Inspired by the internet’s revolutionary potential to make leadership and community building easier and more accessible, Lea joined Jim Gilliam and Jesse Haff in creating NationBuilder. She served as the company's Chief of Staff and then President, before becoming CEO in 2017.

Lea currently serves on the board of the Dream Corps, a social justice accelerator that houses projects including #LoveArmy, #yeswecode, #cut50 and Green for All. She also advises Isidore Electronics Recycling (now Homeboy Recycling), a Los Angeles-based social enterprise that is creating green jobs for people exiting California's correctional system.

Lea served as gamma and alumni trainer for CASC.