Senior Mobile Engineer

Relay is fundamentally reshaping how goods move in an online era. Backed by Europe’s largest-ever logistics Series A ($35M), led by deep-tech investors Plural (whose portfolio spans fusion energy and space exploration), Relay is scaling faster than 99.98% of venture-backed startups. We're assembling the most talent-dense team the logistics industry has ever seen

Relay’s Mission is to free commerce from friction. Today, high delivery costs act as a hidden tax on e-commerce, quietly shaping what can be sold online and limiting who can participate. We envision a world where more goods move more freely between more people, making the online shopping experience seamless and accessible to everyone.

THE TEAM

• ~110 people, more than half in engineering, product and data
• 45+ advanced degrees across computer science, mathematics and operations research
• Thousands of data points captured, calculated, analysed and predicted for every single parcel we handle
• An intellectually vibrant culture of first‑principles thinking, tight feedback loops and relentless experimentation

Work Alongside Industry Leaders

Diego Protas – Director of Engineering

Diego, an expert in distributed systems and hardware architecture, merging physical computing with enterprise-scale infrastructure. Previously directing teams of 170+ engineers at Mercado Libre and orchestrating large-scale ML-based inference at Meta. At Relay, Diego’s infectious enthusiasm and hands-on leadership are redefining the boundaries of speed and reliability.

Tech Stack Highlights

• Cross-platform Flutter apps with a deep focus on user experience
• Python, Rust and TypeScript - we keep things simple but use the right tool for the job
• Cloud-native on GCP with extensive use of BigQuery and Cloud Run
• Extensive use of ML modelling and LLM inference - no gimmicks here, this is our daily routine
• Emerging tech integrations, including robotics and IoT-powered operations

What you'll do

• Work across the full stack of technology, from mobile all the way down through data infrastructure.
• Take end-to-end ownership over thorny real-world problems, like using machine vision to automatically assess proof of delivery photos.
• Collaborate with team members across the company.
• Regularly spend time in the field learning how the technology you build impacts our couriers and parcel recipients.

Fast and Focused Hiring Process

1. Talent Acquisition Interview - 30 min
2. Build a UI Component Interview - 1 hour
3. Design and Mobile Fundamentals Interview + AI Programming (Build an APP) - 2 hours
4. Operating Principles & Impact - 1 hour
5. Decision and offer within 48 hours, our process mirrors our pace of work, typically completed in a week.

Who Thrives at Relay?

• Aim with Precision: You define problems clearly and measure your impact meticulously.
• Play to Win: You chase bold bets, tackle the hard stuff, and view constraints as fuel, not friction.
• 1% Better Every Day: You believe that small, consistent improvements lead to exponential growth. You move quickly, deliver results, and learn from every experience.
• All In, All the Time: You show up and step up. You take ownership from start to finish and do what it takes to deliver when it counts.
• People-Powered Greatness: You invest in your teammates. You give and receive feedback with care and candour. You build trust through high standards and shared success.
• Grow the Whole Pie: You seek out win-win solutions for merchants, couriers, and our customers, because when they thrive, so do we.

• If these resonate, and you combine strong technical fundamentals with entrepreneurial drive, let’s connect.
• Relay is an equal-opportunity employer committed to diversity, inclusion, and fostering a workplace where everyone thrives.