Ruby/GEM install Middleman error: The 'fast_blank' native gem requires installed build tools

Question

I'm trying to install https://middlemanapp.com/ using "gem", but getting the following error. I read the link in the error message, but I can't find any solution.

C:\Users\user1>ruby -v ruby 2.3.3p222 (2016-11-21 revision 56859) [x64-mingw32]

C:\Users\user1>gem -v
2.5.2

C:\Users\user1>gem install middleman
Fetching: bundler-1.13.6.gem (100%)
Successfully installed bundler-1.13.6
Fetching: rack-2.0.1.gem (100%)
Successfully installed rack-2.0.1
Fetching: tilt-2.0.5.gem (100%)
Successfully installed tilt-2.0.5
Fetching: erubis-2.7.0.gem (100%)
Successfully installed erubis-2.7.0
Fetching: fast_blank-1.0.0.gem (100%)
ERROR:  Error installing middleman:
        The 'fast_blank' native gem requires installed build tools.

Please update your PATH to include build tools or download the DevKit
from 'http://rubyinstaller.org/downloads' and follow the instructions

at 'http://github.com/oneclick/rubyinstaller/wiki/Development-Kit'

Answer 1

You probably don't have the Ruby DevKit installed on your computer or you haven't proper edited the generated config.yml from Devkit installation.

You can download the Ruby DevKit from http://rubyinstaller.org/downloads. Download the right one for your version of Ruby:

• Ruby 2.0.0 and above (32bits): mingw64-32-4.7.2
• Ruby 2.0.0 and above x64 (64bits): mingw64-64-4.7.2

After downloading, run it to extract it somewhere (permanent). Then, using the terminal, move to the folder where devkit in located: cd DevKit, then run in terminal:

ruby dk.rb init

Now you have to edit your config.yml file located in the devkit folder and add the absolute path to any installed Rubies to be enhanced to work with the DevKit, that were not automagically discovered. Eg: - C:/Ruby22-x64

Finally, you must run the following instruction:

ruby dk.rb install

More info about DevKit instalation here: https://github.com/oneclick/rubyinstaller/wiki/Development-Kit