Founding Engineer

About the job

The basics

£80K\-£110K base \+ meaningful founding equity

Aldgate, London. In\-office 5 days a week

We're hiring a Founding Engineer to help build the core product behind cinnamon's AI workforce.

This is an early engineering hire with real ownership. You'll work across the product end\-to\-end, from the interfaces customers use every day to the backend systems, agents, data pipelines and integrations that power them.

You'll make product and technical decisions independently, ship quickly, and own what you put into production.

We're not looking for someone who wants to pick tickets off a backlog. We want someone who can take a problem, understand the customer need, design the system, build it, ship it, and make sure it works.

What we're building

Property is one of the most important parts of people's lives. It's where you raise your kids. It's most people's biggest financial decision. And the experience of buying, selling, or renting one is still shockingly bad.

We live in a world where you can send money across borders in three seconds, hail a car with a tap, and have your entire medical record on your phone.

But when it comes to property? You're waiting for a call back from a branch that closes at 5:30\. Your offer is being managed in a spreadsheet. Your tenancy renewal is stuck because someone forgot to send an email.

The infrastructure that powers how people find homes, move between them, and manage their biggest asset has barely changed in 30 years.

Nobody has built the definitive AI agent layer for real estate yet. That's what we're doing.

cinnamon.io is a platform of AI employees that handle the property transaction end to end.

Our first AI hire is already live with agencies across the UK.

About us

• Backed by Entrepreneurs First and top\-tier VCs (our first investor was early investor into Canva)


• Live with leading agencies across the UK with early US traction


• Based in Aldgate, London.

What you'll do

Own product surfaces end\-to\-end.

• Build and evolve an AI Native property platform used today by agencies across the country


• Build consumer facing products to help home renters, buyers and sellers interact better.

Build the systems behind them.

• Work across our Next.js / TypeScript application and Python / FastAPI services.


• Build LLM\-powered workflows, agents, RAG pipelines and data layers from scratch


• Work with tool calling and agent orchestration.


• Work with PostgreSQL, Redis, vector databases and other infrastructure required to make the product reliable at scale.

Own what you ship.

• Take features from customer problem to architecture to production.


• Debug production issues across frontend, backend and LLM systems.


• Own observability, performance and reliability rather than throwing problems over the wall.


• Make architectural decisions with incomplete information and move quickly.


• Talk directly to customers when that's the fastest way to understand the problem.


• Help set the technical bar and shape how the engineering team works as we grow.

You'll be a great fit if

• You're genuinely full\-stack. You're strongest in Python/FastAPI but equally comfortable in TypeScript/React/Next.js.


• You've built with LLMs in production. Not just demos. You've worked with orchestration, agents, RAG, streaming responses, evals, structured outputs or human\-in\-the\-loop systems used by 1000s of people in production.


• You have strong product and UX instincts. You care about trust and clarity in AI products and notice when an interface technically works but feels wrong.


• You can own ambiguous problems. You don't need a perfectly written spec. You talk to the user, work out what matters and make the call.


• You're good at debugging. You can trace problems through logs, application code, data and LLM behaviour rather than guessing.


• You're comfortable with data\-heavy products. Large datasets, search, dashboards, structured and unstructured information, performance optimisation.


• You've shipped end\-to\-end. From API design and data modelling through to a polished customer\-facing interface.


• You move fast. You know the difference between technical debt worth taking and shortcuts that will hurt us later.


• You want ownership. You're excited by being one of the people responsible for deciding how the product and engineering organisation should work.

We care more about what you've built, how you think and how quickly you learn.

Technical experience we're looking for

Core

• TypeScript / JavaScript


• React / Next.js


• Python / FastAPI


• PostgreSQL


• Production cloud infrastructure on GCP or AWS


• Building and operating production web applications

Strong signals

• LangGraph, Vercel AI SDK or similar agent / LLM frameworks


• RAG systems and vector databases such as pgvector or Pinecone


• LangSmith, Datadog, Sentry or similar observability tooling


• Tailwind CSS, ShadCN or similar frontend tooling


• Real\-time or streaming applications


• Experience with large datasets and natural\-language search


• Building products 0 to 1 or scaling an early\-stage product

Bonus points

• Previous founding engineer, early startup engineer or CTO experience


• You've built AI products used by real customers at meaningful scale


• WhatsApp Business API, Twilio or other messaging/telephony integrations


• Strong design or UX background


• Experience with voice AI, STT/TTS or real\-time conversational systems


• You've worked directly with customers rather than only through product managers


• You might want to found a company yourself one day

This role isn't for you if

• You want a predictable 9\-to\-5


• You'd rather work from a detailed backlog than own whole problems


• You want to specialise narrowly in one part of the stack


• You don't enjoy talking to users or understanding why they're struggling


• You want technical decisions to come from someone above you


• Five days a week in the office sounds exhausting rather than energising

How we work

We're an early\-stage startup and we work like one.

The pace is fast, the bar is high, and we're in the office together five days a week. Decisions get made quickly and you own your work. No committees, no waiting for permission.

We're rebuilding a $1T\+ industry and we don't think that happens on a 9\-to\-5\.

We're also having fun. The team is small, ambitious and genuinely enjoys building together. If that intensity sounds draining rather than energising, this probably isn't the right role.

What we offer

• £80K\-£110K base depending on experience


• Meaningful founding equity


• Real ownership over the product and technical direction


• Private health insurance


• Wellhub Gym/Wellness plan


• Dinners in the office


• Brand new MacBook

But the real offer is ownership. You'll help decide what we build, how we build it, and what the engineering team becomes as cinnamon grows.

Pay: £80,000\.00\-£110,000\.00 per year

Work Location: In person

This listing is from Indeed. View original listing ↗