Senior Backend Developer

Senior Backend Developer

Location: Kraków Poland

Experience: 5 years

Contract: B2B Full-Time

Join the Future of Digital Tech with Kolomolo

At Kolomolo we dont 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.

About the Role

Were looking for a Senior Backend Developer who enjoys building reliable scalable and modern cloud-native applications.

In this role youll be responsible for backend feature development system modernization test automation code refactoring and production deployments. Youll work on distributed systems and microservice-based architectures while contributing to the design and development of secure and high-performing backend solutions.

This role is ideal for someone who combines strong technical expertise with a collaborative mindset and enjoys working in agile engineering-driven environments.

What Youll Be Doing

• Develop microservices based on Typescript & NodeJS for core business components.

• Design and develop companys internal IAM microservice preparing for a migration on a new solution.

• Design and develop cloud native applications based on AWS services like Lambda API Gateway DynamoDB and EventBridge.

• Creating and running automated tests particularly integration tests and end-to-end tests for the backend layer.

• Work closely with Architects & SRE to follow security & reliability standards while being actively involved in architectural discussions.

• Work with external partners & vendors while developing various integrations.

• Collaborate with the team and drive it while ensuring high code quality and standards.

• Be actively involved in designing and developing reliable & secure backend features/functions.

• Work with continuously delivered (CI/CD) asynchronous and distributed systems

Tech stack

• Runtime: Serverless (Lambda API Gateway EventBridge)

• Backend: NodeJS / Typescript (additional Java or Python)

• Persistency: DynamoDB S3 SNS SQS

• Architecture: Microservices

• IAM: oAuth2 OIDC Connect JWT OPAL

• CI/CD: GitLab

• QA: Playwright/ Postman/ Jest

• Infrastructure: AWS Kubernetes AWS CDK Terraform

What We Are Looking For

• Min. 5 years of experience as a backend/full stack developer with recent projects in TypeScript & NodeJS and other backend programming language (preferably Java or Python).

• Experience in creating and running test automation with holistic approach including system performance smoke and E2E tests (full testing pyramid) on Jest/Postman/Playwright.

• Ability to share your knowledge experiences and opinions on the forum via technology demos/brainstorming sessions.

• Willingness to grow and learn with a passion for creating new solutions.

• Experience in working closely with product and design teams as well as doing pair programming in small agile and cross-functional teams.

• Ability and openness to work in a team especially within a culture of mutual respect and continuous feedback.

• Being a Team Player able to help people to grow and guide decision-making processes.

• Open minded communicative and focused on delivering business value.

• Fluent verbal and written skills in Polish and English.

Nice to Have

• Familiarity with Customer Identity Access Management systems & solutions (CIAM) ideally with proven record in designing and implementing.

• Experience in Infrastructure as a code especially Terraform/ AWS CDK.

• Developing & maintaining teams monitoring dashboards in Grafana stack (Prometheus Looki).

What is in It for You

• Competitive salary and benefits.

• Career development opportunities in a growing tech company.

• Continuous learning culture: mentorship internal training and certifications.

• Flexible agile work environment (remote hybrid or on-site in Kraków).

• 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.

• Independent Contractor.

Why Join Kolomolo

At Kolomolo we prioritize innovation agility and autonomy. Our teams have the freedom to own their work share ideas and make meaningful contributions. Inspired by Scandinavian values we believe in work-life harmony and creating an inclusive culture where everyone thrives.

You will be part of a passionate skilled and friendly team that works hard and celebrates together. Here you can build your career on your own terms with opportunities to grow learn and make a real impact.

Our Flat Structure & The Culture of Inclusion

At Kolomolo we break the corporate mold. We offer:

• Agile Teams & Autonomy: No micromanagement. Youll own your projects and enjoy the freedom to innovate.

• Work-Life Harmony: Inspired by Scandinavian values we prioritize balance and flexibility where remote work and asynchronous collaboration are in our DNA.

• Learning & Growth: Continuous learning is at our core. We reward hard work value smart ideas and foster an environment of mutual respect and trust.

• Inclusive Culture: We believe in DEI: diversity equity and inclusion. We are committed to creating an environment where every individual regardless of background identity or experience feels valued respected and empowered to thrive.

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!