Senior Frontend Developer

Tantilium; Greater London; Hybrid; GBP 70,000 - 110,000; Full time

Job summary

Tantilium is building a web-based interface for deploying and observing Kubernetes workloads. You will own the frontend experience from design to production, shaping how the control plane feels in the browser, with Next.js, React, TypeScript and Tailwind.

As part of a small team, you’ll turn operational data into readable screens, ensure accessibility, and keep the app fast as clusters grow. You’ll collaborate with design and backend services over REST and WebSockets to ship reliable features.

Qualifications

• Several years building production web applications with React and TypeScript.
• Experience with Next.js including server rendering and routing.
• Strong CSS and responsive layouts; Tailwind preferred.
• Knowledge of WCAG accessibility testing.
• Experience optimizing performance for large clusters.

Responsibilities

• Build and ship features end to end from rough design to production.
• Turn dense data such as pods, rollouts, metrics into screens people can read at a glance.
• Keep the app fast as it grows: measure, profile and fix what's slow.
• Make sure keyboard and screen-reader users can do everything everyone else can.
• Work with design on a shared component library so new pages look and behave consistently.
• Review code, pair with other engineers and help newer teammates find their feet.
• Write tests where they earn their keep, and keep the build and CI quick.

Skills

React

TypeScript

Next.js

Tailwind CSS

CSS

Accessibility (WCAG)

REST APIs

WebSockets

Pair programming

Code review

Tools

Playwright

Cypress

Job description

Own the interface platform teams use every day to deploy, watch and fix their workloads. You'll shape how a complex Kubernetes control plane feels simple in the browser.

Tantilium Cloud Runner puts cluster management, deployments, observability, cost and security in one web app. Most of the heavy lifting happens behind an API, but people judge the product by what they see: a rollout they can follow, a log view that loads quickly, an incident page that tells them what to do next.

You'll be one of a small group of engineers responsible for that experience. The app is built with Next.js, React, TypeScript and Tailwind CSS, and talks to a set of Go services over REST and WebSockets. You'll have a real say in how it grows: component patterns, data fetching, performance budgets and the accessibility bar we hold ourselves to.

Responsibilities

• Build and ship features end to end, from a rough design to production, including the API conversations that come with them
• Turn dense operational data such as pods, rollouts, metrics and traces into screens people can read at a glance
• Keep the app fast as it grows: measure, profile and fix what's slow, especially for customers with large clusters
• Make sure keyboard and screen-reader users can do everything everyone else can
• Work with design on a shared component library so new pages look and behave consistently
• Review code, pair with other engineers and help newer teammates find their feet
• Write tests where they earn their keep, and keep the build and CI quick

Requirements

• Several years building production web applications, with a good stretch of that spent in React and TypeScript
• Hands-on experience with Next.js or a similar framework, including server rendering and routing
• Strong CSS skills. You can build a responsive layout from scratch, and utility-first CSS like Tailwind doesn't put you off
• A working knowledge of web accessibility (WCAG) and how to test for it
• Experience making a slow app fast, and the numbers to show for it
• Comfort working with REST APIs and live data over WebSockets or server-sent events
• Clear written communication. We're remote, so a lot of decisions get made in pull requests and short design docs

Nice to have

• You've built dashboards, developer tools or other data-heavy products before
• Some time with Kubernetes, even if it's only your own side projects
• Experience with charting libraries such as Recharts or D3
• End-to-end testing with Playwright or Cypress