Senior Backend Developer

About Kaizen

Kaizen Loyalty is a fast-growing B2B SaaS company building loyalty and engagement platforms that drive measurable user behavior and business growth.

Operating across Istanbul and London, we work with leading brands such as Anadolu Efes, Ferrero, Nestlé, and Coca-Cola, reaching over 20 million users through our platforms.

What This Role Is

A deeply technical backend engineering role, scalable APIs, event-driven systems, multi-tenant architecture, cloud-native infrastructure.

But it's more than writing great backend code. AI tools are already in use across our team. Your job is to take that further: build the workflows, set the standards, and mentor engineers so that AI-augmented development becomes the norm not the exception.

We're not looking for someone who uses AI well alone. We're looking for someone who makes the whole team better at it.

What You'll Work On

• Designing and building scalable .NET backend services powering loyalty, rewards, and gamification flows
• Evolving our multi-tenant SaaS architecture for performance and maintainability
• Integrating AI-assisted tooling into development workflows; code generation, refactoring, testing, documentation
• Working with event systems (RabbitMQ / Azure Service Bus) and distributed architectures

What We're Looking For

Hard requirements:

• 5-8 years of backend engineering experience in production environments
• Strong hands-on expertise in .NET / C#
• Active daily use of AI development tools (GitHub Copilot, ChatGPT, Cursor, or similar)
• Awareness of AI limitations and hallucinations, you know when to trust the output and when to validate it
• Proven experience with scalable API design and distributed systems
• Solid understanding of SQL (SQL Server preferred), caching (Redis), and ORM tools (EF Core)
• Cloud experience: Azure or AWS (hands-on, not just familiarity)
• CI/CD and DevOps comfort — you've deployed, monitored, debugged in production

Strong plus:

• Experience with multi-tenant SaaS architecture
• LLM API integration (OpenAI, Azure OpenAI)
• Kubernetes / containerized environments
• Messaging systems: Kafka, RabbitMQ, Azure Service Bus
• Experience in loyalty, marketing automation, or engagement platforms

What We Offer

• Opportunity to shape a growing global SaaS platform
• Direct impact on products used by millions of users
• A product-driven engineering culture
• Close collaboration with product, UX and engineering teams
• Ownership-oriented working environment
• Opportunity to work on scalable cloud-native platform systems

What’s in It for You?

🌍 Remote-friendly – Work from anywhere

💰 Competitive salary + performance-based bonus – Your success is rewarded!

🌟 Flexible benefits – Spend it on what fits your lifestyle, whether it’s wellness, sports, or insurance for your furry companion.

📚 Learning & development opportunities – Grow with us.

🎉 A fun, dynamic team – Work with smart, driven people who love what they do.