Senior Rust Engineer

About Appodeal

Appodeal is a dynamic US-based product company with a truly global presence.

We have offices in Warsaw, Barcelona, and Parkland (FL), along with remote team members located around the world.

Our company thrives on diversity, collaboration, and innovation, making us a leader in the mobile app monetization space.

Why Appodeal?

At Appodeal, we’re more than just a company—we’re a team united by a common mission:
Help people discover and grow their talents through products that enable successful mobile app businesses.

We take pride in our cutting-edge product and our internationally distributed team of talented professionals.

Here’s what we value:

• Continuous Learning and Growth – We invest in development and long-term careers
• Making an Impact – We are building a history-defining company in the mobile industry
• Solving Exciting Challenges – Complex, large-scale problems are part of our daily work
• Enjoying the Journey – We believe great results come with a positive environment

About the Role

We are looking for a Senior Rust Engineer to join our Barcelona team and contribute to building high-performance, real-time systems powering our ML-driven AdTech platform (Mobile Growth Platform).

In this role, you will work on core backend infrastructure and ML platform components, focusing on low-latency, high-load services that process large-scale traffic in real time.

You will play a key role in developing and optimizing systems such as real-time applications, feature stores, user identity services, and custom inference layers, ensuring scalability, reliability, and performance.

Responsibilities

• Contribute to the development of real-time applications and ML platform components
• Build and maintain high-load, low-latency backend services
• Work on in-house solutions including:
  • Feature stores
  • User identity services
  • Custom inference layer
  • ML platform infrastructure
• Optimize system performance across on-premise Docker & Kubernetes environments
• Design and implement solutions for traffic scaling and system reliability
• Collaborate with ML, data, and engineering teams to support production ML systems
• Continuously improve system architecture, observability, and efficiency

Tech Stack

• Languages: Rust, Python
• Data & Streaming: Kafka, SQL, Redis, ScyllaDB, Delta Lake, Databricks
• Infrastructure: Docker, Kubernetes (on-premise)
• Tools: GitHub

Requirements

• 5+ years of experience in software engineering
• Strong proficiency in Rust
  or
  proficiency in 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
• Location: Barcelona, Spain (office attendance 4 days per week)

What We’re Looking For

• Autonomous and self-driven engineer with strong ownership mindset
• Passion for engineering excellence, performance, and scalability
• Interest in ML/AI systems and infrastructure
• Ability to work independently and make informed decisions
• Strong collaboration and communication skills

Why Join Us:

• Opportunity to work on cutting-edge projects with a global impact in the mobile app industry.
• A collaborative and inclusive work culture that values innovation and continuous learning.
• Competitive salary, flexible work arrangements, and a comprehensive benefits package.
• Professional development opportunities and career growth prospects within a fast-growing company.

We appreciate teamwork, critical thinking, independent decision-making, and standing up for oneʼs viewpoint.
We are looking for talented engineers who are willing to grow, improve and share our values!