The role

You'll build and own the backend systems Letly runs on — the software behind every viewing, tenancy, certificate, rent payment and repair. These are systems where correctness, reliability and scale are non-negotiable: real people's money, homes and legal exposure are on the line.

This is one role hiring at every level, junior to staff — we level on the scope you own, not years served. At junior you ship features inside services others own, with review, mentoring and real production responsibility from the first month — the fastest engineers here ask early and close the loop quickest. At mid you own features and services end-to-end. At senior you own systems others build on — you make the architecture calls, set the patterns, and raise the bar around you. At staff you own the technical direction of a domain: you decide what gets built and how, you unblock other engineers, and you answer for how those systems behave under load.

What you'll work on

• Money movement. Rent, deposits and payouts through pooled client-money accounts — idempotent processing, split-settlement, exactly-once across service and bank boundaries.

• Reconciliation & bookings. A penny-accurate, self-healing ledger reconciling bank activity across thousands of tenancies; contended scheduling — viewings, certs, photography, maintenance against finite slots and vendor availability.

• Event-driven consistency. Services coordinating over Pub/Sub — sagas across offer → contract → tenancy → payment with no distributed transaction to lean on. LLM tool calling, deterministic API calls, and other intra- and inter-service communications all running across the same coordination system.

• AI harnesses in production. Deploying agentic AI into real-world operational settings — acting on real money, tenancies and legal exposure, with the guardrails, observability and correctness that demands. Non-deterministic LLM working within compliant, secure deterministic software.

Our stack

We build on NestJS + TypeScript on GCP / GKE, with MongoDB, Redis and GCP Pub/Sub.

You don't need to arrive fluent in it. We hire strong backend engineers who've built production systems with any robust framework — Java/Spring Boot, Go, Kotlin, C#/.NET, Python (Django/FastAPI) or Ruby on Rails — and can ramp into TypeScript fast. We care that you've built and operated real backends, not which language you did it in.

How we build

Small, well-factored services. TDD and DDD as defaults. Trunk-based CI/CD — you ship to production and own it, with tests, observability and clean rollbacks. Lean frameworks, readable code, and we move fast because the tests and boundaries let us.

What we're looking for

• 0–2 years building production backend systems for junior, 3+ for mid, 6+ for senior and staff — we level on the scope you've owned; for junior, serious internships or shipped side projects count.

• Fluency in at least one backend language and framework, and the range to reason about system design — services, data models, APIs, failure modes.

• Strong fundamentals: concurrency, HTTP and API design, data modelling (document or relational), and what actually happens when a call fails.

• You treat tests as part of shipping, and you can read a large codebase you didn't write.

• AI-Native engineer: you use AI across all layers of your work and utilise models expertly while understanding LLM failure modes and patterns.

• Junior: you've shipped code real users depended on — an internship, a placement or a substantial side project counts.

• Mid: you've owned a service or a substantial feature end-to-end — scoped it, shipped it to production, and owned it after launch.

• Senior: real distributed-systems experience at production scale and a track record of designing systems other engineers built on.

• Staff: you've set technical direction across several services or teams, and you're the person others escalate to when it's hard.

Nice to have

• MongoDB and GCP/GKE, plus containerised cloud deployment (Docker, Kubernetes on GCP or AWS).

• Event-driven architecture and message brokers (Pub/Sub, Kafka).

• Payments, ledgers, reconciliation, or another regulated, high-trust domain where being wrong costs money.

• A computer-science or other technical degree, or a track record that makes one irrelevant.

Who does well here

• You're precise about correctness — these systems move money; "mostly right" fails.

• You own the outcome, not the ticket — start to production, without being chased.

• You make the next engineer faster — clear code, clear reasoning.

• You want the hard problems — you get real ones early, and you raise the standard around you.

Why apply

Letly is the AI-Native operating company built for the home. We believe the home will be autonomously run by AI and we're building the software that will run all rental properties end-to-end, starting with London (the world's 2nd largest rental city).

The backend at Letly is technically difficult on purpose: messy operational reality that doesn't fit clean schemas; money moving across financial rails where being wrong is not an option; high throughput across thousands of concurrent journeys; and a large surface serving many user types with different needs, permissions and trust levels. Every Letly customer is served by the system you build, and the work compounds — every service and primitive keeps producing value after you ship it. Whatever your level, you work on distributed systems and money movement now, not in three years.

We've raised a $4m pre-seed from investors who've built the financial and operational infrastructure that moves billions and serves millions. They backed us because the home is the largest consumer asset where that infrastructure hasn't been built yet. You'll get competitive base pay, meaningful equity, and a small, high-agency team rebuilding an industry and growing at >100% month-over-month. We're hiring to facilitate this aggressive growth.

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