Fullstack Engineer (Java&Kotlin + JavaScript)

Codest Ltd. Company No. 12590542, VAT number: GB363431020; Warszawa; On-site; PLN 167,000 - 223,000; Full time

Benefits offered by this job

Worksmile platform access

Job summary

The Codest is seeking a full-stack developer to join a European e-commerce project, working across backend and frontend tasks. You will adjust Java-based APIs, build responsive UI with React, and collaborate with external partners to ensure smooth onboarding.

Expect to switch between backend and frontend duties, implement RESTful services, and handle JSON data. English level B2+ required; great opportunity for growth within a global tech company.

Qualifications

• Strong Java (Kotlin) backend with microservices
• Frontend experience with React, HTML, CSS, JS
• REST API design and JSON data manipulation
• Ability to switch between backend and frontend tasks
• Professional English (B2+)
• Willingness to participate in Incident Response service

Responsibilities

• Backend API adjustments and designing APIs on the Java backend
• Frontend development of responsive components using React
• Integrate with external partners, onboarding support
• Collaborate across full-stack on project requirements

Skills

Java (Kotlin)

Frontend development

REST APIs

JSON data handling

English (B2+)

Tools

GitLab CI

Docker

Cloud environments

Job description

Hello World!

We are The Codest - International Tech Software Company with tech hubs in Poland delivering global IT solutions and projects. Our core values lie in “Customers and People First” approach that prioritises the needs of our customers and a collaborative environment for our employees, enabling us to deliver exceptional products and services.

Our expertise centers on web development, cloud engineering, DevOps and quality. After many years of developing our own product - Yieldbird, which was honored as a laureate of the prestigious Top25 Deloitte awards, we arrived at our mission: to help tech companies build impactful product and scale their IT teams through boosting IT delivery performance. Through our extensive experience with product development challenges, we have become experts in building digital products and scaling IT teams.

But our journey does not end here - we want to continue our growth. If you’re goal-driven and looking for new opportunities, join our team! What awaits you is an enriching and collaborative environment that fosters your growth at every step.

Project description:

Our client is one of the largest e-commerce platforms in Europe, used by millions of users every day. The company connects sellers - from small businesses to global brands - with customers, offering a vast product selection, fast delivery, and a well-crafted shopping experience.

Developers engaged in this project will operate across the full stack, dynamically shifting between backend and frontend tasks depending on current project requirements.

The role:

• Backend & API Adjustments: Preparing backend mocks, designing, and adjusting APIs on the Java backend side.
• Frontend Development: Developing responsive web components, checkout funnels, and registration pathways using the React framework.
• Integration Support: Adapting systems and endpoints to ensure efficient onboarding and cooperation with external partners.

• Good programming skills in Java (Kotlin) and comfortable working with microservices.
• Solid hands-on frontend experience using HTML, CSS, JavaScript, and modern framework ecosystems.
• Clear understanding of REST API principles, JSON data manipulation, and consuming backend endpoints.
• High context-switching capability; eager to work on both backend enablement and web frontend.
• English level min. B2+
• Availability for the Incident Response service.

Nice to have:

• Familiarity with CI/CD tools (Gitlab CI, Docker) and cloud environments.
• An eye for modern UX/UI standards, accessibility, and Responsive Web Design (RWD).

Our offer:

• 15-20k PLN on a B2B contract
• Access to the Worksmile platform
• A work environment that values growth and innovation - you bring the ideas, and we want to hear them

Recruitment process:

• 30-minute screen with our recruiter, Justyna
• Technical Verification Meetings
• Stakeholder meeting
• Offer