Ly was co-founder of LinkedIn, a social networking site designed specifically for the business community, where he served as its founding chief technology officer.

[4] Ly graduated with distinction in 1991 with a Bachelor of Science in Symbolic Systems and as a member of Phi Beta Kappa society.

[8] In 1995, Ly co-founded Netmosphere, a software company enabling project management collaboration utilizing Internet technologies such as Java.

[10] As LinkedIn's founding CTO, Ly "helped create some of its core product features, which enabled the company to reach profitability and a quickly growing user base.

[14] The company first built a meeting scheduler chatbot described as "pure, refined, focused, with a fairly deep understanding of how real people, not just 'users,' think, act and want from their online apps.

The technology evolved into a mobile app called Presdo Match, "that facilitates networking" and "provides a searchable directory of attendee profiles (imported from LinkedIn when desirable), makes connection recommendations, and highlights which contacts from existing networks are in attendance so users can send messages and schedule meetings with other attendees.