Job Title: Full-Stack Developer

Location: Copenhagen

Job Type: Full-time

Start Date: As soon as possible

About Numina 🔮

Founded in 2024, we're building the next generation of AI-first core accounting software. Our dream is to make it much easier to run a small business with our self-driving bookkeeping solution.

We are live with our Private Beta, the first 20 companies are onboarded, and our waitlist is 250+ companies long. Having raised a pre-seed round from top-tier investors, we're ready to accelerate and migrate more businesses to Numina.

While our team is small, we come with experience from building recognized scale-ups like Pleo and Weld. You'll work directly with the co-founders, helping us build the technical foundation of Numina from the ground up.

The Role 👀

As our first dedicated Full-Stack Developer, you won't just be joining a team; you'll be a foundational pillar of our product and engineering culture. We’re looking for a pilot, not a passenger—someone who is intrinsically driven and excited by the prospect of building something from scratch.

This is a role for an engineer who masters the balance between speed and structure. You will have a huge impact on our product, our architecture, and our company's success.

What You'll Do 💻

• Build & Ship: You will design, build, and ship features end-to-end, from our cloud infrastructure to our user-facing web application.

• Own the Codebase: You’ll write clean and maintainable code across our stack (we primarily use TypeScript, React, Node.js (Express), and PostgreSQL).

• Shape the Product: You’ll collaborate closely with the founders to translate customer feedback and business needs into technical solutions.

• Define the Architecture: You will have a crucial voice in the architectural decisions that will support our growth in complexity and scale.

• Build the Culture: You'll help us establish best practices for everything from testing and deployment to code reviews, helping us build an engineering culture we can be proud of.

Who You Are 🙌

You are passionate about technology and building products that people love. You are ambitious, curious, and thrive in an environment where you can take ownership and see the immediate impact of your work.

• A Problem Solver: You enjoy tackling complex technical challenges and finding elegant, practical solutions.

• An Eager Learner: You embrace tasks outside your comfort zone and are motivated to grow your skills and raise the bar for yourself and the team.

• A Self-Starter: You take initiative and thrive on responsibility. In a startup, there's no playbook - you'll help us write it.

• A Team Player: You are a great communicator who thrives in a collaborative environment, giving and receiving constructive feedback.

• Technically Minded: You have some professional or significant project experience building web applications with Typescript and modern frameworks like React/Next.js, Node.js, Vue, or Svelte. You understand relational databases and are comfortable with Git.

Bonus Points If You ✨

• Have hands-on experience with TypeScript across the full stack.

• Are curious about AI/LLMs and their application in building smarter software.

• Have experience in or an interest in FinTech, accounting, or building B2B SaaS products.

What We Offer 💰

• A unique opportunity to shape a product and a company from the ground up. Your work will have a direct and visible impact every single day.

• Close collaboration with and mentorship from experienced founders who have been part of the Danish startup success story.

• A steep learning curve and the opportunity to take on significant responsibility that you won't find in a larger organization.

• The best tools for the job, including a new MacBook Pro and any other equipment you need.

• A competitive salary and a great office in the heart of Copenhagen.

Don't meet every single requirement? If you’re excited about this role but your experience doesn’t perfectly align with every point in the job description, we encourage you to apply anyway. What matters most is your curiosity, ambition, and drive to grow with us.