AI Engineer (Catalyst) in London

About Us

Fifth Dimension is the most prominent AI company in real estate in the world, bringing vibe working to document-heavy industries. We work with real estate businesses in the US, EU and APAC, automating complex tasks, extracting valuable insights from documents, and empowering professionals to focus on high-impact work. Our AI workspace transforms how large investment managers and developers handle leases, development documents, and investment decisions. We’re a London, New York and Singapore based startup with an ample runway, backed by Tier 1 European and American investors. Our founders, Johnny Morris and Dr. Kate Jarvis bring a powerful blend of expertise: Johnny has 17+ years applying data and analytics to Real Estate, while Kate holds a Stanford PhD and 12 years of executive experience across Silicon Valley and London startups. At Fifth Dimension, we’re demanding yet encouraging, valuing experimentation and kind challenges. Our company values, Own It, Ship It, and Don’t Be Boring, drive us to deliver exceptional results while fostering a culture of innovation and continuous improvement.

The Challenge

It’s 9 AM on a Monday. You’ve already got a couple of AI-generated PRs from the weekend open for review – experiments you kicked off with Claude Code on Friday that ran overnight. By 10:30, the reviews are in and you’re iterating. By lunch, one feature is in staging with tests. After a quick review with a staff engineer who raises an edge case you hadn’t considered, you ship v2 by 3 PM. By the end of day, real customers are using it—and you’re already looking at the eval results to figure out what v3 needs. On Tuesday, you sit with one of our Solutions Engineers and a Customer Success Manager to understand why a major asset manager’s lease analysis is hitting a wall. By Wednesday, you’re pairing with a principal engineer to redesign the approach – they bring deep knowledge of how commercial real estate documents actually work, you bring the speed to prototype three different solutions in Claude Code before lunch. You run evals against your test suite, pick the winner, and ship it. On Thursday, you’re with the PM refining the intelligence platform’s UI based on what the usage data told you. On Friday, you demo everything you shipped that week. It’s more than most teams ship in a sprint. That’s a normal week here. And next month, you might be doing it from our New York office, or from Singapore.

About You

You’re an AI-first engineer. While others debate whether AI tools are ready, you’ve been shipping with them for months, maybe years. Claude Code and Codex aren’t novelties to you; they’re how you work. You’re outcome-obsessed and customer-obsessed: you don’t just build features, you solve problems for real people and measure whether it actually worked. You’ve already figured out that the combination of strong fundamentals, AI-augmented development, and relentless focus on customer outcomes lets you move at a pace that surprises people. You might be early in your career by the calendar, but not in output. You’ve built and shipped things, side projects, open-source contributions, startup experiments, freelance work, that demonstrate you can go from idea to production. You care about quality, but you know that shipping fast and measuring is how you learn what quality actually means for users. You’re not intimidated by working alongside staff and principal-level engineers. You know you have things to learn from them – deep architectural thinking, domain expertise, battle scars from systems at scale. But you also know you have something to teach: how to wield AI tools to ship 10x faster without cutting corners. That exchange excites you. You experiment compulsively. You measure obsessively. You learn fast and apply what you’ve learned immediately. You’d rather ship something imperfect and iterate than perfect something nobody’s using.

Your Impact

Reporting to our CTO Chen, you’ll be our first early career AI engineering hire—and that means you’ll help define what AI-first engineering looks like at 5D. You’ll work alongside staff and principal-level engineers who’ll stretch your architectural and domain thinking, while you push the team’s velocity and AI tooling practices forward. You’ll own real features end-to-end, shipping to enterprise customers.

