Senior Frontend Engineer (m/f)

Berlin, Germany · Engineering and Software Development


About SumUp

The people of SumUp have brought the best way to accept card payments to 15 countries so far, but we won’t stop there. Headquartered in London, SumUp's major offices are in Berlin, Sofia and São Paulo. The Berlin office alone comprises more than 100 people from 24 countries. We recently launched a brand new contactless device, which makes paying by card easier than ever before.

Why work with us?

SumUp could be interesting for you as an engineer in part because we cover so many platforms: we have physical hardware (made right here in Berlin), our own proprietary payment processing platform, mobile apps on iOS and Android, SDKs and APIs supporting third-party integration, and of course (the main star, in this team's humble opinion) a merchant-facing web app.

What we're looking for

A web developer with Javascript expertise, who will be able to contribute to and benefit from our team's ambition to improve our app, our code, and our technical abilities every day.

To us, fullstack means you are comfortable working with the machine on all the levels most meaningful for web today: you're familiar with Node, you're comfortable with Unix as it relates to your work, you're familiar with developing frontend apps in JavaScript, as well as making them look decent with HTML/(S)CSS based on specs provided by designers.

This position is frontend heavy in its day-to-day responsibilities, but requires a thorough knowledge of the full stack to operate efficiently.

You'll fit in perfectly to our team if:

Our tech stack and projects

Dashboard: A modern Angular 1.6 application helping merchants keep track of their revenue and manage their accounts. Our core features include sales analytics, a transaction overview, and account management. We've started writing new components in React, and plan to open source a React UI library that bridges our merchant-facing apps and our website.

Our codebase uses a modern component approach and pure services supported by Jasmine unit tests. Apart from that, we heavily use libraries like Moment.js and d3, and rely on Webpack for our build and npm scripts for our dev tasks. Naturally, our codebase is in ES6.

Website: Our website uses Jekyll and is served by a Node server (using Koa, the spiritual successor to Express) that's largely powered by a headless CMS (which we don't maintain, win!).

Right now we're migrating the website to render from isomorphic react components, so our marketing and sales teams can build their own pages entirely from components, without a developer.

On our roadmap: We're always looking at what's happening in the ever-changing web development space. We're currently investigating how we can make our web app offline-first, switching our test runner from Karma to Jest, and implementing a library-agnostic caching solution to further decouple our code from the framework.

The backend that powers SumUp is a constellation of microservices, mostly written in Ruby but with an increasing number powered by Node. If you're interested in the nitty gritty of the complex domain of card payments, there's space for you to expand your responsibilities to the backend.

Your impact at SumUp

You'll shape some of the core experiences of our merchants: from their first impression on our website, to the web-based features that make them loyal to our platform.

In the first few weeks, you'll dive into the code and learn how to create clean, composable components in our codebase. You'll use this knowledge to start developing and refining features. You'll learn how we write tests, how we manage application state, and how we keep performance tip-top. You'll also pitch in on our Jekyll site to enable sales and marketing to reach hundreds of thousands of visitors every month.

In the first three months, you'll develop major features that impact our merchant base. You'll work closely with product and design departments to build features that are maintainable, usable, and beautiful. You'll help us re-think problems we've solved before in a different way as requirements evolve. You'll also leave your mark on the SumUp web experience by conducting A/B tests on the Jeykll site as well as during onboarding in the web app.

In one year, you'll have a wealth of knowledge about our complex problem domain, as well as its implications in the interface and in the backend – and how to manage it in a clean way. You'll have launched numerous features on the Dashboard, as well as contributed to side projects and initiatives that gave you an opportunity to diversify your skills and learn something new.


Required qualifications:

A strong candidate will also have:


More reasons to work at SumUp

Apply now!

We're looking forward to meeting our next teammate! You'll be asked to provide the following information when you apply:

You can also choose whether to include a CV, a link to your Xing/LinkedIn, a link to your github, tech blog, or portfolio – whatever you think will give us the complete picture!

If you want to know what it’s like to work at SumUp check our careers page:

If there's something you'd like to ask, feel free to get in touch:

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