Junior Full-stack Developer

at Mercive Are you early in your career as a developer and eager to take ownership of what you build? Do you learn fast, and are tools like Claude Code or Cursor already a natural part of how you work? Then you might be the person we're looking for at our office in the center of Copenhagen. Mercive is a fast-growing Shopify e-commerce agency based in Copenhagen. We're the right match if you want to join a team that pushes boundaries and solves real business problems through design, technology, and strategy. We believe AI is fundamentally changing how software gets built, and we're putting it at the core of how we work, not as a gimmick, but as a genuine multiplier for quality, speed, and what's even possible to deliver. We're looking for builders with an entrepreneurial mindset: people who take initiative, own outcomes, and hold themselves accountable without waiting to be told.

The Role You'll work on e-commerce projects where AI is a core part of how we build, whether that's AI-assisted coding to move faster, building AI-powered features into client projects, or automating away repetitive work. We expect you to already work actively with tools like Claude Code, Cursor or similar, whether in a job, in your studies or on your own projects. Here you'll learn to use them well on real client work, together with experienced developers. Shopify is our main focus, and you'll contribute to solutions across the Shopify ecosystem, such as: Loyalty programs and subscription programs

Custom apps for brand and product launches

Automations and integrations with the other systems our clients rely on

Internal optimization tools for clients and for our own team

Speed and performance optimization of webshops

Platform migrations to Shopify and new storefronts

The tech stack varies by project: native Shopify work in Liquid, HTML, and CSS, headless builds in Remix.js / Next.js, and backend services and APIs in Node.js on Google Cloud. You'll work on these as part of larger projects, with support from senior developers along the way. This is a fast-paced environment where you'll learn a lot, and where the people who take ownership and run with things go furthest.

Responsibilities Build features, storefronts and improvements on Shopify projects, both in native Shopify and in headless builds with Remix.js / Next.js

Use AI-assisted development tools like Claude Code and Cursor as part of your daily workflow, and review and understand the code they produce

Contribute to AI-powered features in client projects and help automate repetitive work

Work on backend services, APIs and Shopify apps with guidance from senior developers

Write code that meets our internal standards for style, maintainability, security, and best practices

Work closely with the project management team and other developers to plan and deliver tasks

Ask questions, take feedback, and grow your skills across both frontend and backend

Qualifications An entrepreneurial mindset: you take initiative, own your tasks, and hold yourself accountable

Hands-on experience working actively with AI-assisted development tools such as Claude Code, Cursor or similar, from work, studies or your own projects

Up to 2 years of professional experience, or a relevant education and projects that show what you can build

Experience with JavaScript and a modern framework such as React, Next.js or Remix.js

A solid understanding of semantic HTML, CSS, and core JavaScript concepts

Basic knowledge of Node.js and building APIs

Experience using Git

Interest in e-commerce, and experience with Shopify is a plus

Positive, solution-oriented mindset, with strong organizational skills

Benefits Daily lunch at Restaurant Lalala

Coffee, soda & snacks in the office

Friday bars & fun events

Office located in central Copenhagen

If you can see yourself being a part of Mercive, please send us your CV and a description of why you are interested in this role. Your application must include specific examples of what you have built, with links where possible. Applications without them won't be considered. You need to be located close to Copenhagen to be considered for this job.