Staff AI Designer in London

Fin is the AI Customer Agent company on a mission to help businesses provide perfect customer experiences. Our AI Agent Fin is the highest-performing AI Customer Agent on the market today, enabling businesses to deliver impeccable, always-on customer support across the customer journey – from service, to sales, to ecommerce. Powered by our own AI models, Fin resolves complex customer issues end-to-end across every channel, with minimal set-up and integration. Fin can also be combined with our natively integrated help desk for one single system that is designed to meet the needs of modern day support teams. Founded in 2011, Fin became one of the fastest growing companies and remains one of the largest private software companies in the world with nearly 30,000 global businesses using our products to transform their customer support. Driven by our core values, we push boundaries, build with speed and intensity, and relentlessly deliver incredible value to our customers.

Role Overview

We’re looking for a Staff AI Product Designer to shape what our AI does, how it behaves, and how it fits into real user workflows. This role sits at the intersection of product, design, and machine learning—turning emerging capabilities into reliable, high-quality user experiences. You’ll design systems: behaviours, decisions, orchestration, and end‑to‑end experiences powered by AI. This is not a traditional product design role. You’ll go beyond interface design to define how AI systems behave, operate, and deliver value in the real world.

• Define AI capabilities (the “what and why”)
• Identify and pattern match high‑value opportunities for AI across the product
• Define what AI should do—and just as importantly, what it should not do, making hard or unpopular calls when needed
• Set clear boundaries for autonomy vs human control
• Design AI behaviour, orchestration, and system logic
• Architect AI‑driven workflows and agentic systems that operate across real‑world scenarios and over time, including multi‑step and agent‑to‑agent interactions
• Establish decision frameworks: when systems should act, ask, elevate, or defer
• Design for uncertainty, failures, and edge cases as core system behaviour
• Develop and apply design principles and heuristics to shape how AI systems behave and make decisions
• Ensure systems remain coherent and predictable, even as complexity scales
• Shape human + AI workflows and end‑to‑end experience
• Design experiences for users who are increasingly managing AI systems and agents
• Design how AI integrates into real user workflows, not just isolated interactions
• Define the role of the human in the loop: where users guide, review, or override
• Ensure users can understand, trust, and recover from system failures
• Partner with product designers to continuously shape and adapt the product experience as underlying systems evolve

Define quality, evaluation, and reliability

• Define what “good” looks like (e.g., trust, accuracy, effort reduction, and whether outputs are structured and usable in context)
• Design evaluation scenarios and feedback loops
• Analyse outputs to identify failure modes and system weaknesses
• Design for reliability at the system level, preventing agentic breakdowns

How You’ll Work

• Shape direction from the earliest stages of zero‑to‑one problems
• Influence across teams without formal authority
• Operate in a highly autonomous, fast‑moving environment with evolving constraints
• Lead ambiguous, in‑flight work—making calls on when to adapt the product vs. push on system improvements as things evolve
• Act as a bridge between AI research, technical capabilities, and user needs
• Collaborate deeply with ML scientists, PMs, and product designers
• Prototype and run focused experiments that isolate variables and generate clear insights
• Stay close to system behaviour by regularly reviewing outputs and raising the bar on quality

What We’re Looking For

• Strong product judgment—you consistently make high‑quality calls on what to build and why
• Ability to influence without authority
• Experience working on zero‑to‑one products and comfort operating through ambiguity and rapid change
• Deep understanding of LLMs and their limitations, along with a grounding in traditional ML approaches and when to use them instead
• Experience defining design principles, heuristics, or evaluation criteria for AI systems
• High standards for quality, with a track record of identifying where AI systems break down in real‑world use
• A scientific mindset—you can design experiments that isolate variables and produce meaningful insights
• Systems thinker: you’re happier designing behaviours and flows than polishing interfaces
• We’re open to non‑traditional backgrounds (e.g. product managers, engineers, or others) if you have strong product sense and a track record of representing user needs in technical systems

What This Role Is Not

• You will not be training models or building ML infrastructure
• You will not be responsible for backend architecture or performance optimisation
• You will only occasionally design UI—this is not the focus of the role

You will influence all of these—but your primary responsibility is defining what should be built, how it should behave, and how it performs in the real world.

Why This Role Is Compelling

You’ll join a mature AI discipline operating at the frontier. Fin already has an established AI Design team and strong cross‑functional understanding of this role, so you can focus on building rather than justifying your value. You won’t be “adding AI to a product.” The quality of our AI is the quality of our product. This is a technical, hands‑on role where you have the satisfaction of working with tight feedback loops. You’ll shape product direction, not just execution. You’ll operate upstream in a high‑autonomy environment with real ownership over outcomes.

Benefits

We are a well treated bunch, with awesome benefits! If there’s something important to you that’s not on this list, talk to us!

• Competitive salary and equity in a fast‑growing start‑up
• We serve lunch every weekday, plus a variety of snack foods and a fully stocked kitchen
• Regular compensation reviews – we reward great work!
• Unlimited access to Claude Code and best‑in‑class AI tools; experimentation & building is encouraged & celebrated.
• Pension scheme & match up to 4%
• Peace of mind with life assurance, as well as comprehensive health and dental insurance for you and your dependents
• Flexible paid time off policy
• Paid maternity leave, as well as 6 weeks paternity leave for fathers, to let you spend valuable time with your loved ones
• If you’re cycling, we’ve got you covered on the Cycle‑to‑Work Scheme. With secure bike storage too
• MacBooks are our standard, but we also offer Windows for certain roles when needed.