React Full Stack - Senior Software Engineer

Marsh • Clayton, MO

3d • $106,000 - $159,500 • Remote

About The Position

As a Senior Software Engineer on the Marsh Agency Software Engineering team, you will design, build, and evolve full-stack capabilities for an AI-powered insurance document analysis platform. You will partner with product, design, and engineering colleagues to turn complex business needs into secure, reliable experiences. The work includes contributing to document processing, coverage-gap analysis, quote comparison, and real-time progress flows, while helping raise engineering quality through code reviews, automated testing, observability, and technical mentorship.

Requirements

• Strong experience building modern React applications with TypeScript, component-based UI design, and client-side API integration.
• Professional experience developing Python services with FastAPI and designing RESTful APIs, background processing, and asynchronous workflows with Celery.
• Ability to design secure, scalable systems that integrate with identity platforms, third-party APIs, OCR and document-processing services, and LLM-powered workflows.
• Experience with cloud-native deployment patterns, containers, CI/CD, monitoring, and production operations; AWS and Kubernetes/EKS experience is highly relevant.
• Strong communication, collaboration, problem-solving, and technical leadership skills, including a track record of mentoring engineers and delivering high-quality work.
• Hands-on experience with document-oriented or distributed data platforms such as MongoDB, Redis, and Amazon S3.

Nice To Haves

• Experience with Mastra, LLM orchestration, prompt/tool design, or AI agent workflows.
• Experience with Server-Sent Events, MongoDB change streams, OCR/document parsing, or browser-based WASM processing.
• Familiarity with Microsoft Entra ID/MSAL, infrastructure as code, or observability platforms such as Datadog.

Responsibilities

• Design, build, and evolve full-stack capabilities for an AI-powered insurance document analysis platform.
• Collaborate with product, design, and engineering colleagues to translate business needs into secure, reliable experiences.
• Contribute to document processing, coverage-gap analysis, quote comparison, and real-time progress flows.
• Participate in code reviews and improve quality through automated testing and observability.
• Provide technical mentorship to engineers.

Benefits

• Generous time off, including personal and volunteering time.
• Tuition reimbursement and professional development opportunities.
• Hybrid or remote work.
• Charitable contribution match programs.
• Stock purchase opportunities.
• Health and welfare benefits.
• Tuition assistance.
• 401K savings and other retirement programs.
• Employee assistance programs.
• Potential eligibility for performance-based incentives.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed