Senior Software Engineer – Platform & Security Focus

Company: Sitoo (sitoo.com)

Location: Stockholm

Type: Hybrid role, Full-time

Join a highly skilled team of developers shaping the future of retail technology!

Sitoo is a fast-growing technology company exploring how far innovation can go to deliver a world-class Unified Commerce Platform and Point of Sale (POS) solution. Their platform powers physical retail stores, integrating with payment devices, receipt printers, and tablets, and is used across Europe and the UK. With ambitious plans to scale their engineering team, they are looking for a software/platform engineer engineer who can help define and strengthen their platform and security foundations.

About the role

As a Senior Software Engineer with a security focus, you will join a small, agile team building scalable and secure backend services. You will take ownership of core platform components, design AWS architectures, and help shape how security is embedded in development processes. This is an opportunity to influence both technology and culture from the ground up.

What you’ll do

• Build and evolve backend services and APIs that are scalable, observable, and secure.

• Design resilient AWS architectures and manage multi-account setups using Infrastructure as Code.

• Lead authentication and authorization patterns, guiding teams on secure access.

• Set security standards, implement automated guardrails, and help product teams ship safely.

• Collaborate closely with product managers, engineers, and cross-functional teams to drive autonomous, high-quality delivery.

What we’re looking for

• Strong hands-on experience with server-side development and building cloud services in AWS.

• Solid expertise in security best practices, identity and access management, tokens, and federation.

• Experience integrating security controls into CI/CD pipelines.

• Confidence in influencing teams and guiding colleagues on secure development.

• Professional English, both written and spoken.

What makes this role exciting

• You’ll help shape the company’s security approach from scratch.

• You’ll work in a fast-moving, startup-like environment with a strong engineering culture and autonomy over your work.

• The company operates in the fashion and lifestyle retail sector, working on complex, multi-product systems.

• Hybrid work model: mostly remote but occasional collaboration in Stockholm.

• Collaborative culture: weekly social events, a solution-oriented mindset, and strong work-life balance.

This is a chance to have a direct impact on how the company scales securely while working on a cutting-edge retail platform. If you are a senior engineer with a passion for AWS, platform engineering, and security, they would love to hear from you.

For more information or questions, contact zoe.lepluart@ninox-limited.com.