Born and raised in Seattle, Kilifi was schooled at West Seattle where he played centre before moving into the front row as he matured into his bruising size, earning High School All American honours.
Kilifi would go on to play for the Seattle Saracens at the Senior Club level and earned his way into the USA Rugby pathway. In 2013, Kilifi made his Men's Eagles debut in a win against Georgia.
While training and residing in Seatle, Washington, Kilifi debuted for the U.S. national team during the end of year tests in November 2013, earning two substitute appearances.
The prop started in both of the March 2014 qualifying matches against Uruguay for the 2015 World Cup, and was at the time considered one of the U.S. team's best scrummagers.
Kilifi was named to the USA Rugby 2015 Rugby World Cup team, playing three matches. In 2016, Kilifi signed with the Sacramento Express of PRO Rugby North America.
In January 2017, he was named in the USA squad ahead of the 2017 Americas Rugby Championship.
As of 17 November 2017 Kilifi has 20 Test caps to his name.
JW November 17
|2013 - present|
|2018 - present|
|2016 - 2017|