Qualifications

• 3+ years of experience in C# / . NET / ASP. NET Core with a proven ability to create and launch production backend services.• Strong expertise in RESTful API design, ensuring ease of use and maintainability.• Comprehensive database knowledge, focusing on schema design and performance tuning.• A proactive approach to security and reliability in coding practices.• Previous experience with high-availability systems is highly valued.

About the job

Pristina, Kosovo · In-Office

Sent develops unified messaging APIs that enable businesses to reach customers on platforms like SMS, WhatsApp, iMessage, and RCS. With $5.8M in funding, the company supports developers who send millions of messages daily.

Role overview

The Backend Engineer (. NET) will design, build, and maintain the core backend services behind Sent’s messaging platform. This role centers on developing APIs and backend systems that thousands of developers rely on for multi-channel communication.

What you will do

Develop and maintain RESTful APIs and backend services using C#, . NET, and ASP. NET Core for Sent’s messaging platform.
Write clean, efficient, and scalable code to support high message volumes across multiple channels.
Monitor and improve system reliability, taking responsibility for uptime and performance. Respond quickly to issues as they arise.
Integrate the platform with carrier networks, third-party services, and internal systems. Collaborate with frontend and DevOps teams to deliver complete features.
Identify and resolve performance bottlenecks, optimize queries, and refine database schemas as the product evolves.
Participate in architectural discussions and contribute to designing secure, scalable backend systems.

Requirements

Minimum 3 years of experience with C#, . NET, and ASP. NET Core, building production-ready backend services.
Strong experience designing RESTful APIs, including versioning and developer usability.
Solid foundation in relational databases: schema design, query optimization, and ensuring data integrity.
Emphasis on security and reliability, including authentication, authorization, and planning for failure scenarios.
Experience with high-availability systems is a plus, especially if you have maintained uptime in production environments.

Why join Sent?

Sent values craftsmanship, open communication, and meaningful results. Work on technical challenges at the core of messaging infrastructure and help shape how businesses connect with their customers.

Backend Engineer (.NET)

Experience Level