Senior Backend Engineer - Node.JS (Romania, remote, f/m/d)

YOUR MISSION We are looking for an experienced Senior Backend Engineer to expand and optimize our digital advertisement SaaS suite of applications. Using technologies such as NodeJS with TypeScript, NestJS federated GraphQL, Docker, AWS and Apache Kafka, you'll be designing microservices and other back-end components, and integrating data storage, monitoring and protection solutions. Your primary focus will be the development of all server-side logic, definition and maintenance of central databases and message busses, and ensuring high performance and responsiveness to requests from the front-end. Additionally you'll conduct regular code reviews, provide guidance to other team members, and contribute to workload estimations, project planning and architecture discussions. You will join a cross-functional team under a Product Owner to contribute to our multi-tenant SaaS product and ad-serving network. To ensure success as a Senior Backend Engineer at Factor-Eleven, you should possess extensive knowledge of NodeJS based services, good knowledge of AWS and/or Kafka, great knowledge of GraphQL/REST-APIs and experience in a similar role. An accomplished Senior Backend Engineer will be someone whose expertise results in the stable, fast, and secure exchange of data between servers and end-users, and who successfully shares that expertise with the wider team. This is a high-impact role for someone who thrives on elevating engineering standards, and driving a forward-thinking, AI-first approach across the organization. Ultimately, a top-class Backend Engineer at F11 should be able to envision, plan, develop, test and deliver scalable microservices in an event-driven multi-tenant architecture, and teach others to do the same. YOUR RESPONSIBILITIES Developing and maintaining microservices and back-end components. Ensuring optimal performance of databases and responsiveness to front-end requests. Collaborating with developers, product owners and stakeholders on the design and integration of elements. Developing high-performance applications by writing testable, reusable, and efficient code. Implementing effective security protocols, data protection measures, and storage solutions. Running diagnostic tests, repairing defects, and providing technical support. Documenting server-side processes, including database schemas, message events and sagas, as well as preparing reports. Recommending and implementing improvements to processes and technologies. Provide mentorship and technical supervision to team-members. Requirements YOUR PROFILE 5+ years experience as Backend Engineer or similar role. Strong proficiency of NodeJS with TypeScript, web stacks, libraries, and frameworks. Working knowledge of front-end technologies such as HTML5 and CSS3. Experience with user authentication and authorization between multiple systems, servers, and environments. High familiarity with fundamental design principles behind scalable applications. Creating database schemas that represent and support business processes. Good knowledge of event-driven architecture, message busses, and/or pub/sub-systems. Proven expert knowledge Implementing automated testing platforms and unit tests. Superb interpersonal, communication, and collaboration skills. Excellent familiarity with git, npm, docker and Jira. Extensive experience in mentoring teammates in a respectful, educative manner. Using AI tools such as Junie/Cursor (nice to have) Benefits WHY US? Factor Eleven 's tech department is the inhouse tech scale-up responsible for our SaaS product suite offering localized digital advertising to enterprises of all sizes and shapes. We're powering the engine that Factor Eleven is successfully built upon and elevate the possibilities of our product on a daily basis. We're working together to fulfill our ambitions as a top ad-tech provider by continuously leveling up the quality and expanding capabilities of the entire platform, as well as our engineering and product organization. Join our amazing team in our mission to move digital localized advertisement forward and enjoy the freedom, camaraderie and perks of our fully remote operations. OUR PERKS BENEFITS Transparent, above-market salaries 100% remote within Europe Flexible work-hours and part-time models Be part of a fast-growing, highly-skilled team In person department and company events Home office, co-working space and work-together allowance Personal and professional development courses from Udemy Case by case relocation and visa support Please note that you need to be residing in and hold a work permit of a country in the European Union to be considered for this role. Originally posted on Himalayas