Might also want to change "fills roles" to "fills a role" in the following paragraph: "In the nature of transparency and open source, Bitcoin Private is developed by team members all over the world. Each member fills roles and contributes based on his or her skill sets."
Might also want to change "fills roles" to "fills a role" in the following paragraph: "In the nature of transparency and open source, Bitcoin Private is developed by team members all over the world. Each member fills roles and contributes based on his or her skill sets."