and awk](http://nithinbekal.com/posts/ruby-sed-awk/?utm_source=rubyweekly&utm_medium=email) tutorial Nithin Bekal - [Gulp on Rails: Replacing the Asset Pipeline](http://viget.com/extend/gulp-rails-asset-pipeline?utm_source=rubyweekly&utm_medium=email) tools Dan Tello - [Arcane Knowledge Needed to Write A Test (for a Rails App)](http://blog.testdouble.com/posts/2015-02-16-arcane-knowledge.html?utm_source=rubyweekly&utm_medium=email) opinion Test Double - [Mobile App Performance: Comparing RubyMotion to J2ObjC, Xamarin and RoboVM](https://medium.com/@harrycheung/cross-platform-mobile-performance-testing-d0454f5cd4e9?utm_source=rubyweekly&utm_medium=email) opinion Harry Cheung - [youtube-dl.rb: A Ruby Wrapper for youtube-dl](https://github.com/layer8x/youtube-dl.rb?utm_source=rubyweekly&utm_medium=email) code layer8x - [RuberTooth: A Complete Ruby Port of the Ubertooth Libraries and Utilities](http://www.evilsocket.net/2015/02/12/rubertooth-a-complete-ruby-porting-of-the-ubertooth-libraries-and-utilities/#sthash.sNhWFzor.dpbs?utm_source=rubyweekly&utm_medium=email) code Ubertooth is an open source 2.4 GHz wireless dev platform for Bluetooth experimentation. Simone Margaritelli - [rails-safe-tasks: Automatically Disables Dangerous Rake Tasks in Production](https://github.com/adamcooke/rails-safe-tasks?utm_source=rubyweekly&utm_medium=email) code Adam Cooke Curated by [Peter Cooper](https://twitter.com/peterc) and [Glenn Goodrich](https://twitter.com/ruprict), and published by [Cooperpress](https://cooperpress.com/). Send feedback by simply replying to this mail. Want to sponsor an issue? See our [media kit.](https://cooperpress.com/mediakit) Want to post a job? Email us or [use our self-serve system.](https://booking.cooperpress.com/jobs) [Unsubscribe](*|UNSUB|*) | [Change email address](*|UPDATE_PROFILE|*) | [Read this issue on the Web](http://rubyweekly.com/issues/234) © Cooperpress Ltd. Office 30, Lincoln Way, Louth, LN11 0LS, UK [Email policy](https://cooperpress.com/spam.html) [Privacy policy](https://cooperpress.com/privacy.html)