Principal Mobile Engineer, Cash Line

About Upstart

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 3,000 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.

The Team:

Upstart's Cash Line team builds and scales the mobile experiences that support our Cash Line products. This role will strengthen the team's mobile foundation across its codebase and help drive a newly approved Android app launch on an aggressive timeline this year. The work is highly cross-functional and high-visibility, with direct impact on product strategy, engineering execution, and the customer experience.

As the Principal Mobile Engineer on the Cash Line team, you will be the senior technical owner for the team's mobile work. You'll operate primarily as a mobile generalist and React Native specialist, elevating the team’s mobile codebase while bringing the native Android depth needed to lead the Android launch this year. After launch, you’ll continue as the team’s mobile specialist, shaping long-term mobile architecture and quality across React Native and native Android surfaces.

This is a high-impact individual contributor role with meaningful technical leadership, cross-team influence, and mentorship responsibility.

How you'll make an impact

• Serve as the primary mobile engineer and React Native specialist for the Cash Line team, raising the quality, scalability, and velocity of the team’s mobile codebase.

• Lead Android development for the team and help deliver against Upstart’s approved Android launch plan this year, translating ambitious business goals into pragmatic technical milestones and execution plans.

• Set technical direction for the team’s mobile architecture, evolving a strong foundation across React Native and native Android surfaces.

• Partner closely with product, design, and engineering stakeholders to translate roadmap priorities into durable mobile solutions.

• Raise the bar for engineering excellence through technical leadership, design reviews, mentorship, and pragmatic execution in ambiguous, high-visibility problem spaces.

• After launch, continue as the team’s mobile specialist, bringing broad React Native fluency alongside deep Android expertise to support the full Cash Line mobile stack.

Minimum Qualifications

• 8+ years of software engineering experience, including substantial experience building and shipping mobile applications with React Native and Type Script.

• Strong native Android depth in Kotlin and/or Java, with experience shipping or launching native Android applications in production.

• Proven track record leading cross-team mobile initiatives, platform migrations, or new mobile product launches in production environments.

• Experience shipping consumer-facing mobile products at scale with strong attention to performance,…