Telness Tech is on a mission to simplify and digitize the telecom industry. Our platform powers next-generation mobile providers, from traditional MVNOs to eSIM challengers and non-telecom brands embedding connectivity. With our roots in Stockholm and global ambitions, we’re building the future of telecom: fast, flexible, and customer-first.

As we enter a phase of international growth, we're looking for a Senior Software Engineer with a talent for real-time communication to help us become the global leader in #teltech!

About the role

You'll be part of Team Calling, a cross-functional team of skilled engineers responsible for our call-handling functionalities, including switchboards, desktop softphones, mobile apps, and related infrastructure.

Our backend is built in Golang and runs in AWS using Kubernetes. Communication between backend services uses gRPC, and the front end uses React. We use GraphQL and REST, and primarily use PostgreSQL databases with event sourcing.

We're scaling up our platform to new markets with dynamic requirements, and you'll play a crucial role in shaping, designing, and building fundamental components. As the company expands, you'll help us tackle new and interesting challenges, scaling our platform from tens of thousands to hundreds of millions of users.

About you

You're an experienced Sr. Software Engineer who has likely worked at several companies, including at least one startup where you contributed from an early stage of growth. You have experience working with real-time communication/SIP in a full-stack role and are comfortable diving into occasional front-end work with React. You're excited about joining a startup journey where you'll shape both product and technology while working in a small, high-autonomy team.

What we look for

• 5+ years as a backend/full-stack engineer in a modern tech environment, focusing on real-time communication solutions/SIP (softphones, streaming, etc.)
• Proven ability to solve complex technical problems in a collaborative team environment
• Passion for technology and excitement for the challenges of adapting tools and workflows to support our scaling journey
• Ownership mindset—invested in your growth and that of your teammates, with a willingness to learn and share knowledge
• Drive to improve technical systems and processes, motivated to implement positive changes that benefit both the team and the company
• Self-motivated, autonomous, and energized by new challenges
• Excellent verbal and written communication skills, with high proficiency in English

Why Telness Tech?

We’re not building for telco as it is; we’re building for how it should be: fast-moving, easy to use, and built for the people who use it. At Telness Tech, you’ll join a curious, ambitious, and transparent team. We work hard, we move fast, and we support each other every step of the way.

Here’s what you can expect:

• Join an ambitious, well-funded startup entering a dynamic phase of global growth
• Play an active role in building one of the telecom industry’s most innovative companies
• A high-trust, high-autonomy environment where you’ll be encouraged to take ownership and explore growth opportunities for both Telness Tech and your development
• A friendly, positive, and supportive workplace that fosters collaboration and constructive challenge
• Complimentary daily breakfast, regular "Friday" AWs, and fun activities!
• Hybrid/remote work setup with an office in central Stockholm

Sounds like your challenge? We’d love to hear from you.

Currently, we're not able to offer relocation or visa sponsorship.