Middle Full-Stack Software Engineer (.NET + React)

About us :
Techstack is a technology product engineering company that sets an example for high development standards in the IT industry. We empower each team member to influence the development of the product, company, and processes.
About the product :
We are looking for a Middle Full-Stack Engineer (.NET + React) to join a project for our US-based partner, a digital healthcare company providing remote cardiac monitoring solutions for clinics and hospitals.
The engineer will work on a web-based application that enables healthcare professionals to manage patient monitoring studies and access clinical information. You’ll contribute to both the .NET backend and React-based frontend, developing new functionality, improving existing features, and supporting the security, reliability, and scalability of the product.
Your team :
You’ll join a cross-functional team of .NET developers, QA engineers, an Automation QA Engineer, and a Team Lead. You’ll work closely with the team on developing and improving the product.
Core technology stack:
Backend: C#, .NET, ASP.NET Core, Entity Framework Core
Frontend: React, JavaScript, HTML5, CSS3
Architecture & data: REST APIs, microservices, MS SQL Server, PostgreSQL
Integration & security: AWS SQS; RabbitMQ/Kafka; OIDC, SSO, API security
Cloud & delivery: AWS (ECS, Fargate, EC2, Lambda, S3), Docker, CI/CD
Your responsibilities:
Develop and maintain features across .NET backend services and a React-based web interface.
Build reusable UI components and integrate them with REST APIs.
Develop and maintain REST APIs, integration services, and scalable, stateless backend components.
Work with MS SQL Server, PostgreSQL, and Entity Framework Core.
Implement and support asynchronous service communication using message queues such as AWS SQS, RabbitMQ, or Kafka.
Apply secure development practices, including authentication/authorization, OIDC/SSO, and API security.
Work with AWS-hosted services and support Docker-based deployments and CI/CD pipelines.
Investigate and resolve issues across the frontend and backend.
Participate in code reviews and technical discussions.
Collaborate with developers, QA engineers, and project stakeholders.
Maintain relevant technical documentation.
Contribute to the security, reliability, scalability, and maintainability of the application.
It's about you:
3+ years of professional experience with C# and .NET
Strong practical experience with ASP.NET Core, REST APIs, Entity Framework Core, and microservices
Hands-on commercial experience with React and JavaScript

Flexible work format — remote work or one of our hubs in Kyiv, Lviv, Kharkiv, or Wrocław, plus flexible working hours.
Professional growth — Tech Guilds, mentoring, meetups, knowledge sharing, and other development opportunities.
Education support — 50% compensation for professional courses, trainings, webinars, and certifications.
English — free General English, Business English, and speaking clubs.
Time off — 20 paid days off and 7 paid sick days per year, plus additional days off.
Support — legal and accounting support.
Community — online and offline team activities, professional events, and appreciation gifts.
See yourself in this role? Send us your resume and let’s start the conversation!