As a Senior Software Engineer at Fountain, you will build user-centered web applications that help organizations improve employee retention. Operate with autonomy typical of early-stage product development within a globally distributed team.What you’ll be doing: Design, develop, test, and maintain features; collaborate with product/design; review peers' work; implement RESTful endpoints and Node.js/Express backend; extend MongoDB models; ensure product quality/reliability/security; optimize performance and scalability; stay current with industry trends.What you should bring: 5+ years full stack engineering; product-oriented development; proficiency in React, TypeScript, MongoDB, Express; familiarity with TailwindCSS, MUI, Vite; Ruby on Rails nice to have; Vitest/Jest, Playwright; strong problem-solving; ability to work independently; excellent English communication.Nice to Have: B2B SaaS/startup experience; event-driven/serverless/high-volume architectures; API strategies; MongoDB; AWS; micro-services; web security; Agile methods; cross-functional Agile collaboration.