Senior Software Engineer

Merkle powers the experience economy. For more than 35 years, the company has put people at the heart of its approach to digital business transformation. As the only integrated experience consultancy in the world with a heritage in data science and business performance, Merkle delivers holistic, end-to-end experiences that drive growth, engagement, and loyalty. With more than 16,000 employees, Merkle operates in 30+ countries throughout the Americas, EMEA, and APAC.

In Bulgaria, we manage a global portfolio of clients, providing a single source of expertise, technology, and operational support. We have a proven track record for delivering, managing, and innovating multi-channel commerce platforms for major international brands and retailers, including adidas, Clarins, ASDA, Shiseido, and more. Our world-class team has delivered sites for over 35 brands with more than 400 transactional e-commerce sites in 60 locations and on 6 continents. Our scope is expanding with the addition of a new data engineering practice, paid search and social advertising, and SEO, and we are looking forward to what’s next.

We’re hiring a Senior Full-Stack Developer as part of Merkle in Sofia.

Key Responsibilities:

• Design, develop, and maintain scalable web applications using React and Node.js / Salesforce B2C Commerce Cloud.
• Collaborate with cross-functional teams to define, design, and ship new features.
• Ensure the performance, quality, and responsiveness of applications, focusing on both frontend and backend optimizations.
• Identify and resolve performance bottlenecks, implement caching strategies, and fine-tune database queries.
• Integrate and manage third-party services such as payment gateways, shipping providers, and external APIs.
• Work with Salesforce B2C Commerce Cloud (Demandware) on customisations, cartridge development, and integrations (recommended).
• Write and maintain unit and integration tests using frameworks such as Chai, Mocha, and React Testing Library.
• Implement and manage continuous integration and deployment (CI/CD) pipelines.
• Maintain code quality, organisation, and automation.
• Mentor and guide junior engineers, providing technical leadership and thorough code reviews.

Required Skills and Qualifications:

• 5+ years of professional experience in full-stack development.
• Proficiency in React and Node.js.
• Experience working with Salesforce B2C Commerce Cloud (Demandware) is highly recommended.
• Strong understanding of performance optimisation techniques across frontend and backend.
• Proven experience with integrating 3rd-party services (e.g., payment processors, shipping APIs, CMS, search).
• Experience with unit testing frameworks such as Chai, Mocha, and React Testing Library.
• Experience with version control systems (e.g., Git).
• Familiarity with Agile/Scrum methodologies.
• Excellent problem-solving skills and attention to detail.
• Strong communication and collaboration skills.

What do we offer:

• We are huge believers in work-life balance, so we offer all our employees 25 days of paid leave and 3 fixed wellness days off a year
• A hybrid work model for our teams so they can work from the office or the comfort of their home
• Free parking spaces for all our employees working from the office
• Complimentary drinks and snacks in the office to keep the energy levels up
• Parent-friendly culture and potential for additional days off to create new memories with your loved ones
• Life Insurance, Health and dental insurance plan or, if selected, gift vouchers instead
• Sports card, partially covered by the company and food vouchers
• 2 days off for volunteering and numerous charity initiatives throughout the year
• Opportunity to attend training, conferences and get certification sponsored by the company upon availability and business need

About dentsu:

Taking a people-centred approach to business transformation, we use insights to connect brand, content, commerce and experience, underpinned by modern creativity. As part of Dentsu Group Inc., we are headquartered in Tokyo, Japan, and our 65,000-employee base of dedicated professionals works across four regions (Japan, Americas, EMEA and APAC). Dentsu combines Japanese innovation with a diverse, global perspective to drive client growth and to shape society.