Front-end developer

2 weeks ago

Belgrade, Central Serbia First Line Software Full time €60,000 - €80,000 per year
About the job Front-end developer (React Optimizely)

About the Company

First Line Software works with some of the world's top businesses and organizations in industries like healthcare, data engineering, warehouse automation, retail digitalization, mobile app development, and e-commerce. Our projects are as varied as our people, and our people are as talented as they come. We prefer working as a transparent and supportive team, who shares our knowledge as well as our success.

Let's see what we can create together.

Project Information:

Building high-performance, user-centric digital experience websites aimed at delivering personalized content and seamless user journeys. The project leverages Optimizely for content management alongside a React-based frontend.

Responsibilities:

  • Develop responsive, user-friendly web interfaces using and integrate them with Optimizely CMS
  • Collaborate with designers, UX specialists, and back-end teams to deliver seamless, consistent digital experiences
  • Implement reusable components and optimize front-end performance for speed and scalability
  • Build headless or hybrid front-end solutions using Optimizely's APIs and services
  • Ensure compliance with accessibility (WCAG), SEO best practices, and cross-browser compatibility
  • Maintain clean, maintainable, well-documented code and participate in code reviews
  • Contribute to technical discussions, architectural decisions, and innovative solution design
  • Stay up to date with modern front-end trends, tools, and Optimizely advancements

Requirements:

  • 3 years of professional front-end development experience

  • Strong expertise in , JavaScript (ES6 ), HTML5,

    CSS3, and responsive design principles
  • Hands-on experience with Optimizely CMS (minimum 1 year, headless or traditional setup)
  • Solid understanding of RESTful API integration and JSON-based data handling
  • Experience with modern front-end build tools (Webpack, Vite, etc.)
  • Familiarity with version control (Git) and Agile development processes
  • Passion for clean code, performance optimization, and pixel-perfect implementation

  • Excellent communication and collaboration skills

Must have:

  • (advanced proficiency)

  • JavaScript (ES6 )

  • Experience with Optimizely CMS (headless)

  • HTML5

  • CSS3

Nice to have:

  • Experience with TypeScript
  • Familiarity with Optimizely Content Delivery API and Personalization features
  • Knowledge of GraphQL and modern state management libraries (Redux, Zustand, etc.)
  • Exposure to testing frameworks (Jest, Cypress)
  • Understanding of headless CMS architectures and JAMstack principles
  • Optimizely or front-end development certifications

The FLS difference

  • Our modern stack projects are the right mix of exciting and challenging

  • Gain access to our diverse range of training programs, courses, and certifications

  • Choose your work style - remote, on-site or hybrid in one of our stunning offices. We offer the freedom of flexible working hours

  • Enhance your language skills with our corporate English classes

  • Work from anywhere and explore the world with our Workation program

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