Senior Rust Engineer (AdTech)

TL;DR

Senior Rust Engineer (AdTech): Building high-performance real-time systems powering ML-driven Mobile Growth Platform with an accent on low-latency, high-load backend services and ML platform components. Focus on developing feature stores, user identity services, custom inference layers, and optimizing infrastructure for scalability and reliability.

Location: Barcelona, Spain (office attendance 4 days per week)

Company

US-based product company leader in mobile app monetization with global presence, offices in Warsaw, Barcelona, and Parkland (FL), and remote team members worldwide.

What you will do

• Develop real-time applications and ML platform components including feature stores, user identity services, and custom inference layers
• Build and maintain high-load, low-latency backend services
• Optimize system performance in on-premise Docker and Kubernetes environments
• Design solutions for traffic scaling, system reliability, and observability
• Collaborate with ML, data, and engineering teams to support production ML systems
• Continuously improve system architecture and efficiency

Requirements

• 5+ years of experience in software engineering
• Strong proficiency in Rust (or C/C++/Zig with willingness to transition to Rust)
• Experience designing and building high-load, performance-critical systems
• Solid understanding of system design, concurrency, and performance optimization
• Basic knowledge of machine learning workflows and tools

Nice to have

• System programming experience (C, C++, Zig)
• Experience in ML engineering / MLOps
• Strong Python skills
• Familiarity with AdTech standards (OpenRTB, MRAID, VAST)
• Experience with WASM / WASI
• Background in distributed systems and real-time processing

Culture & Benefits

• Collaborative and inclusive culture focused on diversity, innovation, and continuous learning
• Opportunity to solve complex, large-scale problems with world-class professionals
• Competitive salary, flexible work arrangements, and comprehensive benefits package
• Professional development and career growth in a fast-growing company
• Positive environment emphasizing impact, growth, and enjoyment