Mid Forward Deployed Engineer

About Prosper AI

Prosper is building the most advanced conversational AI agents for healthcare — human-like phone agents that handle the administrative work draining the system: claims status checks, benefit verification, prior authorizations, patient scheduling, and balance reminders. Our mission is to eliminate $200B in administrative waste so healthcare professionals can focus more on healing and less on paperwork.

Headquartered in New York with an office in Barcelona, we work with dozens of large and enterprise healthcare organizations, and we've raised $35M from top investors including a16z, Base10, YC, and Emergence. We're a highly motivated team of 40 — ex-MIT, HBS, Bain, and Math/CS/Physics olympiad medalists — and as we prepare for our next stage of growth, we're looking for ambitious, exceptionally talented people to help scale our product and grow with us.

What you'll do

At Prosper, we're pushing the limits of what's possible with real-time AI. We're not just making voice agents that "talk" — we're engineering systems that sound human, reason under strong latency constraints, and integrate seamlessly with our customers' complex internal tools. As a Forward Deployed Engineer, you'll work side by side with our AI PMs to find technical opportunities that increase the performance of our agents for each of our clients.

Day to day, you'll:

• Build features that ship fast — develop new capabilities, MVPs, and internal tooling across our FastAPI (Python) + PostgreSQL backend and React (TypeScript) frontend, with a bias toward getting things in front of clients quickly.
• Integrate with messy real-world systems — build and maintain integrations with EHRs and payor systems (and the APIs, edge cases, and quirks that come with them) so agents fit seamlessly into each client's stack.
• Debug live, high-volume systems — diagnose and resolve issues for agents making thousands of daily phone calls, where reliability and call quality directly affect patient and provider experience.
• Turn client feedback into product — close the loop with AI PMs and engineering, surfacing patterns across clients and feeding them back into the core platform.
• Tune and optimize voice agents — iterate on LLM prompting, voice and transcription configuration, and conversation logic to make agents sound more human and perform reliably under real-time latency constraints.
• Manage multiple clients at once — prioritize across competing deadlines while keeping quality high.

What we're looking for

• 3+ years experience with software development
• A good understanding of the technologies that power our stack or their equivalents in other languages: FastAPI (Python) + PostgreSQL backend with a React (TypeScript) frontend.
• Experience working closely with clients and finding creative solutions to their needs.
• Familiarity with LLMs, AI agents or other ML models is a plus.
• Founder mindset: ownership + hard work. You see Prosper as a learning step for your future startup.
• Be ready to handle the challenges of supporting AI voice agents making thousands of daily phone calls.
• Bachelor’s or Master’s degree in Computer Science, Engineering, Maths, Physics or related field (or equivalent experience).

What We Offer

• The opportunity to work alongside an experienced team that has built and scaled a fast-growing, Series A company backed by top Silicon Valley investors
• Work on innovative products that are transforming US healthcare operations and sit at the heart of conversational agents.
• Significant growth opportunities as the company scales and the team takes on increasing ownership
• Competitive compensation
• Join an international team based in the heart of Barcelona
• Have real ownership and impact from day one
• Be part of a culture that rewards bold thinking, analytical rigor, and tangible results
• Flexible environment

Interviewing Process

1. Initial conversation to understand who you are, what you want to do, and where you want to go (30 minutes)
2. Work on a take-home challenge to discuss in the following interview
3. Review your solution with a couple of engineers from the team (60 minutes)
4. Talk with the co-founder (30 minutes)
5. Offer stage

This is a full-time role in Barcelona office (3-4 days in office).