Staff Software Engineer (Backend) Rewards and Reconciliation

BILL•San Jose, CA

5h•$153,000 - $216,000•Remote

About The Position

Innovate with purpose 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 By replacing outdated financial processes with innovative tools, we help businesses—from startups to established brands—make smarter decisions and gain control of their operations.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 our dynamic Rewards and Reconciliation Squad, where we drive the accuracy and integrity of BILL’s financial operations. As a Software Engineer II, you’ll play a key role in building and enhancing systems that ensure seamless rewards processing and precise reconciliation, directly impacting customer trust and business performance. This is an exciting opportunity to develop your technical skills, collaborate with talented peers, and contribute to innovative solutions in a fast-paced, mission-driven environment.

Requirements

Requires a minimum of 8 years of related experience with a Bachelor's degree; or 6 years and a Masters degree; or a PHD with 3 years of experience; or equivalent experience
6+ years of software development experience building large-scale, complex applications.
Solid understanding of CS fundamentals, including Data Structures, Algorithms, Computer Networking, and Databases.
Proficiency in an object-oriented or functional language, with a strong preference for Elixir.
Strong knowledge of SQL Databases, particularly Postgres.
Demonstrated ability to break down and solve moderately complex technical tasks.
Effective communication skills with the ability to explain technical concepts to diverse audiences.

Nice To Haves

Expertise in using Kubernetes and AWS services to build microservices.
Experience with Flink, Kafka, or other Event-Driven Systems.
Familiarity with observability tools such as Splunk, Datadog, Mixpanel, or LaunchDarkly.
Prior experience in FinTech, banking, or payments.

Responsibilities

Design and build scalable backend services and RESTful APIs that power rewards, billing, and spend workflows, primarily using Elixir.
Analyze and resolve moderately complex technical problems to improve the accuracy of existing financial systems and processes.
Collaborate cross-functionally with product managers and stakeholders to translate complex business needs into high-quality technical solutions.
Write clear, maintainable code and technical documentation to support ongoing system reliability, scalability, and observability.
Deploy and operate microservices in AWS, and managed services to ensure security and efficiency.
Participate in code reviews and advocate for engineering best practices across the software development lifecycle.
Improve service performance and reliability through strong instrumentation, monitoring, and alerting practices (using tools like Splunk or Datadog).
Mentor junior engineers and foster a culture of continuous learning and innovation