Install the Nokogiri gem on Ubuntu servers

You need to install the following packages before you can build the Paperclip gem:

sudo apt-get install imagemagick librmagick-ruby

So you're getting this failure when running bundle install on an older project:

Your Gemfile.lock is corrupt. The following gems are missing from the DEPENDENCIES section: 'archive-tar-minitar' 'hoe' 'rcov'

This happens when you ar...

At makandra, we've built a few gems over the years. Some of these are quite popular: spreewald (> 1M downloads), active_type (> 1M downloads), and geordi (> 200k downloads)

Developing a Ruby gem is different from developing Rails applications, w...

• If Rails or Rake are complaining about a missing gem that is listed in your Gemfile.lock and the listed version is properly installed, something is seriously wrong and needs to be fixed.
• If you accidently executed bundle install some_gem a...

A recent patch level Ruby update caused troubles to some of us as applications started to complain about incompatible gem versions. I'll try to explain how the...

We're usually running Ubuntu LTS versions. Sometimes newer hardware requires packages from more recent Ubuntu releases that only come with 6 months of support. If there is really no other way, it's possible to install packages from later Ubuntu re...

When you're developing a gem, never list the same dependency as both runtime and development dependency in your .gemspec.

So don't do this:

spec.add_dependency 'activesupport'
spec.add_development_dependency 'activesupport', '~> 2....

First of all: You could just use RVM which would make the pain go away. If for some reason you can't, proceed.

Do not use rubygems from the apt repository.

1. Get the latest [RubyGems](http://rubygems.org/page...

Today I needed to execute a ruby gem executable with sudo. But, surprisingly, bash would tell me command not found for the gem that ran lovely without sudo.

Gem bins are installed to /var/lib/gems/1.8/bin, which is not in sudo’s PATH....