title: Open-source field-programmable gate array (FPGA) development tools
body: <p>I want to pick up FPGA programming. I've heard all types of horror stories of proprietary tools. Is there any entirely open-source tool chain available?</p>
  
  <p>If not, how should I learn this? My background: familiar with <a href="http://en.wikipedia.org/wiki/Scheme_%28programming_language%29" rel="noreferrer">Scheme</a>, C++, assembly, and <a href="https://en.wikipedia.org/wiki/MIPS_instruction_set" rel="noreferrer">MIPS</a> architecture.</p>