Firstly, you have to declare the font in your CSS stylesheet:
<em class="icon-photoshop"></em> <em class="icon-mysql"></em> <span class="icon-redis"></span> <a href="#" class="icon-rails"></a>
You are welcome to add svg icons to the icons folder and submit a pull request or If you want any specific logo to be added to the list please create an issue.
Few icons are taken from mfizz.
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