Senior Software Engineer, API Enablement

Upstart

19h•Remote

About The Position

At Upstart, we’re united by a mission that matters: to radically reduce the cost and complexity of borrowing for all Americans. Every day, we bring creativity, experimentation, and advanced AI to reshape access to credit, helping millions move forward financially with clarity and confidence. As the leading AI lending marketplace, we partner with banks and credit unions to expand access to affordable credit through technology that’s both radically intelligent and deeply human. Our platform runs over one million predictions per borrower using more than 1,800 signals, powering smarter, fairer decisions for millions of customers. But the numbers only hint at the impact. Every idea, every voice, and every contribution moves us closer to a world where credit never stands between people and their financial progress. We’re proudly digital-first, giving most Upstarters the flexibility to do their best work from wherever they thrive, alongside teammates across 80+ cities in the US and Canada. Digital-first doesn’t mean distant. We’re intentional about in-person connection through team onsites, planning sessions, and moments that spark creativity and trust. And whether you choose to work primarily from home or collaborate in-person from one of our offices in Columbus, Austin, the Bay Area, or New York City (opening Summer 2026), you’ll have the support to work in the way that works best for you. If you’re energized by tackling meaningful problems, excited to innovate with purpose, and motivated by work that truly matters, we’d love to hear from you. Upstart’s Event Bus, Experimentation, and gRPC team is responsible for building frameworks and tooling to support Event Driven Architectures, safe and measurable roll out of new features, and efficient service to service communication. We do this by owning the build process and libraries for the four primarily supported languages at Upstart (Ruby, Kotlin, Python, and TypeScript). These platform products allow Upstart engineers to use them in a simple and secure way. Ease of use, performance, data quality, observability, and security are our guiding principles. As a Senior Software Engineer on Upstart’s Event Bus, Experimentation, and gRPC team, you are empowered to design and implement high impact, cross cutting solutions that touch nearly every service within Upstart. We are a small and high impacting team contributing to Upstart’s North Star Architecture and need a product-oriented engineer who is excited to contribute across Event Bus, Experimentation, and gRPC internal tooling.

Requirements

Bachelor’s degree in Computer Science, Engineering, or Mathematics, or a related field (or its equivalent) + 4 years of experience
Strong communication skills and ability to collaborate effectively with cross-functional teams.
Strong proficiency in one or more of Kotlin, Java, Python, Ruby, or Typescript programming languages
Proficiency in automated testing patterns
Experience in building highly observable systems

Nice To Haves

Experience with Kotlin, Python, Ruby, or Typescript
Experience with Kafka
Experience with gRPC
Experience with A/B testing and/or Feature Flagging
Strong sense of ownership and accountability for the quality and timely delivery of work
Ability to thrive both in self-directed work environments and in collaborative settings, contributing positively to team dynamic.

Responsibilities

Lead the design and development of new features and improvements to existing features.
Collaborate with cross-functional teams to understand requirements and bring those insights into building an impactful roadmap for the team
Establish best practices for achieving an Event Driven Architecture, safe feature rollout, and service to service, API design.
Mentor junior engineers and promote a culture of technical excellence
Contribute to quality improvements within our team and the engineering organization in a meaningful way

Benefits

Competitive compensation, including base pay, bonus opportunities, and annual equity grants that vest quarterly
Generous 401(k) plan with Upstart matching $2 for every $1 contributed, up to $15,000 per year
Employee Stock Purchase Plan (ESPP) with discounted stock purchase options for eligible employees
Affordable medical, dental, and vision coverage, with multiple plan options - Upstart covers 90% to 100% of the cost depending on the plans you choose
Health Savings Account contributions from Upstart for eligible plans
Income protection benefits, including company-paid Basic Life, AD&D, and Short- and Long-Term Disability coverage, with options to purchase supplemental coverage
Paid time off, sick and safe time, and company holidays
Paid family and parental leave to support caregiving and major life moments
Family-centered benefits through Carrot and Cleo, supporting fertility, parenthood, and caregiving
Employee Assistance Program (EAP) offering mental health support and life-centered resources
Financial wellness resources, including access to financial planning tools and a financial concierge service
Annual wellness allowance to support your physical and emotional well-being and personal development, based on what matters most to you
Annual productivity allowance to invest in relevant tools and resources you need to do your best work, no matter where you work from
Connection and community through team events and onsites, all-company updates, and employee resource groups (ERGs)
Onsite perks, including catered lunches and fully stocked micro-kitchens when working from one of our four offices, located in the Bay Area, Austin, Columbus, and New York City (opening Summer 2026!).