This is the process to get your pull request merged into one of the D git repositories.
Anyone may review your pull and raise issues. Either fix the issues or address why you did it that way. Try to follow the general style of the project. Pulls have sometimes languished for months, so be patient, as we don't have enough reviewers.
There are a dozen or so people with commit access who can decide the pull is ready for merging. Once the review seems to be over and if the pull appears worthwhile, they'll let the pull sit for a day or two to gather any further comment and then merge if there's none.
Walter has final say on pull requests for dmd, particularly those that will add new features or break code.