Are you passionate about building intelligent, scalable, and high-performance platforms powered by AI technologies? We are looking for a Middle/Senior AI & Back-End Developer to join Sigma Software and contribute to the transformation of a global AdTech product into a modern AI-enabled ecosystem.

In this remote-friendly role, you will work with cutting-edge cloud-native and AI technologies, helping shape a Platform-First architecture built around reusable microservices, serverless infrastructure, and intelligent automation capabilities.

We at Sigma Software value engineering excellence, innovation, and collaboration. You will have an opportunity to work on a product trusted by globally recognized publishers while growing your expertise in AI integrations, cloud platforms, and scalable distributed systems.

CUSTOMER

Our Customer is a Sweden-based AdTech company specializing in advanced self-serve advertising platforms that automate direct transactions between advertisers and premium global publishers. Their solutions improve transparency and operational efficiency in digital advertising and are trusted by globally recognized brands such as TripAdvisor, Bloomberg, The Washington Post, Opera, and Dow Jones. The company processes millions of advertising transactions worldwide and actively invests in AI-driven automation and intelligent data capabilities.

PROJECT

The project focuses on the strategic transformation of an existing AdTech ecosystem toward a Platform-First, AI-enabled architecture. The Customer is transitioning from monolithic and client-specific implementations into a scalable, API-driven, multi-tenant ecosystem powered by reusable microservices and intelligent services.

The team is building modern cloud-native solutions using AWS serverless technologies while introducing AI-assisted automation, recommendation systems, workflow optimization, data enrichment, and LLM-powered capabilities across the advertising lifecycle.

Key Technologies: TypeScript, Node.js, AWS Lambda, API Gateway, DynamoDB, EventBridge, OpenAI APIs, GraphQL, RESTful APIs, Terraform, CloudFormation, Vector Databases

• Develop and maintain high-performance Back-end microservices and AI-enabled services using TypeScript and Node.js
• Design, implement, and integrate AI and LLM-powered platform features
• Build scalable serverless solutions using AWS Lambda, API Gateway, DynamoDB, and EventBridge
• Collaborate with cross-functional teams on API-first architecture and OpenAPI specifications
• Ensure tenant data isolation and compliance with established AdTech data models
• Contribute to reusable libraries, templates, AI integration patterns, and engineering standards
• Participate in code reviews focused on performance, reliability, observability, and service quality
• Translate product and AI feature requirements into scalable technical solutions
• Support the platform transformation toward automation, standardization, and intelligent reusability
• Contribute to continuous improvement initiatives and technical decision-making processes

• 3+ years of commercial experience as a Back-end Developer or AI Software Developer
• Strong hands-on experience with TypeScript and Node.js
• Experience building API-first microservice architectures
• Practical experience integrating AI services, LLM APIs, or AI-assisted workflows
• Hands-on experience with AWS serverless technologies including Lambda, API Gateway, DynamoDB, and EventBridge
• Understanding of RESTful and GraphQL APIs
• Knowledge of prompt engineering concepts and AI integration approaches
• Understanding of multi-tenant architectures and logical data isolation principles
• Interest in AdTech products, automation, and AI-driven optimization
• Upper-Intermediate or higher English level

WILL BE A PLUS

• Experience with ML and AI experimentation projects
• Exposure to recommendation systems or data intelligence platforms
• Experience working with vector databases
• Familiarity with Infrastructure as Code tools such as Terraform or CloudFormation
• Understanding of observability and monitoring practices in distributed systems
• Experience working with scalable cloud-native architectures

PERSONAL PROFILE

• Strong analytical and problem-solving skills
• Proactive and ownership-driven mindset
• Passion for modern Back-end engineering and AI technologies
• Ability to collaborate effectively within distributed international teams
• Interest in innovation, experimentation, and continuous learning
• Strong communication skills and attention to engineering quality