> Markdown version of [/jobs/ext/2782458-senior-software-engineer](https://www.wearedevelopers.com/jobs/ext/2782458-senior-software-engineer). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Software Engineer - **Company:** Prosper Ai - **Location:** Laza, Spain - **Contract:** Permanent contract - **Skills:** Artificial Intelligence, Systems Engineering, Distributed Systems, Python (Programming Language), PostgreSQL, Machine Learning, TypeScript, ReactJS, Large Language Models, Backend, Fastapi, Information Technology, Low Latency, Front End Software Development - **Published:** September 7, 2026 - **Apply:** https://www.buscojobs.com.es/senior-software-engineer-en-laza-ID-369821735 ## About the Role 3-5 years of experience building products end-to-end, from architecting solutions to deploying production-grade software. A strong understanding of the technologies that power our stack or their equivalents in other languages: FastAPI (Python) + PostgreSQL backend with a React (TypeScript) frontend. Experience managing large scale distributed systems with asynchronous workload orchestration. Familiarity with LLMs, AI agents or other ML models is a plus. We use Pipecat for our voice agents. Founder mindset: ownership + hard work. You see Prosper as a learning step for your future startup. Be ready to handle the challenges of deploying AI voice agents to thousands of daily phone calls. Bachelor's or Master's degree in Computer Science, Engineering, Maths, Physics or related field (or equivalent experience). ## Description About Prosper AIProsper AI specializes in AI Phone Agents for healthcare, providing human-like expertise while significantly reducing costs. Our AI Agents efficiently handle tasks for calling patients and payors such as claims status checks, benefit verification, prior authorizations, patient scheduling, and balance reminders. We aim to eliminate $200B in administrative waste, allowing healthcare professionals to focus more on healing and less on administrative tasks.What you'll doAt 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 adapt instantly to messy, high-stakes healthcare conversations. As a Software Engineer, you'll be at the center of designing and scaling our platform, the low-latency speech/LLM pipelines, orchestration layers, and reliability systems that make this possible.This is a full-time role in Barcelona office with the possibility to move to the New York office.What we're looking for3-5 years of experience building products end-to-end, from architecting solutions to deploying production-grade software.A strong understanding of the technologies that power our stack or their equivalents in other languages: FastAPI (Python) + PostgreSQL backend with a React (TypeScript) frontend.Experience managing large scale distributed systems with asynchronous workload orchestration.Familiarity with LLMs, AI agents or other ML models is a plus. We use Pipecat for our voice agents.Founder mindset: ownership + hard work. You see Prosper as a learning step for your future startup.Be ready to handle the challenges of deploying AI voice agents to thousands of daily phone calls.Bachelor's or Master's degree in Computer Science, Engineering, Maths, Physics or related field (or equivalent experience).Interviewing ProcessInitial conversation to understand who you are, what you want to do, and where you wanna go (30 minutes)Work on a take-home challenge to discuss in the following interviewReview your solution with a couple of engineers from the team (60 minutes)Talk with the co-founder (60 minutes)Offer stage ## Related Videos - [Agentic employees in world's most downloaded FinTech app](https://www.wearedevelopers.com/videos/100123-agentic-employees-in-world-s-most-downloaded-fintech-app) - [Intro to FastAPI](https://www.wearedevelopers.com/videos/462-intro-to-fastapi) - [Developing the Backend with Stefan Lingler, CTO at Shpock](https://www.wearedevelopers.com/videos/100360-developing-the-backend-with-stefan-lingler-cto-at-shpock) - [Watch Tests Go Brrrr! : Getting Started with Cypress in ReactJS](https://www.wearedevelopers.com/videos/282-watch-tests-go-brrrr-getting-started-with-cypress-in-reactjs) - [Building the Next Generation of Software](https://www.wearedevelopers.com/videos/100186-building-the-next-generation-of-software) - [Building and Deploying Multi-Agent Systems with ADK and Vertex AI](https://www.wearedevelopers.com/videos/1918-building-and-deploying-multi-agent-systems-with-adk-and-vertex-ai) ## Related Articles - [How to Become an AI Engineer](https://www.wearedevelopers.com/magazine/331-how-to-become-an-ai-engineer) - [Navigating the AI Shift](https://www.wearedevelopers.com/magazine/629-navigating-the-ai-shift) - [What Are Large Language Models?](https://www.wearedevelopers.com/magazine/304-what-are-large-language-models) - [MLOps – What’s the deal behind it?](https://www.wearedevelopers.com/magazine/125-mlops-what-s-the-deal-behind-it) - [MLOps And AI Driven Development](https://www.wearedevelopers.com/magazine/82-mlops-and-ai-driven-development) - [What is Agentic Programming and Why Should Developers Care?](https://www.wearedevelopers.com/magazine/625-what-is-agentic-programming-and-why-should-developers-care)