Senior/Staff Software Engineer (Full-stack)

Mainstay is a market intelligence platform for large real-estate operators. We’re an AI-native company focused on turning complex, messy, real-world data into systems customers actually trust to make financial decisions. Mainstay was incubated at Opendoor, spun out in 2024, and recently raised a Series A led by Khosla Ventures.

We’re hiring a Senior/Staff Software Engineers, but we care more about ownership and judgment than title.

You'll work on:

• Designing and evolving foundational data models used across the platform
• Building backend services, workflows, and automation systems end-to-end
• Applying AI/LLMs pragmatically (automation, reasoning over messy inputs, decision support)
• Shipping user-facing product features tied directly to real customer workflows
• Owning problems from idea → production → iteration

Stack:

Python, TypeScript, React, AWS