Senior Back End Developer

elockers; Amsterdam; On-site; EUR 60,000 - 90,000; Full time

Benefits offered by this job

Gross salary €60k-€90k/year

Job summary

elockers is seeking a highly capable Senior Back-end Developer to strengthen a real-time payments and hardware-integrated platform. You will design and implement complex distributed systems, focusing on Node.js and microservices within a cloud-native setup.

You'll work hands-on, not as a manager, tackling live event-scale reliability and API integrations with Adyen and hardware locks across multiple countries.

Qualifications

• Independent, hands-on senior backend developer capable of designing and debugging distributed systems.
• Strong Node.js and microservices expertise with a focus on payments and hardware integration.
• Clear communicator who thrives in a small, fast-moving team.

Responsibilities

• Design, build, and debug complex microservices in a real-time payments platform.
• Integrate software with Adyen-based payments and IoT hardware components.
• Maintain CI/CD, documentation, and robust production reliability.

Skills

Node.js

Microservices

Distributed systems

Cloud engineering

Payments integration

IoT integration

React Native/Expo

Tools

DigitalOcean App Platform

Kafka

ClickHouse

Metabase

Sentry

New Relic

Jira

Job description

Elockers runs the smart-locker platform that festivals, venues, and events across six countries rely on for real-time payments and marketplace-style payouts, including on-sale moments where a large share of a site's lockers can sell out within a minute. We're live in eleven countries, with further international expansion underway.

Our platform is genuinely strong: microservices architecture (~30 services), event-driven data flow, and a payments stack built for a real marketplace. This isn't a role about fixing something broken. It's about strengthening a platform that already works well, hands-on.

The Role

We're looking for an exceptionally strong, hands-on Senior Back-end Developer to work deep in our microservices platform, where software, payments, and physical hardware come together. You'll match our current technical level and raise it through your own hands-on work. This is a pure individual-contributor role: you'll design, build, and debug complex systems yourself, with real technical depth, not people management.

What you'll work on

• Our microservices platform, with Node.js and modern architecture patterns at the core
• Cloud-native engineering on DigitalOcean App Platform: deployment, scaling, monitoring, and production reliability
• Reliability at peak: real-time payments and traffic spikes during live events, with zero tolerance for downtime
• Our Adyen-based payments and marketplace systems, and how our software connects to physical locks and hardware
• Engineering discipline: CI/CD, documentation, and AI-assisted development, as we raise an already-strong platform further

What you'll bring

• Deep, hands-on technical seniority. You independently design, build, and debug complex distributed systems
• Strong, current Node.js and microservices expertise, a core requirement
• Real soft skills and team fit. A clear communicator who works well in a small, fast-moving team
• Genuine ownership mentality. You step up when something business‑critical is on the line
• Cloud/platform engineering experience, ideally DigitalOcean App Platform
• Payments or marketplace experience (Adyen, PSPs, split payments, KYC) and comfort with high‑peak, mission‑critical systems
• IoT/hardware integration experience is a genuine plus, our software talks to physical lockers
• Nice to have: React Native/Expo experience, multi‑country scaling with GDPR awareness, background in events or ticketing

Our stack today

Microservices (~30 services), moving toward Node.js at the core. Adyen for payments. Kafka, ClickHouse, Metabase for data. React Native/Expo for mobile. DigitalOcean, Sentry, New Relic, Jira for infra and tooling.

What we offer

• A gross annual salary of €60,000-€90,000, depending on experience
• Real technical depth, working on a platform where software, payments, and hardware genuinely come together

For questions feel free to contact Brendan @ 0615348554 or [e-mail]