--- title: "This week's Ruby news, issue 263" publication: "Ruby Weekly" issue: 263 published_at: "2015-09-10" canonical_url: "https://rubyweekly.com/issues/263" --- This week's Ruby news, issue 263 This week's Ruby and Rails news[Read this e-mail on the Web](http://rubyweekly.com/issues/263) Ruby WeeklyIssue 263 — September 10, 2015 Practicing Ruby[Safely Evaluating User-Defined Formulas and Calculations](https://practicingruby.com/articles/formula-processing)A look at Dentaku, a parser and evaluator for a mathematical and logical formula language that provides a safe way to execute user-defined mathematical formulas within a Ruby application. Starr Horne[Creating Ruby Enumerators on the Fly](http://blog.honeybadger.io/creating-ruby-enumerators-on-the-fly/)Ever since Ruby 1.9, the Enumerator class has made it possible to more easily define custom enumerators without touching the Enumerable module or define ‘each’ methods. CodebaseSponsored[Professional private code hosting for developers & teams](https://www.codebasehq.com/t/rubyweekly-160715)Codebase offers fast & reliable hosting for Git, HG & SVN repos with project management built-in. 50% off first 3 months with code RUBYWEEKLY. [![Codebase\](https://copm.s3.amazonaws.com/a10cfa0c.png)](https://www.codebasehq.com/t/rubyweekly-160715?utm_source=rubyweekly&utm_medium=email) SitePoint[Building APIs with Napa](http://www.sitepoint.com/build-apis-with-napa/)Napa is a simple framework for building Rack based APIs using Grape, Roar and ActiveRecord. It’s designed to make it easy to quickly create and deploy new API services by providing generators, middleware and a console. LoneStarRuby 2015[The Soul of Software [video\]](https://www.youtube.com/watch?v=zs0E4E83_X8)Avdi Grimm (of Ruby Tapas) gave a philosophical keynote at LoneStarRuby 2015 about how we may be at the end of the Ruby ‘boom’ and what the legacy of Ruby might be. Parker Selbert[Know Your Sidekiq Testing Rights](http://blog.codeship.com/know-your-sidekiq-testing-rights/)“You need to know which testing modes Sidekiq is packaged with and the best practices for testing both jobs and workers.” Jobs - [Software Engineer at Braintree (Chicago, IL)](https://www.braintreepayments.com/careers/chicago/software-engineer?utm_source=rubyweekly&utm_medium=email)The Braintree full-stack payment platform lets businesses build their own experiences and then scale their operations around the globe. Every time you ride an Uber or book an Airbnb, you’re using Braintree. Come join us. Braintree - [Ruby on Rails Developer, Brentwood, TN (onsite, full time)](http://www.daveramsey.com/careers/opportunities?category=Digital+Development)We are now using Ruby on Rails to help people make REAL change in their life. We are seeking developers who are interested in building the right things and building the things right. Ramsey Solutions - [Want to work on new projects? Make more money? Try a new stack? Relocate?](https://hired.com/?utm_source=newsletters&utm_medium=rubyweekly&utm_campaign=n-q3_15-petercooperpress&utm_content=options)On Hired, we'll bring the options to you. With over 2,000 pre-screened tech companies in 10 cities in the US & UK, you'll be sure to find what you're looking for. Join Hired today. Hired.com In brief - [Kickstarter Campaign for Rails Composer](https://www.kickstarter.com/projects/909377477/rails-composer-with-rails-tutorials?ref=project_link) news Daniel Kehoe wants to improve the popular Rails Composer tool - the [rewards](http://kck.st/1KzZXVC) are worth a look as they include things like GoRails, RailsClips, and other tutorials. Kickstarter - [A Chat with David Heinemeier Hansson (creator of Rails)](http://developeronfire.com/Podcast/Episodes/david-heinemeier-hansson-the-pareto-principle-and-stoic-philosophy?utm_source=rubyweekly&utm_medium=email) podcast Developer On Fire - [How to Create a Tiny Docker Image for your Ruby