Senior AI-Driven Full-Stack Engineer

Mainstay Labs Inc.; San Francisco (CA); On-site; USD 180,000 - 240,000; Full time

Job summary

Mainstay Labs Inc. is seeking a senior full-stack software engineer to design, build, and ship AI-powered workflow tools in a fast-paced startup environment. You will focus on production-ready AI features across the stack, with strong Python backend and React frontend responsibilities.

The role emphasizes end-to-end ownership, collaboration with product, data science, and engineering teams, and delivering scalable, reliable systems on AWS.

Qualifications

• 5+ years of production-grade software experience.

Responsibilities

• Contribute to all phases of product development, from ideation and prototyping to implementation and iteration.
• Design reliable, scalable backend services to support AI-powered features in production.
• Build and evolve scalable backend services and APIs that aggregate, enrich, and serve large, complex real estate datasets.
• Develop and refine frontend and backend product experiences that make sophisticated data intuitive, trustworthy, and actionable.
• Evaluate and benchmark LLM performance across latency, cost, accuracy, and hallucination rates.
• Own technical decisions for systems that sit at the center of Mainstay’s SaaS platform and directly influence investor decision-making.
• Partner closely with product managers, designers, data science, and data engineering to translate business needs into durable technical solutions.
• Improve system reliability, performance, and maintainability as the platform scales.
• Modernize and automate legacy real estate workflows by replacing manual analysis with software-driven insights.
• Mentor other engineers through code reviews, technical guidance, and shared ownership of team standards

Skills

AI features

Full-stack engineering

Python

TypeScript/React

AWS

Tools

FastAPI

Django

React

Next.js

Airflow

dbt

Snowflake

PostgreSQL

AWS

Terraform

GitHub

Job description

Mainstay Labs Inc. is seeking a senior full-stack software engineer to design, build, and ship AI-powered workflow tools in a fast-paced startup environment. You will focus on production-ready AI features across the stack, with strong Python backend and React frontend responsibilities.

The role emphasizes end-to-end ownership, collaboration with product, data science, and engineering teams, and delivering scalable, reliable systems on AWS.