You will architect and own the technical systems for autonomous AI employees replacing manual real estate workflows. From Python backends orchestrating LLMs to real-time voice infrastructure and Next.js interfaces, you will ship production features in days. This high-intensity role requires end-to-end ownership in a fast-paced, six-day-a-week startup environment.
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Full-Stack Engineer at Letty
Are you ready for the hardest, most rewarding job of your career? We are building the definitive AI agent layer for the $1T real estate industry, replacing manual spreadsheets and missed calls with autonomous AI employees. Backed by Entrepreneurs First and top-tier VCs, we operate with an intense YC-stage culture in Hoxton, London. We are looking for an elite Full-Stack Engineer to own our entire technical stack—from Python LLM orchestration to real-time voice infrastructure. If you thrive in high-intensity, 6-day-a-week environments and want to ship features in days rather than months, this is your chance to secure a founding-level role with meaningful equity.
About this role
Role overview
About the company
Letty
Letty is rebuilding the real estate agency model with domain-specific digital workers that handle tenant engagement, landlord services, compliance, and maintenance.
What you'll do
What you will do
- Architect and scale the Python/FastAPI backend and LLM orchestration pipelines that power autonomous real-time voice and messaging agents.
- Build and maintain mission-critical integrations with global telephony providers, WhatsApp, and industry-standard property management CRM systems.
- Ship user-facing features on a Next.js/TypeScript stack, ensuring high performance and reliability for agents operating 24/7.
Who you are
Who this is a fit for
- Proven track record of shipping production-grade systems using Python (FastAPI), TypeScript (Next.js), and AWS infrastructure.
- Experience with LLM orchestration, RAG pipelines, or real-time voice/STT/TTS infrastructure in a fast-moving, high-stakes environment.
- Thrives in high-intensity settings, willing to commit to a six-day-a-week in-office schedule to outpace the market and scale rapidly.
Why this role
Why this role is remarkable
- Join a high-intensity, YC-style culture backed by Entrepreneurs First and top-tier VCs with active traction in both the UK and US markets.
- Work at the bleeding edge of AI, building autonomous agents that handle complex tenant engagement, compliance, and maintenance tasks without human intervention.
- Massive ownership and equity in a mission to rebuild the technology layer of a $1T+ industry from the ground up.
Jack & Jill
How Jack & Jill work together
I get to know what you’re great at, then find roles you’d never find yourself.Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
I recruit from Jack’s network and make the intro when I spot a great match.And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.
Meet Jack
Jack gets to know what you're great at and what you want next, then searches 15 million jobs daily and helps you discover roles at companies like this.
How does this work?
Jack’s an AI agent for job searching and career coaching. He works for you.
Jill is the AI recruiter working for the company. She recruits from Jack’s network.
If it’s a match and the company wants to meet you, they’ll make the intro. In the meantime, if you’d like, Jack will send you excellent alternatives.