I do all the "mastering" myself, but I work in a way that doesn't typically involve much of a "mastering process." I do all of my compression and gain staging throughout my mixing process and prefer it that way because I clearly indicate what the finished product will sound like as I am creating it. My master channel is usually just a limiter or soft clipper of choice (depending on the genre or loudness level I am trying to pump out) and a mid/side EQ that removes a few particularly egregious low/mid frequencies from the sides of my mix.