Senior Backend Developer

About the Position

Join the Future of Digital Tech with Kolomolo

At Kolomolo, we don’t just follow trends - we set them. As a global supplier of IT services and digital modernization solutions, we help businesses embrace cutting-edge technology to optimize their operations. Now, we are growing and looking for fresh talent to grow with us.

Are you proactive, tech-savvy, and eager to build your career in IT? This role could be your perfect fit.

Location: Tumba, Sweden (Hybrid)

Contract: B2B, Full-Time

About the Role

Are you a backend developer who enjoys solving real-world problems with clean, scalable code? Do you want your work to have a meaningful impact beyond the screen? At Kolomolo, we are looking for a technically driven and collaborative Senior Backend Developer to join our cross-functional team developing our digital platform supporting modern dairy farmers around the world.

In this role, you will work closely with Product Owners, Project Managers, Scrum Masters, UX Designers, QA Engineers, and other developers to build and maintain the backend services powering our website. You will be involved in the entire feature lifecycle - from design and development to testing, deployment, monitoring, and incident handling.

You will build and evolve backend functionality that supports Service Technicians and Installers in their daily work. This includes solutions for installation, configuration, equipment health monitoring, troubleshooting, sw/fw update orchestration, device lifecycle orchestration, and IoT-enabled services. You will help shape robust, secure, scalable, and observable backend services using modern, cloud-native technologies.

This role is ideal for someone who’s excited to deliver reliable systems at scale, enjoys working with data-intensive applications, and is passionate about making a difference in the lives of real users.

Responsibilities

• Design, build, and maintain backend services for our platform;
• Collaborate with a cross-functional team to deliver high-quality features end to end;
• Write secure and testable APIs following OWASP and clean code principles;
• Manage infrastructure and deployments using modern IaC and DevOps tools;
• Work on data-heavy services that are central to our platform’s performance and reliability;
• Monitor services in production, respond to incidents, and continuously improve system resilience;
• Contribute to our culture of learning and knowledge sharing.

Requirements

• At least 7 years of backend development experience;
• Solid foundation in computer science, with strong knowledge of algorithms, data structures, and system design;
• Languages & Runtime: JavaScript, TypeScript, Node.js, npm;
• Cloud & Infrastructure: AWS (Lambda, S3, DynamoDB, RDS, VPC), CDK, Kubernetes, Terraform;
• Architecture & Patterns: REST API development, API security (authentication, authorization, OWASP best practices), event-driven architecture;
• Testing & Quality: Jest (unit testing), Cypress (E2E), JMeter (load testing), SonarQube;
• DevOps & Observability: Git, CI/CD pipelines, Docker, Grafana, Loki, Sentry, OpsGenie;
• Best Practices: Clean code, secure coding, code reviews, production monitoring, incident response;
• Special Focus: Experience working with data-intensive and high-traffic applications;
• Fluent in English (required) and preferably also in Swedish;
• Able and willing to work from our Tumba office at least 3 days per week.

Nice to Have

• Experience handling incidents and working with customer service to improve production systems;
• Experience with production-grade systems and understanding the importance of quality, reliability, and supportability.

We Offer

• Competitive salary and benefits;
• Career development opportunities in a growing tech company;
• Continuous learning culture: mentorship, internal training, and certifications;
• Flexible, agile work environment (hybrid in Tumba);
• Office perks: great coffee, tea, fresh fruit, snacks, and a fun atmosphere;
• Flat management structure, where your voice matters;
• Regular team events and a social, supportive work culture;
• B2B contract or Contract of Mandate (Umowa Zlecenie);

About the Company

To be leaders in digital modernization by helping companies embrace the latest cutting-edge technologies to optimize their business with the help of our talented experts.

Founded in 2016, Kolomolo has about 100 co-workers and a turnover of 5M.

Join Kolomolo and elevate your career with cutting-edge technology, a supportive team, and a company that truly values your input.

Ready for the next step? Apply now and start an exciting journey of growth and innovation with us!