Fullstack Developer (Mid+/Senior)

About Momentum:

At Momentum, we accelerate digital innovation in healthcare. Our mission is to empower HealthTech startups and scaleups by transforming ideas into cutting-edge digital products. We combine deep industry expertise, strategic consulting, and full-stack development to create solutions that drive growth, compliance, and patient impact.

We believe in technology that makes healthcare more accessible, efficient, and human-centered.

About the project

‍An education-sector client is modernizing its existing platform and building new AI-based solutions. We are recruiting several people across two independent roles described below.

Scope

‍An existing platform is entering a deep rebuild: a new React module is being created and the ExtJS layer is being extended. Stack: .NET / .NET Core (C#), Sencha ExtJS and React, with MS SQL Server on the data side. You will build the new React module and extend the ExtJS modules, migrate the client layer from ExtJS 4.x to ExtJS 7.x + React, work in the MVC/MVVM server layer, and keep data access in MS SQL Server efficient on large volumes.

‍Requirements

• Mid+/senior experience as a fullstack developer.
• .NET / .NET Core (C#), MVC/MVVM.
• React in production.
• Exposure to several frontend frameworks (Angular, React, Vue, or similar) and readiness to work with Sencha ExtJS. We do not need an ExtJS expert, rather someone who will get up to speed with it quickly.
• MS SQL Server: experience with large datasets and awareness of how higher-layer decisions affect database performance and cost.
• Git (the project also uses SVN).
• Polish at C1 level (public-sector domain, documentation and communication in Polish).

Nice to have

• Hands-on Sencha ExtJS (4.x and 7.x).
• WebAssembly.
• Experience with accounting-adjacent systems, ERP, or the public sector (subsidies, public procurement).
• SSO and digital content licensing.
• Legacy system migrations.
• English at B2 level.

Recruitment process

‍A short, focused process, the same for both roles:

1. Screening and technical interview on Momentum'w side.
2. Technical interview with the client.

Questions? Get in touch.