Senior Frontend Engineer (Conversational & General User Interface)

Farther; York and North Yorkshire; On-site; GBP 90,000 - 120,000; Full time

Benefits offered by this job

Opportunity to work with a talented团队

Job summary

Farther is seeking a senior frontend engineer to shape the system that defines what a screen can be and its guardrails for unexpected model outputs.

You will help build the framework powering the AI assistant across React, TypeScript, and Python, turning model results into validated, submittable interfaces. You’ll own end-to-end delivery, mentor peers, and work with backend contracts to drive rapid, robust product growth.

Qualifications

• 6+ years building production web applications with frontend focus.
• Experience with agentic systems, LLMs, tool calling, and streaming responses.
• Strong typing and modular frontend patterns; end-to-end ownership.

Responsibilities

• Design the system that defines what a screen can be and guardrails for unforeseen model outputs.
• Contribute to both the framework and the AI assistant itself.
• Prototype, productionize, and deliver the assistant experience across surfaces.
• Build the underlying framework for declarative UI contracts and cross-team integration.
• Negotiate and version wire contracts with backend teams; enforce with tests.
• Mentor engineers and uplift engineering quality in reviews.

Skills

React

TypeScript

Python

TanStack Query

React-hook-form

Zod

Tailwind

CSS

Testing Library

ESLint

Prettier

GitHub Actions

Tools

AWS

Vercel

DynamoDB

CloudWatch

Job description

• Farther’s AI assistant answers advisor questions and drives the product on their behalf — navigating, opening workflows, and more
• This role continues and deepens the interaction between the assistant and our traditional UI platform. Next, it composes the interface itself
• You will contribute to both the framework that makes that possible and the assistant itself
• You are not designing screens, you are designing the system that decides what a screen can be, and the guardrails for the moment it is handed something nobody anticipated
• Deliver the assistant experience, prototype → production — the surface advisors reach for, and the thing every other item on this list exists to make possible
• Build the framework underneath it, so any Farther surface can declare what the agent can do and what it can see in a few lines
• Design the renderer that turns a model’s output into a real, validated, submittable interface, extensible so a new kind of input is additive and never a refactor
• Negotiate and version the wire contract with the agent backend team, and hold both sides to it with tests
• Treat developer experience as a first-class deliverable — design the API, document it, and judge it by how many teams build on it without asking you for help
• Mentor the engineers coming up behind you and set the quality bar in review
• Technical Stack
  React
• TypeScript
• Python
  TanStack Query
• React-hook-form
• Zod
  Styling — Tailwind and CSS
  UI modules built and deployed independently, then assembled into one application
  Testing Library
• ESLint
• Prettier
• GitHub Actions CI

Benefits

• Opportunity to work with a talented team of professionals.
• Drive the success of a venture-backed, rapidly growing firm

Comfortable context-switching across multiple concurrent workstreamsFluent in an AI-assisted development loop — building with Claude Code, shipping through Git-based PRs and automated reviewDistributed systems fundamentals — timeouts, retries, idempotency, failure isolationGenuine product instincts — you care about the user experience, and raise ambiguity as a decision rather than absorbing it as a guessComposition over configuration; modular, scalable frontend patterns are how you think by defaultStrong knowledge-sharing / documentation habit6+ years building production web applications, including time somewhere the frontend was the productProduction experience with LLMs — agentic systems, tool calling, streaming responses, conversational interfaces — and a point of view on what an interface owes a user when the model is slow, wrong, or halfway through an answerExpert-level frontend engineering, where strict typing is how you already workEnd-to-end ownership and a track record of meeting deadlinesUsed or extended a framework for agent-to-UI communication, and can say precisely where it stopped being enoughBuilt and versioned a component library other teams depended on, and know what a breaking change costs once they have all imported itAWS fluency — Lambda, API Gateway, DynamoDB, CloudWatchTurned LLMs on how your own team builds: codegen, large-scale migrations, spec-to-code pipelinesEngineering platform or internal tooling — Vercel, an internal PaaS, or the developer platform at your last companyWealth management, financial services, or analytics products dense with numbers people act on — including the craft that keeps them fast: profiling, bundle size, render performance