Currently we don't plan to release SteemPeak as an open source project. We have not finalized our business plan yet so we prefer to keep it closed source to be able to add premium features in the future. Our business strategy is not built on large delegations and curation rewards, so we need to be able to create some pay per use feature and with an open source project this will be more difficult.
Of course all the features currently available for free will remain free also in the future ;)