Principal Engineer (AdTech)

Are you an experienced technical leader ready to shape the future of scalable AdTech platforms? We are seeking a Principal Engineer to drive architectural transformation and lead high-impact projects for a Sweden-based industry innovator. This is a senior-level role with full remote flexibility across Europe. At Sigma Software, we partner with global leaders to deliver cutting-edge technology solutions that automate and optimize revenue-focused operations. You will work on strategic initiatives, collaborate with cross-functional teams, and influence technical direction in a fast-paced, evolving domain. Why join us? You’ll have the opportunity to work on globally recognized platforms, contribute to architectural innovation, and enjoy a supportive culture with challenging projects. CUSTOMER Our Customer is a Swedish AdTech company that transforms the way publishers and advertisers interact. They provide state-of-the-art self-serve advertising platforms that enable seamless, direct transactions between advertisers and some of the world’s largest publishers. Their mission is to make advertising more accessible, automated, and efficient through innovative technology. Together, we serve globally recognized clients, including TripAdvisor, Bloomberg, The Washington Post, Opera, Dow Jones, etc. PROJECT The project represents a strategic transition to a Platform-First, API-driven architecture. The company is moving away from monolithic, client-specific codebases to a standardized ecosystem. As a Senior TypeScript/Vue.js Developer, you will be the technical visionary for the platforms, ensuring the technology remains high-performing and scalable. Act as a key technical liaison between business and engineering teams, translating commercial goals into actionable technical solutions Evaluate publisher technical environments and design scalable, maintainable architectures Prepare client-ready solution proposals, including features, integrations, and tools Lead cross-functional delivery teams, including developers, designers, DevOps, and technical PMs Provide architectural oversight throughout the development lifecycle to ensure continuity and quality Manage distributed teams across multiple time zones Mentor engineers, conduct code reviews, and guide technical growth Make architectural decisions at component and plugin levels, balancing trade-offs and communicating choices clearly At least 6+ years of hands-on experience in JavaScript / TypeScript, Vue.js, and Node.js Experience in microservices architecture and distributed systems integration Hands-on experience with AWS Lambda or similar serverless technologies Deep understanding of plugin-based systems and extensibility points Proven ability to customize and extend existing solutions without breaking core functionality Experience in AdTech environments with evolving requirements Knowledge of Vite, Cypress, and Vitest for modern development workflows and testing Experience with AWS S3 and CloudFront for scalable storage and content delivery Strong commercial acumen and ability to translate business goals into technical infrastructure Fluent English communication skills for enterprise stakeholder management WILL BE A PLUS Experience with other serverless frameworks (e.g., Azure Functions, Google Cloud Functions) Familiarity with enterprise e-commerce platforms Knowledge of performance optimization and security best practices Prior work in media publishing technology solutions PERSONAL PROFILE Proactive, solution-oriented mindset Strong problem-solving skills and ability to unblock dependencies Comfortable working in fast-paced environments with evolving requirements System-thinking approach — seeing beyond individual tasks to the bigger picture