Senior Software Engineer (LLM, AI)

JOB TITLE: Senior Software Engineer**TOP 3 SKILLS:**LLM, AI, Golang or C#, System DesignLOCATION: Fremont, CADURATION: 6+ Month Contract to HireRATE RANGE: $60-70/hourPOSITION SUMMARY:As a Senior Software Engineer on our client's FinTech Team, you will be the hands-on force behind the systems that monetize our client's global operations. Whether you are building real-time payment gateways, architecting massive-scale reconciliation engines, or designing automated invoicing systems, your work will directly impact the company's bottom line. This is a builder s role. We are moving beyond legacy financial stacks to create an autonomous, AI-driven financial nervous system. You will face unique challenges in distributed transactions and data consistency handling billions in revenue from vehicle orders and Supercharging to the emerging complexities of the Robotaxi fleet. You will also be among the first to bring AI Agents out of the "prototype" phase and into mission-critical financial workflows, directly reducing the operational load for our finance and support teams.RESPONSIBILITIES:Take ownership of core services within the FinTech ecosystem spanning payments processing, financial reconciliation, or billing/invoicing writing high-performance code that scales to handle global transaction volumesArchitect robust microservices and event-driven workflows, making key technical decisions on data modeling, API design, and consistency patterns like idempotency in financial transactionsMove beyond theory to practice by integrating LLMs and AI Agents directly into our stack to automate complex tasks like invoice matching, anomaly detection in ledgers, and support triageMaintain the health of your services in production using observability tools (Prometheus, Grafana) to ensure 99.99% availability and rapid incident resolution ("You build it, you run it")Raise the bar for code quality by conducting thorough code reviews, writing comprehensive tests, and mentoring junior engineers to help them grow their technical skillsWork closely with Product Managers and Finance counterparts to understand business requirements, such as new market expansions or tax regulations, and translate them into technical specificationsHelp migrate legacy workflows to modern orchestration engines (like Temporal), reducing technical debt and increasing system reliabilityREQUIREMENTS:Degree in Computer Science, or equivalent experience with 5+ years of hands-on software engineering experienceExpert-level fluency in backend development with a strong preference for Go (Golang) or C#, though we are open to other modern languagesExperience building systems that survive hardware failures, with an understanding of concurrency, database locking, caching strategies, and eventual consistencyComfortable working with Docker and Kubernetes in a production environment, including configuring CI/CD pipelines (Jenkins, Argo) to ship code safely and frequentlyPractical experience or a strong personal interest in building with AI tools (OpenAI API, LangChain, Vector DBs) and a desire to make non-deterministic AI models reliable enough for financial dataExperience with workflow orchestration tools like Temporal, Cadence, or Airflow is a major plusA pragmatic engineering mindset that prioritizes simple, maintainable solutions over complex over-engineeringBENEFITS SUMMARY: Individual compensation is determined by skills, qualifications, experience, and location. Compensation details listed in this posting reflect the base hourly rate or annual salary only, unless otherwise stated. In addition to base compensation, full-time roles are eligible for Medical, Dental, Vision, Commuter and 401K benefits with company matching.