Day to Day

• Ship features to production multiple times a day, using Claude Code, Codex and AI-augmented workflows as your primary development approach.
• Own features end-to-end: from understanding the customer problem, through implementation, to deployment and measuring impact.
• Build and evolve our AI intelligence platform—from agentic workflows and evaluation infrastructure to the UI/UX that puts AI capabilities in customers’ hands.
• Experiment rapidly—prototype approaches, measure results against our evaluation framework, learn from the data, and iterate.
• Pair with staff and principal engineers who bring deep domain and architectural expertise, while showing them new ways to leverage AI tooling for speed and quality.
• Collaborate closely with Product Managers, Customer Success Managers, and Solutions Engineers to stay rooted in what customers actually need.
• Contribute to our engineering culture by sharing what you learn about AI-first development workflows, prompting techniques, and tooling.
• Write code that’s clear, tested, and maintainable—speed without quality isn’t speed, it’s debt.

Our Values and Engineering Culture

• Product‑Minded Engineering: Understanding the “why” behind features and using technical expertise to inform product decisions.
• Intellectual Honesty: Backing discussions with data and acknowledging knowledge gaps.
• Effective Time Management: Setting clear timeboxes and abandoning approaches that aren’t working.
• Clear Communication: Writing self‑documenting code and providing detailed explanations.
• Innovation Mindset: Forming well‑reasoned opinions backed by data and continuously learning.
• Personal Growth: Supporting your development through challenging work and opportunities to expand your expertise.
• Having Fun: We’re building something extraordinary across three of the world’s most exciting cities. We take the work seriously, not ourselves.

What We’re Looking For

• Demonstrable experience shipping software—personal projects, open source, freelance, startup, or professional. The context matters less than the output.
• Fluency with AI coding tools (Claude Code, Codex) as part of your daily workflow, not as an occasional novelty.
• Strong programming fundamentals, particularly in Python and TypeScript—but we welcome experience in other languages and architectural paradigms too. You should be able to read, reason about, and debug code that AI helped you write.
• A portfolio or body of work that shows velocity and quality: things you’ve built, shipped, and ideally that people have used.
• Comfort with rapid experimentation: you prototype fast, measure outcomes, and aren’t precious about throwing things away.
• Intellectual curiosity and honesty—you dig into problems, share what you find (including failures), and ask for help when you need it.
• Clear communication: you can explain what you built, why, and what you’d do differently.
• Ambition and resilience—we’re tackling hard problems at the intersection of AI and real estate, and you want to grow with us.

Nice To Have (But Not Required)

• Experience contributing to open-source projects.
• Familiarity with cloud platforms (GCP preferred) or infrastructure tooling.
• Past exposure to real estate, law, or finance domains.
• Experience building or fine‑tuning with LLM APIs (Anthropic, OpenAI, etc.).
• A blog, Twitter/X presence, or community contributions that show how you think about AI-first development.

Why This Role Is Different

Most early career roles put you in a box: fix bugs, write tests, shadow seniors for six months before touching anything real. This isn’t that. You’ll own real features from day one, shipping to enterprise customers across the US, EU, and APAC. The guardrails are the staff and principal engineers around you and a culture that values measurement over ego—not a months‑long onboarding gauntlet. You’ll be surrounded by staff and principal-level engineers who’ve built systems at scale, know the commercial real estate domain deeply, and will challenge your thinking in ways that make you better. In return, you’ll challenge how fast they think things can be built. That two‑way exchange is exactly what we’re optimising for. There’s also the opportunity to travel between our London, New York, and Singapore offices—three epicentres of global real estate. It’s not for everyone, but if you’re excited by the idea of working across cultures and cities, it’s a genuinely unique part of what we offer.

What We Offer You

Up to £120,000 (London/Singapore) / $200,000 (New York) + meaningful equity on a standard vesting schedule. Our benefits are localised to your city—designed so you don’t have to worry about living your life in a big, expensive, exciting place. From tailored support for life’s challenges to enhanced parental leave, a well‑being budget, and an annual training budget—we want you focused on doing the best work of your career, not stressing about the rest.

The Process

Submit your CV, along with answers to the handful of questions we ask of every candidate. An initial call to explore fit. A live task and competency interview. An on‑site half‑day including a product building workshop and culture fit conversations with people across the business, including our founders. Alternatively, we offer a paid‑for one‑week trial for candidates who are available for the setup.