Senior Founding Full Stack Engineer | AI Voice Agents San Francisco, CA | On-site, 5 days a week | $200K–$280K base + equity Build the future of AI-powered customer conversations We're partnering with a profitable, venture-backed AI company in the San Francisco Bay Area that's transforming enterprise customer service through advanced, voice-based AI agents. With a team of fewer than 50 people, the company is building production-ready AI solutions for major U.
S. enterprises. This is an opportunity to join a small, high-impact engineering team where your work directly shapes the product, architecture, and technical direction of the business. The Opportunity As a Senior Founding Full Stack Engineer, you'll take end-to-end ownership of core product features, from architecture and development to deployment in production. You'll work directly with the founders to build high-performance applications and the infrastructure powering real-time AI voice interactions. This role is ideal for an engineer who combines strong frontend expertise with solid backend skills and thrives in a fast-paced, early-stage environment.

What you'll do
• Design and build core features for AI voice agents, including prompt orchestration, real-time dashboards, and analytics platforms.
• Develop high-performance frontend applications using React and TypeScript.
• Build backend services, APIs, and integrations supporting enterprise-scale customer conversations.
• Integrate telephony and real-time communication systems.
• Own the full software development lifecycle, from system design to production deployment.
• Optimize application performance, state management, and real-time data visualization.




• Work directly with founders and enterprise customers to deliver reliable, production-ready solutions. What We're Looking For
• 3–8 years of professional experience in full-stack software engineering.
• Strong expertise in React and TypeScript, particularly in building performant frontend applications.
• Solid backend engineering experience; programming language is adaptable.
• Proven ability to own features end-to-end, including architecture, API development, and deployment.
• A Bachelor's degree in Computer Science or Computer Engineering from a top-tier academic program, with a minimum GPA of 3.8/4.0 or equivalent.
• Willingness and ability to work on-site in San Francisco, five days per week. Nice to Have
• Experience with voice, telephony, or real-time communication technologies such as Twilio, SIP, or WebRTC.
• Experience building products powered by LLMs or AI agents.
• Experience as an early engineer at a fast-growing startup. Compensation & Benefits
• $200,000–$280,000 annual base salary
• 0.25%–0.45% equity
• 100% employer-paid medical, dental, and vision insurance.
• $10,000 relocation package.
• Visa sponsorship available for eligible candidates under H-1B, TN, L-1, E-3, and O-1 categories.
• Daily meal allowance and reimbursements for gym, commuting, phone, and internet expenses. Why Join? You'll have the opportunity to shape a core AI product, work directly with company founders, and make meaningful technical decisions in a small team where engineering has a direct impact on business outcomes. If you're a strong full-stack engineer who enjoys building from the ground up and shipping production-grade AI products, we'd love to hear from you.

📌 Full Stack Engineer (Canada)
🏢 Mission.dev
📍 Canada