Sr. Backend Software Engineer (Digital Banking)
Not Disclosed•ContractorOn-site
location_onSan Joaquin County, California, United States
Our mission is to accelerate the pace of financial innovation and build new financial products for American Express. We embrace a culture of experimentation, constantly striving for improvement and learning. We welcome diverse perspectives and people who are not afraid to challenge assumptions. Our platform streamlines the process of launching and iterating financial products, serving as the backbone for high-volume banking systems.
As a Senior Backend Software Engineer in Digital Banking, you will be a passionate problem-solver dedicated to applying your expertise across the entire software development lifecycle. You will partner continuously with stakeholders to stay focused on common goals while designing, developing, and maintaining banking systems that support high transaction volumes, security, and scalability.
In this role, you will work on a range of critical banking products, including payment systems, data & reporting, and customer account management solutions. You will champion workflow orchestration best practices and build software within a nimble agile team where you have every opportunity to make an impact on the bottom line. Your day-to-day will involve ensuring our infrastructure is safely extensible, scalable, and reliable, meeting SLAs for both external and internal users.
A key focus of this position is the design, build, and operationalization of Generative AI capabilities. You will leverage state-of-the-art tools for remote collaboration and developer happiness, implementing Retrieval-Augmented Generation (RAG) patterns to ground LLM outputs in enterprise knowledge. You will develop and integrate LLM tool/function-calling agents to orchestrate workflows across internal APIs and services while enforcing least-privilege access. Additionally, you will establish evaluation, monitoring, and guardrails for GenAI, including prompting standards, hallucination mitigation, and PII controls.
We are looking for individuals who are hands-on engineers and team players, with a demonstrated willingness to learn innovative technologies. If you are ready to enable business capabilities through innovation and take pride in how quickly you develop working software, we want to hear from you.
We consider qualified applicants regardless of background, embracing diverse perspectives to drive our mission forward.
For applications and inquiries, please contact: hirings@openkyber.com
Work model: On-site
San Joaquin County, California, United States
California
Experience with container orchestration tools like Kubernetes and Docker. Previous experience with payment systems or real-time transaction platforms. Leadership experience in a fast-paced development environment. Experience in API development for fintech applications. Experience with vector databases and search stacks (e.g., OpenSearch/Elasticsearch, pgvector, Pinecone, Weaviate) and embedding lifecycle management. Experience building LLM agents with tool/function calling, including workflow orchestration, retries, and safe fallbacks. Experience creating/operating MCP servers (or similar abstractions) to expose enterprise data and actions to LLM applications with strong authentication/authorization. Familiarity with LLM evaluation techniques (golden datasets, human review workflows, automated scoring) and safety guardrails for regulated environments. Experience with In-memory computing solutions. Experience working with streaming solutions (preferably Apache Kafka and Kafka Streams). Hands-on experience in full-stack software development. Hands-on experience in Big Data technologies, including Python, Hadoop, and Spark.
Skills: Java, Go, Multi-Threading, LLM, Prompt Engineering, Structured Outputs, Tool/function Calling, Rag, Document Ingestion, Embeddings.
Education: Bachelor's in Computer Science preferred; Master's in Computer Science preferred.
