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Maxwell is building a category-defining company at the intersection of real estate, technology, business services, and consumer products. As a profitable, hypergrowth startup on the path to IPO, they are seeking a Senior Fullstack Engineer to partner with the CTO, founders, and executives to build and scale their mortgage technology platform.
In this role, you will design, build, and maintain features across Rails API services, TypeScript/Node services, a GraphQL gateway, and React frontends. You'll own integrations with external platforms including LOS systems, mortgage insurance providers, and document/e-sign vendors, handling data mapping, sync, reconciliation, retries, and idempotency. You'll design and evolve asynchronous, multi-step workflows using message queues (RabbitMQ, SNS/SQS), Sidekiq background jobs, and saga-style orchestration patterns.
Key responsibilities include keeping the multi-tenant platform correct and secure while respecting partner boundaries; leading technical design for significant features through design docs and architecture decision records; identifying and paying down technical debt; holding a high bar in code review; joining the on-call rotation and leading incident response; using observability tools and CI/CD to maintain platform health; working directly with Customer Support & Success on lender-reported escalations; partnering with Product Managers to refine requirements; collaborating with UI/UX Designers on polished, accessible interfaces; mentoring other engineers through pairing and code review; and leading AI-assisted engineering by using agentic coding tools daily (Claude Code, Cursor, Codex) to plan, implement, test, debug, and review work. You'll also build and maintain shared AI tooling for the team, including agent instruction files, reusable skills and prompts, and MCP servers.
The company offers a "work from the place you work best" approach, competitive benefits including PTO as needed, comprehensive insurance coverage, 401(k) match, stock option grants, and a stock purchase plan. Every team member is an owner.
REQUIREMENTS:
- 7+ years building and running production web applications
- Deep expertise in Ruby on Rails, including API-only services, ActiveRecord, PostgreSQL, background jobs, and RSpec
- Comfortable shipping polished UI with React and TypeScript
- Experience with GraphQL (ideally Apollo) on both server and client
- Experience building distributed, event-driven systems and debugging failures that span services
- Proven ability to tame third-party integrations (REST, SOAP, webhooks) and partner APIs
- Strong instincts for security and multi-tenant data isolation
- Advanced daily use of AI and agentic coding tools, with ability to structure context for agents and verify output
- Strong communication skills: can write design docs, explain production incidents, and disagree productively
- Experience with on-call, incident response, observability, and blameless postmortems
BONUS EXPERIENCE:
- Mortgage tech or similar regulated, integration-heavy domain (fintech, lending, insurance, payments, healthcare)
- Familiarity with LOS platforms (Encompass, MortgageBot, Byte) or MISMO standards
- Node.js/TypeScript services, Elasticsearch, Redis, Docker, AWS, CI/CD
- Saga or workflow orchestration patterns
- History of mentoring engineers and leading cross-team projects
