Senior TypeScript/Node.js Developer (Swedish Ad Platform)

Are you passionate about building high-performance platforms that serve millions of users worldwide? We are looking for a Senior TypeScript/Node.js Developer to join our team and help transform a global AdTech product into a scalable, platform-first architecture.

At Sigma Software, we value engineering excellence, innovation, and collaboration, offering the opportunity to work on cutting-edge projects with world-class customers.

You will have the chance to work with advanced AWS serverless solutions, contribute to strategic architectural decisions, and enjoy a supportive environment with professional growth opportunities.

CUSTOMER

Our Customer is a Sweden-based AdTech company specializing in advanced self-serve advertising platforms that automate direct transactions between advertisers and major global publishers. Their technology removes traditional friction in ad sales by enabling automation, transparency, and operational efficiency at scale. Platforms are trusted by internationally recognized publishers including TripAdvisor, Bloomberg, The Washington Post, Opera, and Dow Jones, handling millions of transactions worldwide. 

PROJECT

The project is a strategic architectural transformation toward a Platform-First approach. The company is transitioning from monolithic, client-specific implementations to a standardized, API-driven, multi-tenant ecosystem of reusable microservices. These services power the entire product suite, remaining independent, scalable, and decoupled from frontend or customer-specific customization.

Key Technologies: TypeScript, Node.js, AWS Lambda, API Gateway, DynamoDB, EventBridge, IaC tools (CloudFormation or Terraform), RESTful/GraphQL APIs.

WILL BE A PLUS

• Experience as a Lead Back-End Developer

PERSONAL PROFILE

• Proactive and detail-oriented with a strong sense of ownership

• Enjoys solving complex architectural challenges

• Thrives in collaborative, cross-functional teams

• Committed to delivering high-quality solutions meeting demanding performance and reliability standards