Allow us to introduce ourselves
Hello there We’re Appinio, a integral market research company that combines an AI-powered insights platform with expert consultancy. On a mission to make the world a little more fact-based, we help companies understand how consumers think and make smarter decisions.
We started out in Hamburg back in 2014, but we’re now humbled to call the world our playground, with over 260 employees spread across 13 countries (we’re remote-first), 2600+ international clients, delivering research from +190 markets, globally.
Want to be a part of the Appinio movement? ?
Here at Appinio, we value transparency in our recruitment process, and we've created a blog to share what to expect during each step of our journey together: here
Your mission as a Senior Backend Engineer
We are looking for a passionate (Senior) Backend Engineer (m/f/d) to join our amazing backend team. In this role, you will be responsible for developing new features and enhancing our existing code base using NodeJs, Express, and MongoDB.
What you’ll be doing




Design and maintain server-side applications and database architecture.
Collaborate with front-end developers for a seamless user experience.
Regularly review and improve code and system efficiency.
Develop and deploy reusable, testable code and automated tests
You will thrive in this role if
You have at least 3 years of hands-on experience with Node.js, along with strong proficiency in TypeScript and Express.
You have practical experience working with NoSQL databases, preferably MongoDB.
You have a solid understanding of object-oriented programming principles.
You hold a degree in Computer Science or a related field – or have completed a comparable vocational training
Having AWS (S3, ECS, EC2), Docker and Terraform experience is a plus
Having previous experience with NestJS is a plus
You are a proactive problem solver, always seeking innovative solutions and continuously improving processes.
You are willing and able to get familiar

📌 Senior Backend Engineer (Madrid)
🏢 Appinio
📍 Madrid