As a Full Stack Engineer, you will provide hands-on technical leadership for the development, modernization, and ongoing support of My Plan Manager, a secure business-to-business portal that plan sponsors use to access Vanguard services, administer users, and manage key plan activities. You will collaborate with product, architecture, security, and engineering partners on initiatives such as My Plan Manager modernization, Credentials as a Service, Integrated Client Experience, Investor Choice, and enhanced single sign-on capabilities.