Senior Fullstack Engineer - Build Scalable Ad Tech (Hybrid)

Smartlyio; Helsinki; Hybrid; EUR 90,000 - 140,000; Full time

Benefits offered by this job

Equity options

Competitive compensation

Career development opportunities

Healthcare packages

Paid holidays and family leave

Hybrid workplace

Ability to work abroad up to 30 days

Job summary

Smartly is seeking a Senior Fullstack Engineer to join our Helsinki-based team and help shape the future of our multi-channel advertising platform. You’ll expand into new channels, develop greenfield integrations, and scale existing ones like Pinterest.

You’ll design systems that power automation for major advertisers, collaborating with partners such as Google, Reddit and Spotify to enable campaign launch, optimization, and iteration at scale.

Qualifications

• 5+ years of experience building and operating production-grade systems with Node.js and TypeScript.
• Solid frontend experience with React and modern web development practices.
• Experience designing distributed systems and working with asynchronous, event-driven architectures.
• Proven ability to build scalable systems that handle high data volumes.
• Ability to take ownership of complex problems and drive them to production.
• Strong collaboration skills across teams and disciplines.
• Interest in mentoring and contributing to team engineering practices.
• Hybrid work setup from Helsinki office (3 days per week).

Responsibilities

• Own the design and implementation of new platform integrations end-to-end.
• Design and operate distributed, data-intensive systems and microservices at scale.
• Build automation systems that process large volumes of campaign data.
• Develop and evolve client-facing APIs and backend services.
• Drive architectural decisions and contribute to long-term technical direction.
• Work across teams to align on shared patterns and unify channel behavior within the platform.
• Partner closely with product and design to shape solutions, not just implement them.
• Mentor other engineers and raise the bar for engineering quality and practices.

Skills

Node.js

TypeScript

React

Distributed systems

Event-driven

Data processing

Microservices

Team collaboration

Mentoring

Tools

PostgreSQL

RabbitMQ

Redis

Kubernetes

Job description

Smartly is seeking a Senior Fullstack Engineer to join our Helsinki-based team and help shape the future of our multi-channel advertising platform. You’ll expand into new channels, develop greenfield integrations, and scale existing ones like Pinterest.

You’ll design systems that power automation for major advertisers, collaborating with partners such as Google, Reddit and Spotify to enable campaign launch, optimization, and iteration at scale.