Frontend Engineer (Lead)

Open position in 🇸🇮 Ljubljana, Slovenia

tretton37 (thirteen37 -> 13 I 37) is an international technology company with more than 85% of our colleagues employed in technology roles. We are looking for talented people to join us in our “I-want-to-live-here” offices in the heart of Ljubljana. Are you a Frontend developer? Do you live and breathe the world of custom software and immersive user interfaces? Welcome to the beginning of your new chapter, something fresh, different, and scändinåviën.

What will you do?

You will be working in an agile environment, developing highly performant interfaces with an emphasis on user experience. Your development work will directly empower organizations with internal tools and help their products meet consumer needs.

  • You will ideate and develop solutions for various technical challenges in cross-functional teams.
  • You will actively participate in system architecture and product decisions.
  • You will build impressive and immersive frontends that enhance the end user’s quality of life and natural abilities.
  • You will proactively help your colleagues grow and work better through code reviews, pair programming, and other extreme programming practices.
  • You will continuously enhance ways of working regarding people, relationships, processes, and tools.
  • You will participate in discussions, facilitate workshops, and share knowledge about your topics of expertise.
  • You will work in a distributed team with co-located and remote colleagues.

What are our expectations?

We are looking for a knowledgeable and driven individual with senior expert (lead) levels of professional experience to reinforce our digital teams. Above years of experience and past job titles, the key attributes we are after are a passion for delivering high-quality work, an ambition to get the job done, and an enthusiasm for continuous improvements. In senior roles, we expect our employees to be value multipliers in our company, helping us advance our colleagues, our company, and our culture.

Those who succeed in this role usually have:

  • At least 7+ years of relevant professional experience
  • Excellent written and verbal communication skills in English
  • A passion for technology, sharing knowledge, and enabling others
  • High attention to detail, user experience, and responsive design
  • A fundamental understanding of JavaScript, its runtimes, and asynchronous programming
  • Experience with at least one major frontend framework (React, Vue, or Angular)
  • Proficiency with either OOP or functional programming paradigms
  • Experience with various state management tools and patterns
  • Experience with event-driven architecture
  • Excellent knowledge of HTML, CSS, and the browser render cycle
  • $ git commit (often)
  • A tool belt equipped with Webpack, Babel, npm, and performance tools.

You will make us extra excited with:

  • Exceptional dedication to the community through your commitment to open-source or other visible initiatives.
  • Experience in working with heavy frontend clients (integrating with REST and GraphQL, Authentication, Web Assembly, Service workers, Web workers).
  • Experience with either native or multi-platform development (Flutter, React Native).
  • Experience working with Firebase or other serverless services.

What are we offering

_financial aspect 💸

  • Transparent salary range depending on your experience and responsibilities
  • Annual salary progression
  • Highest payouts within meal and transportation compensation, maximum annual holiday allowance payout (i.e., regres), and Christmas bonus
  • Payday on the 25th of the month for the current month
  • Full-time indefinite employment with an immersive 6-month trial period

_wellbeing and health 🧘

  • A minimum of 25 days of paid annual leave
  • Additional monthly payments into your third-pillar pension fund
  • 1337 basketball club and other team sport activities
  • Office massage sessions
  • Guided mindfulness meditation
  • Healthy snacks, fruit and fully stocked fridge
  • Ergonomic adjustable hydraulic desks, high-quality chairs, adjustable and glare-free screens and other tools with an emphasis on a comfortable work environment

_your upgrade and gear 💻

  • Generous knowledge budget to be spent on conferences, additional tools, education, licenses, and gadgets every year
  • Monthly 1:1 sessions with a team lead with regular check-ins in between, helping you advance your professional aspirations
  • Organized knowledge days 3x a year, every time in a unique location 
  • Employee-driven competence groups with specific knowledge or topical interests supported with resources from tretton37
  • Leadership trainings
  • A minimum of 2 extra days of paid leave to use for your personal and professional growth
  • A brand new flagship laptop of choice (Macbook Pro, XPS…)
  • A brand new flagship phone of choice (iPhone 12, S21…) including a data plan

_your second home and events ☕

  • Full access and use of our premises, 24/7
  • Creative and relaxed environment: board games, PS5, SNES
  • Our own library
  • Flexible working hours
  • A remote-friendly company with flexible policies in terms of where you can work form
  • Unlimited artisan coffee, soft drinks, and craft beers
  • Voluntary participation in international trips and team building activities
  • Summer and Christmas party for our employees and their families
  • Culinary days (Friday Fika, Codelunch, Leetlunch, Intro Dinner, Leet Ladies Lunch)
  • Fun after-work activities and events (code nights, movie nights, Eurovision viewing, go-kart races, quiz & trivia nights, board game nights, Magic the gathering tournament)
  • Support for open-source projects and community engagement

_challenges and day-to-day 🚀

  • Carefully curated projects to challenge you in every way
  • Work with large international clients, unicorn startups, and early-stage companies solving meaningful problems
  • Impressive colleagues and mentors at every corner
  • Scandinavian approach with a flat organizational structure
  • Complete transparency on business decisions and participation in monthly meetings with influence on our future growth
  • Opportunities to gain international experience in any of our offices abroad


If you would like to join us in Ljubljana as our new Frontend Engineer, please click here to apply now.