workable

Experience Engineer (FTC)

Callsign

London, GBR

Contract, Temporary

Mid

Hybrid

Discovered 2 weeks ago

TypeScriptReactNodeJavaGitLab CI/CDHelm

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Full Job Posting

Product & UX

Own features end-to-end, from ambiguous requirements to shipped experience: fills design gaps with defensible decisions and delivers a coherent flow rather than a set of components

Contribute actively in refinement: challenge requirements with evidence, propose simpler alternatives, and bring product ideas of your own

Know the outcome each feature serves, instruments what they ship so that outcome is measurable, and checks whether it landed (usage, feedback, demo performance) rather than stopping at merge

Understand the domain the product lives in (fraud, identity, authentication, and the client's operational world) well enough so that gap-filling decisions reflect

Frontend craft

Implement non-trivial components and async data flows

Diagnose and fix performance and accessibility issues rather than merely detecting them

Handle secrets/config surfaces safely

Full-stack

Ship features that span frontend, backend service and configuration

Debug across the boundary to root cause

Significant changes start as a written design others can review, rather than as code

Quality

Design the test approach for your features (what gets unit, component and e2e coverage, and why)

Keep regression suites healthy in your area; e2e failures you own get fixed rather than retried

Platform

Land toolchain and pipeline improvements (build config, CI automation, test infra, dependency upgrades) beyond your immediate feature work.

Key Responsibilities

Ship across the stack: TypeScript/React frontends, Node services (with some Java in the portal estate), API contracts, GitLab CI/CD, and deployment via Helm, GitOps and Terraform.
Treat the frontend craft triad - accessibility, performance, security - as engineering, with expectations that rise as you grow.
Build with AI as a core part of your workflow, with the verification discipline a regulated product demands.
Learn the domain deliberately: fraud, identity, authentication, and our clients' operational world, because product decisions made without it are guesses.
Write meaningful tests for everything you ship.

Required Skills & Experience

A must:
Solid JavaScript/TypeScript and React.
Comfort somewhere beyond the frontend: an API, a service, or infrastructure.
System design and architecture, designing features that span frontend, service and configuration.
Evidence of AI-native working with stated verification.
A testing instinct: you can design a test approach and defend it.
Would be great:
Product judgement demonstrable from your history: UX decisions made and defended without a design spec.
Ownership of a surface or programme through its worst weeks, at any scale.
Nice to have:
Java in production; design systems or component library work; SDK or library engineering; data visualisation
Experience in regulated industries (fintech, identity, payments).

Benefits

Pension scheme with Scottish Widows
Private medical cover with Vitality
Life assurance (4x base salary)
Personal Learning & Development Budget
Cycle to Work Scheme
Company Family Leave
25 days annual leave plus Callsign Bank Holiday
Employee Volunteering Program

Requirements

A must:
Solid JavaScript/TypeScript and React.
Comfort somewhere beyond the frontend: an API, a service, or infrastructure.
System design and architecture, designing features that span frontend, service and configuration.
Evidence of AI-native working with stated verification.
A testing instinct: you can design a test approach and defend it.
Would be great:
Product judgement demonstrable from your history: UX decisions made and defended without a design spec.
Ownership of a surface or programme through its worst weeks, at any scale.
Nice to have:
Java in production; design systems or component library work; SDK or library engineering; data visualisation
Experience in regulated industries (fintech, identity, payments).

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