I've been using DuckDuckGo as my primary search engine since it was introduced to me by a colleague in Chicago. This was before I was able to close my Google account but some time after losing hundreds of photos leaving Facebook. And though I was aware DuckDuckGo maintains a hidden service for Tor users it wasn't until recently I felt confident enough with my OS security to safely use it.
Rather than just bookmarking and using the DDG onion site, however, I decided to leverage some of the nifty URL params they've made available. Following is a quick rundown of the URL params I'm using to customize my DDG search experience for use with Tor. In After Dark fashion I've decided to name them “DarkDuckGo”.