# Dependency error... kramdown-math-MathJax

I got the following message trying to build my site:

Dependency Error: Yikes! It looks like you don't have kramdown-math-MathJax or one of its dependencies installed. In order to use Jekyll as currently configured, you'll need to install this gem. If you've run Jekyll with bundle exec, ensure that you have included the kramdown-math-MathJax gem in your Gemfile as well. The full error message from Ruby is: 'cannot load such file -- kramdown-math-MathJax' If you run into trouble, you can find helpful resources at https://jekyllrb.com/help/!
Conversion error: Jekyll::Converters::Markdown encountered an error while converting '_posts/2017-05-15-first-blog-post.md':
kramdown-math-MathJax
ERROR: YOUR SITE COULD NOT BE BUILT:
------------------------------------
kramdown-math-MathJax
------------------------------------------------
Jekyll 3.8.5   Please append --trace to the build command
for any additional information or backtrace.
------------------------------------------------


I have to remove the reference to MathJax as math engine from my _config.yml to make it work.

kramdown:
math_engine: MathJax
preview: false
preview_as_code: false


Does anyone know what is going on?

Thanks!

OK… I just figure it out… it was the caps on the MathJax… it should all in small letters mathjax. Funny thing it was working just fine till I update to kramdown 2.1.

How are you using Jekyll?
The last released version jekyll-3.8.5 has kramdown locked to the 1.x series. You shouldn’t be able to use kramdown-2.1 at all…

I’m using the master version

gem "jekyll", github: "jekyll/jekyll" # allow to build Jekyll faster.


because it’s decrease significantly the building time, as explained here: How I reduced my Jekyll build time by 61%

PS/ of course I’m not building it with gh-pages, but in travis.

Jekyll-4.0.0.pre.alpha1 has been released, along with a document detailing what to know when using the new version: https://jekyllrb.com/docs/upgrading/3-to-4/

Besides, now that master is at a different version altogether, do note that your plugins may not work since they may still be locked to v3.x.y.

Oh great!

Thanks a lot for the info! I think I need it because I got another error today.