Senior Full-Stack Software Engineer

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. Please note that this role is operating in a hybrid working model out of our San Jose office.

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.

We’d love to chat if you have:

• 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 Angular, 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).

Visa Sponsorship: Please note that this position is not eligible for visa sponsorship. Applicants must have authorization to work in the United States without requiring visa sponsorship now or in the future.