Be a part of the next big thing

Do you thrive on tackling complex challenges? Are you passionate about creating impactful solutions that drive commerce forward? Do you believe in encouraging and elevating those around you?

About us

Kustom, formerly known as Klarna Checkout (KCO), is the Nordic market leader in digital checkout solutions. Today, we support over 24,000 merchants across more than 170 countries, providing a streamlined checkout experience. We offer localized solutions in 18 markets, tailored to specific languages, currencies, and payment methods. No matter where businesses operate, we deliver a checkout experience that meets the needs of both merchants and shoppers - driving growth globally. 🌍

The role

We are looking to hire a Frontend Engineer to join our development team. In this role, you will be responsible for designing and implementing user interfaces using modern JavaScript frameworks. You will work closely with our designers, product managers, and backend engineers to deliver seamless and engaging web applications that optimize user experience and drive conversion.

As a key member of our development team, you'll be at the forefront of crafting exceptional digital experiences. We're not just looking for someone to write code - we're seeking a creative problem-solver who can transform ideas into intuitive, cutting-edge interfaces for our users. Your expertise will help shape the future of our products, making complex flows feel effortless.

At Kustom, you'll have the opportunity to make a real impact on our users' daily interactions. If you're passionate about creating high-performance web applications and thrive on turning ambitious design concepts into reality, we want to hear from you.

Our engineering teams are based in Stockholm, where we prioritize in-person collaboration at our office to foster strong team dynamics.

Things you'll be doing

• Lead and architect complex frontend solutions using modern JavaScript frameworks and best practices. 
• Design and implement scalable component libraries and design systems that can be leveraged across multiple projects.
• Drive technical decisions and establish development standards for the team.
• Mentor junior developers and conduct code reviews to ensure code quality and knowledge sharing.
• Identify and resolve complex performance bottlenecks.
• Evaluate and implement new technologies that can improve development efficiency and product quality.
• Lead technical discussions and present architectural solutions to stakeholders.
• Champion best practices in frontend testing, accessibility, and security.
• Contribute to the company's technical vision and roadmap.

Skills and experience you'll need

• Bachelor’s degree in Computer Science, Engineering, or a related field.
• 7+ years of professional experience in frontend development.
• Deep expertise in JavaScript ES6+ and modern frameworks (preferably React).
• Strong understanding of HTML5, CSS3, and responsive design principles.
• Experience with state management libraries like Redux or Vuex.
• Familiarity with RESTful APIs and asynchronous request handling.
• Knowledge of modern authorization mechanisms, such as JSON Web Token.
• Proficient understanding of code versioning tools, such as Git.
• Experience with frontend testing frameworks like Playwright, Jest, Mocha, or Cypress.
• Strong problem-solving skills and attention to detail.
• Strong communication skills and ability to work in a dynamic startup environment. 

We believe you'll thrive in this role if you have

• Experience with server-side rendering and Next.js.
• Familiarity with TypeScript.
• Knowledge of web performance optimization techniques.
• Strong understanding of User Experience (UX) principles and best practices.
• Experience with A/B testing and conversion rate optimization (CRO).
• Experience with Agile/Scrum development methodologies.

Benefits 

• Robust pension plan with national and occupational components
• Excellent health insurance coverage, including long-term illness protection and salary exchange options
• Annual wellness allowance of 3,000 SEK to invest in your health and fitness
• Extra day off when major holidays (e.g., Christmas Eve, New Year's Eve) fall on weekends
• Continuous learning opportunities and professional development support

A place to grow

At Kustom, you won’t just be another face in the crowd. This is a place where we elevate each other and celebrate success as a team. We believe in our ability to create excellence — and have fun doing it!

We know we set high expectations, but we also know that the road to success isn’t a straight line. We support and encourage each other to try, to fail, to try again. Because that’s how we grow, individually and together.

Does this sound like the place for you?

About your application

• Please apply in English. At Kustom, we welcome everyone! We don’t care where you’re from, whom you love, or what kind of food is your favorite (unless we’re celebrating together, then we’ll need to know!). We believe in inclusivity for all.
  
• Given the above, we treat all candidates the same! That’s why we have this awesome recruitment tool to keep track of all the amazing talents that apply - so please; apply through the system and we’ll make sure to keep you updated along the recruitment process. Please note that we can’t keep track of CVs or similar documents sent via email.
• We value your privacy! When you apply, we'll handle your data with care. Want to know more about how we use your information? Check out our FAQs at the bottom of the jobs page - we've got all the details there for you!