App](https://medium.com/iron-io-blog/how-to-create-a-tiny-docker-image-for-your-ruby-app-f8d7d622d80b?utm_source=rubyweekly&utm_medium=email) tutorial Travis Reeder - [Testing Race Conditions in Your Rails App](http://blog.arkency.com/2015/09/testing-race-conditions/?utm_source=rubyweekly&utm_medium=email) tutorial Robert Pankowecki - [The Smart Developer’s Guide to Software Errors](https://use.raygun.io/developer-guide/?utm_source=RubyLetter10&utm_medium=SponsoredLink&utm_campaign=CooperPressSept2015) tutorial Raygun has created a free guide that covers 8 aspects of error reporting & efficient error resolution. Read the guide. RaygunSponsored - [Lesson of The Day: Switching From RSpec to Minitest](http://www.3hv.co.uk/2014/02/14/lesson-of-the-day-switching-from-rspec-to-minitest/?utm_source=rubyweekly&utm_medium=email) tutorial Rahoul Baruah - [You’ve Got Mail: Action Mailer + letter_opener](http://vaidehijoshi.github.io/blog/2015/09/08/youve-got-mail-action-mailer-plus-letter-opener/?utm_source=rubyweekly&utm_medium=email) tutorial letter_opener intercepts the Rails mailer and lets you preview an email from within the browser. Vaidehi Joshi - [Keeping Your Logs From Becoming An Unreadable Mess](http://www.justinweiss.com/blog/2015/09/08/keeping-your-logs-from-becoming-an-unreadable-mess/?utm_source=rubyweekly&utm_medium=email) tutorial Justin Weiss - [Ditching Your Single Page App For...Turbolinks?](http://blog.honeybadger.io/ditching-your-single-page-app-for-turbolinks/?utm_source=rubyweekly&utm_medium=email) tutorial opinion Starr Horne - [The Best Rails Image Uploader? Paperclip vs Carrierwave vs Refile](https://infinum.co/the-capsized-eight/articles/best-rails-image-uploader-paperclip-carrierwave-refile?utm_source=rubyweekly&utm_medium=email) opinion Stanko Krtalić Rusendić - [How FutureLearn's Rails Test Suite Operates](https://about.futurelearn.com/blog/making-futurelearn/the-futurelearn-test-suite/?utm_source=rubyweekly&utm_medium=email) opinion FutureLearn - [Ruby String Basics: 4 Silent Casts](http://bparanj.blogspot.co.uk/2015/09/ruby-string-basics-ruby-silent-cast.html?utm_source=rubyweekly&utm_medium=email) video An interesting idea - silent screencasts showing off various Ruby String features (parts [2](http://bparanj.blogspot.co.uk/2015/09/ruby-223-string-basics-part-2.html), [3](http://bparanj.blogspot.co.uk/2015/09/ruby-string-basics-part-3.html), and [4](http://bparanj.blogspot.co.uk/2015/09/ruby-string-basics-part-4.html)) Bala Paranj - [Building A Spy Library, Featuring Sam Phippen](http://peertopeer.io/videos/8-sam-phippen/?utm_source=rubyweekly&utm_medium=email) video This is a paid-for video but there’s a good 6 minute sampler. Peer to Peer - [Codeship Adds Project Manager Role to Organizations Plans](https://codeship.com/?utm_source=RubyWeekly&utm_medium=Newsletter&utm_campaign=Organizations) tools We're always improving our features. You gave us great feedback on our Organizations Plans. Now, you can have better control over projects with our new Project Manager role. Give Codeship's Organizations plans a try. CodeshipSponsored - [Union Station: Web Application Health Monitoring and Performance Analysis](https://www.unionstationapp.com/?utm_source=rubyweekly&utm_medium=email) tools Phusion have released their Phusion Passenger-integrated app monitoring and performance analysis system. Phusion - [restful-client: An HTTP Framework for Micro-Services Based Environments](https://github.com/AvnerCohen/restful-client?utm_source=rubyweekly&utm_medium=email) code Built on top of Typhoeus and Service-Jynx. Avner Cohen - [Capybara Screenshot: Capture A Screen Shot for Every Test Failure](https://github.com/mattheworiordan/capybara-screenshot?utm_source=rubyweekly&utm_medium=email) code Matthew O'Riordan 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/263) © Cooperpress Ltd. Office 30, Lincoln Way, Louth, LN11 0LS, UK [Email policy](https://cooperpress.com/spam.html) [Privacy policy](https://cooperpress.com/privacy.html)