Senior Backend Developer

2 weeks ago

Belgrade Novi Sad Nis, Serbia Holycode Full time €60,000 - €80,000 per year

We at Holycode are currently looking for a full-time, experienced, and highly skilled Senior Backend Developer to join the Function 365 team. In this role, you will be responsible for designing, developing, and maintaining a large-scale application, as well as building and integrating back-end systems using GraphQL, JavaScript, , and MySQL.

About Function 365

F365 is the market leader in providing a comprehensive electronic healthcare record solution for private clinics providing preventive and longevity medicine. F365 is trusted by hundreds of healthcare professionals across the UK, EU and USA. Through strategic and meaningful customer relationships F365 provides a continually evolving system to manage all aspects of running private healthcare organisations. F365 is a growing team of young vibrant, dedicated professionals and we fully embrace modern remote working. We're interested in the outcome of your efforts, not how many hours you've been in the office.

What You'll Do

  • Design, Develop and maintain GraphQL APIs for internal and external consumption
  • Develop and maintain API integration of the F365 application with 3rd party API services
  • Write clean, well-documented, and testable code using industry-standard coding practices.
  • Participate in code reviews and provide guidance to junior developers.
  • Implement tests (Unit, integration)
  • Refactoring and bottleneck optimizing
  • Participating in setting up CI/CD processes
  • Implementing monitoring (Grafana)

Requirements

  • Direct experience with GraphQL API design, implementation and upgrade
  • Direct experience with RESTful API implementation, and upgrade
  • 4 years of relevant experience MySQL
  • Strong knowledge of JavaScript and PHP
  • Good knowledge of Symfony 6.x and MDB
  • Experience with Relational DB
  • Strong direct experience with integration of external API's from other projects you've worked on
  • Strong direct experience with developing internal API for internal and external consumption
  • Knowledge of common accepted software design principles (design patterns, anti-patterns,
  • refactoring, etc)
  • Strong problem-solving and debugging skills.
  • Proficient with version control systems (Git)
  • Good knowledge of Linux-like operating systems
    • Knowledge of basic algorithms and data structures
  • Knowledge of AWS
  • Excellent/Fluent English level.

It Helps If You Have

  • Experience with front-end testing frameworks (e.g., Jasmine, Karma) and back-end testing
  • frameworks (e.g., Jest, Mocha).
  • Knowledge of cloud platforms and deployment processes (e.g., AWS, Azure).
  • Familiarity with agile methodologies and project management tools.
  • Familiarity with UI/UX design principles and accessibility standards.
  • Familiarity with front-end and back-end performance optimization techniques.

Why you'll love working here:

  • Private health insurance
  • Flexible work model – full remote or hybrid
  • Equipment of your choice (laptop, monitor, accessories)
  • High-growth company with innovative products
  • Supportive, international team
  • Budget for professional development (courses, books, conferences)
  • English and German language lessons during working hours
  • Nice office in Belgrade with a stocked kitchen and game area
  • Opportunity to learn, grow, and make a real impact

If you are looking for an environment where you can grow professionally, learn from the best in the field, balance work and life habits and have a pleasant and enthusiastic environment, please submit your CV in English.

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