Mono is a project begun by De Icaza, a co-founder of the GNOME desktop project, in August 2001. It aims to create a free implementation of Microsoft's .NET development environment.
De Icaza told SD Times that the fact Mono was the sole implementation of the common language infrastructure was testament to the legal uncertainty surrounding some aspects of .NET due to the Redmond-based company's statements about open source software.
He also claimed that Facebook, Google, Ruby on Rails and Wikipedia could have been built using .NET.
"All of those are failed opportunities. Even if the cross-language story was great, the Web integration fantastic, the architecture was the right one to fit whatever flavor of a platform you wanted, people flocked elsewhere," he was quoted as saying.
Some parts of .NET have been submitted to ECMA and are said to be available on a royalty-free, reasonable and non-discriminatory licence from Microsoft but De Icaza claimed this submission had remained at a "core level."
"It never went into other areas like server APIs, GUI APIs, or even updating some of the core to include LINQ, the DLR and many others," he was quoted as saying.