Senior Fullstack Engineer - Mortgage Tech & AI Platform

Maxwell; United States; Remote; USD 140,000 - 190,000; Full time

Benefits offered by this job

PTO as needed

Comprehensive insurance

401(k) match

Stock options

Stock purchase plan

Job summary

Maxwell is seeking a Senior Fullstack Engineer to help scale our mortgage technology platform. You’ll work with the CTO and executives to ship features end-to-end across Rails API services, TypeScript/Node services, a GraphQL gateway, and React frontends.

You’ll own external integrations, design multi-step workflows, and lead technical decisions. The role emphasizes security, multi-tenant data isolation, on-call reliability, and mentoring, with strong focus on AI-assisted engineering and

Qualifications

• 7+ years building production web apps
• Proficient in Rails API services and API-only Rails
• Strong in React and TypeScript UI development
• Experience with GraphQL (Apollo) server/client
• Distributed event-driven systems and multi-service debugging
• Experience with third-party integrations and security
• Experience mentoring engineers and leading cross-team projects
• Familiar with AI-assisted tooling and designing for on-call reliability

Responsibilities

• Design, build, and maintain features across Rails API, TS/Node, GraphQL gateway, and React frontends
• Own integrations with external platforms (LOS, mortgage providers, e-sign vendors)
• Design and evolve async workflows using RabbitMQ, SNS/SQS, and Sidekiq
• Maintain multi-tenant security and data isolation
• Lead technical design with design docs and architecture decisions
• Improve service boundaries, test coverage, and developer experience
• Lead code reviews and engineering standards
• Participate in on-call, incident response, and root-cause analysis
• Improve observability and CI/CD pipelines
• Collaborate with Customer Support on lender escalations and data sync issues
• Partner with Product to refine requirements and edge cases
• Collaborate with UI/UX to implement accessible interfaces
• Mentor engineers through pairing and reviews
• Lead AI-assisted engineering using agentic tools daily
• Build shared AI tooling, including agent instruction files and MCP servers
• Set guardrails for AI use and data protection

Skills

Ruby on Rails

React

TypeScript

GraphQL Apollo

PostgreSQL

ActiveRecord

Background jobs

API design

AWS

CI/CD

Docker

Elasticsearch

Redis

Security

On-call

Mentoring

Tools

Node.js

GraphQL gateway

RabbitMQ

SNS/SQS

Sidekiq

Docker

AWS

Job description

Maxwell is seeking a Senior Fullstack Engineer to help scale our mortgage technology platform. You’ll work with the CTO and executives to ship features end-to-end across Rails API services, TypeScript/Node services, a GraphQL gateway, and React frontends.

You’ll own external integrations, design multi-step workflows, and lead technical decisions. The role emphasizes security, multi-tenant data isolation, on-call reliability, and mentoring, with strong focus on AI-assisted engineering and