Senior Software Engineer (Full-Stack, Frontend) - HOA

About Mainstay

Mainstay is the leading market intelligence platform purpose built for buying, managing, and selling homes in the single family rental industry. As an AI native company, we turn complex data into clarity that helps the industry move forward with confidence. Founded within Opendoor, Mainstay launched as an independent company in 2024 and recently raised a Series A round led by Khosla Ventures.

Ready to shape the future of real estate with AI? Join Mainstay and help us redefine what’s possible in the single family rental space. If you thrive on solving complex problems and want to make a tangible impact in a fast-growing industry, we’d love to hear from you - apply now and let’s move the industry forward, together!

About the role

Mainstay’s HOA team builds the software that untangles one of the most operationally complex parts of single-family rental real estate: homeowners associations. HOAs introduce friction, risk, and manual overhead at scale - our mission is to remove that drag entirely.

As a Senior Full-Stack Software Engineer on the HOA team, you’ll help design and build systems that replace fragmented, error-prone workflows with scalable software and automation. Your work will directly impact how real estate portfolios operate - reducing costs, improving accuracy, and enabling the business to grow.

This role is intentionally full-stack, with the majority of your time (~60%) focused on building intuitive, high-leverage frontend experiences, and the remaining 40% spent designing and implementing backend services, APIs, and data models that power those interfaces. You’ll own features end-to-end, working close to the problem space, collaborating deeply with non-engineering partners, and carrying work from concept through production.

In this role you will

• Design, build, and ship end-to-end product features across frontend and backend systems that power HOA intelligence, compliance, and management workflows

• Lead the development of complex, data-heavy user interfaces that help operators understand, act on, and automate HOA-related decisions

• Build and evolve backend services and APIs that integrate with internal systems, third-party vendors, and large-scale data pipelines

• Partner closely with Product, Operations, and other Business stakeholders to deeply understand real-world pain points and translate them into durable software solutions

• Influence technical direction through pragmatic system design, thoughtful tradeoffs, and mentorship of other engineers

What we're looking for

• 5+ years of experience building and shipping production software, with meaningful experience across both frontend and backend systems

• Strong frontend expertise using React and modern TypeScript-based workflows, with a proven ability to build complex, maintainable user interfaces

• Solid backend experience designing APIs and services (e.g., Python-based frameworks like FastAPI or Django), with an understanding of data modeling and system reliability

• Excellent written and verbal communication skills, and comfort collaborating in a remote, cross-functional environment

This role is a great fit if

• You’re motivated by real operational impact, not just greenfield abstractions - your work will be used daily in high-stakes, HOA-driven operational workflows

• You enjoy owning problems end-to-end, from understanding messy inputs to delivering clean, scalable solutions

• You value close collaboration with product managers, operators, and business partners, and believe the best software comes from deep context

• You’re excited to help shape systems and patterns that will scale as the HOA product line and team grow

Not a great fit if

• You prefer working exclusively on frontend or backend with little interest in the full system

• You’re looking for narrowly scoped tasks with limited stakeholder interaction

• You’re uncomfortable operating in problem spaces that start ambiguous and require iteration, judgment, and collaboration to clarify

Tools we use

• Languages: Python, TypeScript

• Backend: FastAPI, Django

• Frontend: React

• Data: Airflow, dbt, Snowflake, PostgreSQL

• Infra: AWS, Terraform

• Tooling: GitHub Actions

#LI-AW

Mainstay Built on Trust

At Mainstay, trust is at the core of everything we do. We build trust with everyone -- from candidates to employees to partners. We believe in fairness and openness throughout our hiring process, evaluating candidates based on qualifications without regard to race, color, religion, national origin, age, gender, marital status, disability, veteran status, sexual orientation, gender identity, or any other protected status. Our privacy practices describe how we handle applicant information, you can find the policy details for California residents here.

We are committed to providing reasonable accommodations throughout our recruitment processes for candidates with disabilities, pregnancy, religious beliefs, or other reasons protected by applicable laws. If you require assistance or a reasonable accommodation, please contact us at [email protected]