While reading an article about web design, I came across the sentence about the NDA that confused me. Please help to clear out the meaning.
"That was an open ended brief, and it led to some of the most interesting periods of exploration and pondering in my career. As far as I’m aware the workings of the preexisting typography system are still cloaked by my NDA, but it was essentially human-specified. As a reaction to this I defined my own brief as “a system that can understand, select & apply typography with the nuance of an expert human designer”. No biggie." -- http://www.jon.gold/2016/05/robot-design-school/
Does the author mean that the works that existed before he had been hired were protected by HIS non-disclosure agreement? Does "cloaked by NDA" mean the preexisting works were PROTECTED and he still can't share the details?