Sr. Software Engineer, Backend

As a Senior Backend Engineer on the Personal Loans team, you will own the borrower-facing experiences that drive Prosper's core business -- from rate check through funding. Using modern web and mobile technologies, you will build and maintain the applications that guide borrowers through one of the most important financial decisions they'll make. Your work will directly impact conversion, borrower satisfaction, and Prosper's top-line growth.

We are investing heavily in AI across our engineering organization -- from AI-assisted development workflows to intelligent borrower experiences. You'll be joining a team that actively embraces AI tools to accelerate delivery, improve code quality, and explore new ways to make the borrower journey smarter and more personalized

We are a collaborative, high-ownership team that blends startup speed with the rigor required by a regulated financial platform. We ship often, measure everything, and care deeply about the people who use what we build.

How you’ll make an impact

• Collaborate within a cross-functional team that includes product, design, frontend engineering, and quality engineers to deliver seamless borrower experiences across web and mobile.
• Own projects end to end -- from technical design and architecture through launch, iteration, and measurement -- driving outcomes that move the business forward.
• Build and evolve our high-performance Java and Kotlin microservices, deploying scalable features across our modern Spring Boot stack.
• Decommission legacy systems (like .NET message brokers) and design modern event-driven architectures (like GCP Pub/Sub) that accelerate development across multiple product teams.
• Partner with frontend and platform engineering teams to integrate client applications with secure, performant REST and GraphQL APIs.
• Identify and drive improvements in system latency, database query optimization, testing coverage, and cloud infrastructure efficiency.
• Uphold high standards of code quality and user experience while iterating rapidly in a regulated environment.
• Leverage AI-powered tools (coding assistants, automated testing, code review) to amplify your productivity and help establish best practices for AI-assisted development across the team.
• Contribute to a strong, inclusive engineering culture by mentoring peers, championing best practices, and participating in thoughtful code reviews.

Skills that will help you thrive

• Senior Engineering Expertise: BS in EE/CS with 8+ years of experience or MS in EE/CS or other applicable disciplines with 6+ years of experience  
• Enterprise Backend Mastery: Deep proficiency in Java, Kotlin, and the Spring Boot framework, with the versatility to design, build, and scale distributed microservices.
• Robust Data Integration: Hands-on experience with RESTful APIs, GraphQL, and event-driven patterns (such as GCP Pub/Sub) to power high-performance applications.
• Modern Cloud Infrastructure: Familiarity with cloud-native architectures (specifically GCP, Firestore, Spanner, and Cloud Functions) and modern CI/CD pipelines to maintain a high-velocity development environment.
• Quality & Testing Rigor: Disciplined approach to automated testing (unit, integration, and contract tests) and system observability to ensure services are meticulous, secure, and trustworthy.
• AI-Forward Mindset: Active use of AI coding assistants (Cursor, Copilot) and a commitment to exploring new AI developments to enhance team productivity and solve product problems.
• Extreme Ownership: A proactive, high-accountability approach to driving projects to completion and unblocking yourself to deliver outcomes, not just outputs.
• User-Centric Advocacy: A deep focus on system reliability and financial accuracy, sweating the details to protect the "borrower behind the screen" and preserve trust in a regulated domain.
• Collaborative Leadership: Excellence in cross-functional communication and a dedication to elevating the team through clear mentorship and knowledge sharing.

Resources to help you prosper

A connected experience: We prioritize high-touch collaboration and flexibility. Whether you are working from our San Francisco or Phoenix offices or joining us as a fully remote team member, we provide the digital-first tools and intentional culture to keep you synced and supported
Invested in your future: A competitive salary and a 401(k) with a 5% company match to help you build long-term financial security
Holistic well-being: We provide the resources you need to thrive, from flexible time off and paid parental leave to an annual wellness allowance and comprehensive health coverage
Professional & personal growth: Take advantage of a suite of premium perks, including Udemy access, childcare assistance, pet insurance, and a bevy of additional savings through Beneplace

Interview Process

Recruiter Call: A brief screening to discuss your experience and initial questions
Technical Interview: Deeper dive into coding skills.
Team Interview: Meet team members for collaborative discussions, problem-solving, or technical exercises.