Senior Full-Stack Software Engineer

BILL•San Jose, CA

About The Position

At BILL, we believe in empowering the businesses that drive our economy. By replacing outdated financial processes with innovative tools, we help businesses—from startups to established brands—make smarter decisions and gain control of their operations. And we don’t stop there: we’re creating the future of financial automation so businesses can spend more time on what matters. Working here means you become part of a vision-driven team that’s ready to tackle challenges and build cutting-edge solutions. We value purpose, drive, and curiosity—and we thrive in a fast-paced, ever-changing environment. Whether in one of our offices in San Jose, CA, Draper, UT, or working remotely, BILLders collaborate to deliver real impact for businesses that need more time in their busy weeks. BILL builds high performing teams and we seek to hire the best talent for every role. We're committed to building a workplace that fosters inclusion and diverse perspectives, valuing each person’s unique skills and experiences. We’d love to hear from you—you might be just what we’re looking for, whether in this role or another. ✨ Let’s give businesses more time for what matters. Make your impact within a rapidly growing Fintech Company Join BILL’s Account Payables - Multi-Entity team, where we are transforming how businesses manage complex financial operations across multiple entities, subsidiaries, and locations. As a Senior Software Engineer, you’ll architect and scale innovative back-office solutions, managing enterprise-level data volumes and complex workflows that empower Lower Mid-Market Customers and Accountants to streamline operations through our flagship Multi-Entity (ME) offering. This team operates with a "startup" mentality within the broader AP operations, having built a 0-to-1 core platform in the last year that handles data across hundreds of entities with a focus on reliability, high performance, and availability. This is your opportunity to work in a collaborative, high-growth environment where your technical expertise will directly influence BILL’s vision to empower businesses through financial automation.

Requirements

Bachelor’s degree in Computer Science or a related field (Master’s a plus); typically 5+ years of professional software engineering experience
Strong understanding of large-scale web applications and distributed systems—including deployment, capacity planning, monitoring, and incident management
Proven ability to evaluate trade-offs and collaborate across teams on complex technical and business initiatives
Experience leading technical strategy for Multi-Entity SaaS platforms, with demonstrated success in scaling systems to support millions of mission-critical transactions
Full-Stack Proficiency: Hands-on experience with Angula, React or similar for front-end, and Java or TypeScript/Node.js or similar for back-end services.
AI Driven Development: Experience leveraging Gen AI technologies to accelerate software engineering by designing prompts, rigorously evaluating outputs, and integrating LLMs
Technical Breadth: Working knowledge of GraphQL, AWS (Lambda, DynamoDB, S3, SNS/SQS), microservices, and API gateway patterns.
Systems Thinking: Strong understanding of large-scale web applications, distributed systems, monitoring, and CI/CD (GitHub Actions, Jenkins).

Responsibilities

Design, develop, and maintain robust, scalable software solutions for multi-entity account payable workflows.
Collaborate cross-functionally with product managers, designers, and other engineers to translate business requirements into technical deliverables.
Analyze complex problems, break them down into manageable components, and implement effective, maintainable solutions.
Contribute to code reviews, share technical knowledge, and mentor junior team members to elevate team performance.
Proactively identify areas for process and system improvements, recommending and implementing enhancements to drive product quality and efficiency.
Ensure solutions adhere to best practices in security, reliability, and performance.
Stay current with industry trends and emerging technologies, bringing new ideas to the team.