In a recent patch we improved Rails response time by >10%, our largest improvement to date. I'm going to show you how I did it, and introduce you to the tools I used, because.. who doesn’t want fast apps?

In addition to a speed increase, we see a 29% decrease in allocated objects. If you haven't already, you can read or watch more about how temporary allocated objects affect total memory use. Decreasing memory pressure on an app may allow it to be run on a smaller dyno type, or spawn more worker processes to handle more throughput. Let's back up though, how did I find these optimizations in Rails in the first place?

A year ago Heroku added metrics to the application...

Heroku has a strong tradition with open source projects. Engineers have dedicated countless hours to the projects that developers count on every day. Open Source Software is in our DNA.

Speaking personally, I’m passionate about building tools like AFNetworking and cupertino, in order to help developers build insanely great experiences for mobile devices. It’s with great pleasure that I introduce something new I’ve been working on:

Helios is an open-source framework that provides essential back-end services for iOS apps. This includes data synchronization, push notifications, in-app purchases, and passbook integration. It allows developers to get a client-server app up-and-running while...

With support for Node.js, Java, Scala and other multi-threaded languages, Heroku allows you to take full advantage of concurrent request processing and get more performance out of each dyno. Ruby should be no exception.

If you are running Ruby on Rails with Thin, or another single-threaded server, you may be seeing bottlenecks in your application. These servers only process one request at a time and can cause unnecessary queuing. Instead, you can improve performance by choosing a concurrent server such as Unicorn which will make your app faster and make better use of your system resources. In this article we will explore how Unicorn works, how it gives you more processing power, and how...

A serious security vulnerability has been found in the Ruby on Rails framework. This exploit affects nearly all applications running Rails and a patch has been made available.

Rails developers can get a full list of all your affected Heroku applications by following instructions here. Please address this security vulnerability by immediately upgrading your affected apps to any of the safe versions of Rails listed below. The following Rails versions have been patched and deemed safe from this exploit:

• 3.2.11
• 3.1.10
• 3.0.19
• 2.3.15

If you do not upgrade, an attacker can trivially gain access to your application, its data, and run arbitrary code or commands. Heroku recommends upgrading to a...

This past Sunday, Rails 2.3.6 was released, and quickly followed by 2.3.7 and 2.3.8. One of the major changes in these new versions is to require a newer version of Rack, specifically 1.1.0, that is incompatible with Rails 2.3.5 and older. Due to the fairly complex ways in which Rubygems resolves dependencies, this can prevent your app from starting – in your local environment as well as when deployed on Heroku. If you’ve been affected by this issue, you would see this error message:

 Missing the Rails gem. Please `gem install -v= x.x.x`, update your RAILS_GEM_VERSION setting in config/environment.rb for the Rails version you do have installed, or comment out RAILS_GEM_VERSION...