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Maxwell Financial is building a category-defining mortgage technology platform at the intersection of real estate, technology, and consumer services. As a profitable, hypergrowth startup on the path to IPO, the company is scaling rapidly and innovating boldly.
In this Senior Fullstack Engineer role, you will partner directly with the CTO, founders, and executives to build and scale the mortgage technology platform. You'll ship features end-to-end across microservices and monolith architectures, with a focus on backend systems and third-party integrations. You'll work on complex, entrepreneurial problems and help scale the platform through technology and AI.
Key responsibilities include:
- Design, build, and maintain features across Rails API services, TypeScript/Node services, a GraphQL gateway, and React frontends
- Own integrations with external platforms (LOS systems, mortgage insurance providers, document and e-sign vendors), including data mapping, sync, reconciliation, retries, and idempotency
- Design and evolve asynchronous, multi-step workflows using message queues (RabbitMQ, SNS/SQS), Sidekiq background jobs, and saga-style orchestration
- Keep the multi-tenant platform correct and secure, respecting partner boundaries in every query and event
- Lead technical design for significant features by writing design docs and architecture decision records
- Identify and pay down technical debt, improving service boundaries, module design, test coverage, and developer experience
- Hold a high bar in code review and help set engineering standards across the team
- Join the on-call rotation, lead incident response, and follow through on root-cause fixes
- Use observability tools and CI/CD to keep the platform healthy
- Work directly with Customer Support & Success on lender-reported escalations and sync problems
- Partner with Product Managers to refine requirements and uncover edge cases
- Collaborate with UI/UX Designers to turn designs into polished, accessible interfaces
- Mentor other engineers through pairing, code review, and design feedback, including on AI-assisted workflows
- Lead on AI-assisted engineering by using agentic coding tools (Claude Code, Cursor, Codex) daily
- Build and maintain shared AI tooling for the team, including agent instruction files and MCP servers
- Set and follow guardrails for AI use: verify agent output, never expose secrets or customer data
The company offers a "work from the place you work best" approach, 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
- Experience with 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 owning production through on-call, incident response, observability, and blameless postmortems
Bonus qualifications:
- Experience in 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
