Mouallem cofounded All Girls Code with Moussa in 2017 to empower girls in Lebanon and the MENA region through free training in coding, technology, and leadership. The initiative has supported more than 2,500 young participants and operates in partnership with the American University of Beirut (AUB), while finalizing its nonprofit status in Lebanon. All Girls Code is primarily funded through awards and grants, and in September 2025 it received the UNESCO Prize for Girls’ and Women’s Education, which included a $50,000 grant.