Full Stack Developer (AI-Native)

JMAC Lending•Costa Mesa, CA

2d•$90,000 - $130,000•Remote

About The Position

About JMAC Lending: At JMAC Lending, we pride ourselves on over 25 years of dedicated service. Our mission is to provide exceptional support and innovative solutions that empower our partners to thrive. We’re not just about meeting today’s market demands; we aim to be the preferred lender that clients turn to again and again. Our talented team boasts impressive credentials, continuously enhancing their skills through ongoing education, ensuring a perfect blend of knowledge and experience. Built on a foundation of the highest ethical standards, we are committed to delivering competitive product pricing with efficiency and precision for wholesale and correspondent lending. The Opportunity: This position will build and maintain the applications behind JMAC Lending’s modern application platform, including the broker portal, internal workflow tools, dashboards, and AI-powered features, on a current TypeScript stack. Reporting to the IT Manager on a small applications team, this position owns assigned problems end to end: front-end and back-end development, integrations with our loan origination system and third-party platforms, workflow automation, and ongoing support of what it ships. JMAC works AI-natively, and this position is expected to use AI coding assistants well while retaining full responsibility for understanding, debugging, and defending everything delivered, regardless of who or what wrote the first draft. This is a Full-Time/Remote opportunity with varying working hours from 8-5pm PT Monday-Friday offering competitive pay ranging from $90,000-130,000 annually and is also eligible for an annual discretionary bonus.

Requirements

3+ years building and shipping web applications, or equivalent demonstrable project experience; what has been built is weighted over exact years.
Works independently once the problem is understood.
Work that can be walked through: a portfolio, GitHub, or work samples — or, where the best work is proprietary, an architecture walkthrough of a system built but not shareable.
Ability to explain how something built works and why the choices were made, not only that it runs.
Fluency with AI coding assistants (Claude Code, Cursor, Codex, or similar) paired with full ownership of the result: able to understand, debug, and defend the code regardless of who wrote the first draft. AI-assisted work in a portfolio is expected, not a caveat.
Comfort working where a feature’s intended behavior is defined by test cases and real-world feedback rather than a fixed specification document. No prior LLM-evaluation experience required; curiosity about the domain matters more.
Strong fundamentals in HTML, CSS, and TypeScript/JavaScript, with hands-on React; Next.js and Tailwind CSS a strong plus.
Back-end API experience in at least one of Node.js, C#, or Python, plus working SQL and relational schema design; Postgres ideal.
Git and pull-request workflows, with clear written and spoken communication across technical and business teams.
Must be authorized to work in the United States.
Company systems and borrower data may be accessed only from JMAC-provided, centrally managed equipment.

Nice To Haves

Next.js App Router
an ORM such as Prisma, or Supabase
Azure (Functions, Logic Apps, Key Vault, Blob Storage) or Vercel
automated testing (Vitest or Jest) and CI/CD pipelines
exposure to evaluating LLM or retrieval systems, including golden sets, regression suites, and refusal and hallucination testing
Python, especially PDF or document processing, or C#/.NET
experience building real-time or streaming UIs using server-sent events, WebSockets, or similar
background in mortgage, fintech, or another regulated industry, or eagerness to learn the domain

Responsibilities

Build and maintain internal and partner-facing applications, including the broker portal, dashboards, and workflow tools.
Develop front end in React, Next.js, TypeScript, and Tailwind CSS, owning interaction and visual quality: layout, states, empty and error cases, responsiveness, and accessibility.
Develop back-end services and APIs on Azure Functions and Node.js/TypeScript, with Python or C#/.NET for specific services; work in Postgres through an ORM, writing queries and evolving schemas.
Build AI-powered features with real-time streaming responses and keep them correct as prompts, models, and knowledge bases change.
Help build the tooling layer that allows AI assistants and agents to securely operate internal systems and data.
Implement role-based access control, audit logging, and input validation so sensitive workflows remain secure and compliant.
Write tested, reviewed code and follow the team’s version control, CI/CD, and code review practices.
Design and maintain integrations between internal systems, the loan origination system, and third-party platforms including e-sign and email.
Build workflow automations using Azure Logic Apps, Power Automate, and low-code tools; monitor and optimize existing automations.
Keep integrations within the mortgage industry’s data governance, security, and compliance requirements.
Support the applications and automations owned by this position and the team: triage tickets, fix bugs, monitor application health, and coordinate releases. This is a regular part of the week; you support what you ship.
Own assigned problems end to end: understand how the work actually gets done, propose the solution, and stay accountable for whether the shipped result improved the outcome.
Treat documentation as part of finishing: update architecture notes, API references, and diagrams in the same change that ships the code. Log a changelog entry per change and a release note when users can see it.