Full-Stack Developer

Psi CRO; Województwo mazowieckie; On-site; PLN 180,000 - 240,000; Full time

Job summary

Milestone One seeks a Full-Stack Developer to design, build, and maintain internal platforms and integrations. The stack centers on a React/TypeScript frontend with a .NET/C# backend, hosted on Azure and integrated with Microsoft 365.

You will work in a small team, prioritizing secure, data-driven delivery and clear technical documentation. You will model data in Azure SQL, create secure REST APIs, and connect front-end components to internal systems.

Qualifications

• Experience building web apps with React/TypeScript.
• Backend experience in C#/NET.
• Data modeling and Azure SQL experience.
• Fluent English, written and spoken.
• Comfort working in regulated environments.

Responsibilities

• Design and document data models for central data platform (Azure SQL).
• Develop secure REST APIs and backend services (.NET/C#) with proper access checks.
• Build React/TypeScript front ends integrated with intranet and design system.
• Create integrations between internal systems and third-party services (APIs, webhooks).
• Collaborate with stakeholders to shape requirements into solutions.
• Write automated tests (Playwright) and support acceptance testing.

Skills

React/TypeScript

C#/NET

Azure

SQL

REST API design

GitHub Actions CI/CD

Tools

Azure App Service

Azure Functions

Azure SQL

Key Vault

OpenTofu

Playwright

GitHub

Job description

Milestone One is a Site Enabling Services organization with global headquarters in Zug, Switzerland. We understand what clinical study sites need and our overall mission is to support sites in stronger study delivery.

The Full-Stack Developer will design, build, and maintain the internal platforms, applications, and integrations that run Milestone One’s business. Our applications have a React/TypeScript front end, an API layer, and a database backend, hosted on Azure and integrated with Microsoft 365. We work data-first: we design and document the data structure, build the API from that specification, and then build the front end. You will work in a small team alongside AI coding agents, with security, data protection, and documented testing built into how we deliver.

Role responsibilities:

• Design and document data models and databases (Azure SQL) for our central data platform, internal applications, and reporting
• Develop secure REST APIs and backend services (.NET / C#, Azure App Service or Functions), with access checks in the API and permissions enforced at both the API and data layers
• Build React/TypeScript front ends that integrate with our company intranet and follow the Milestone One design system
• Build integrations between internal systems and third-party services (APIs, webhooks, data imports)
• Work in GitHub: pull requests, code reviews, GitHub Actions CI/CD, and automated code and secret scanning
• Define infrastructure as code with OpenTofu, using Managed Identity and Key Vault instead of stored secrets
• Write automated tests with Playwright and support business users during acceptance testing
• Use AI coding agents productively and safely, reviewing, testing, and taking ownership of all generated code
• Follow our change management and system validation procedures, and keep technical documentation current
• Collaborate with stakeholders to shape requirements and turn them into working solutions
• Professional experience building web applications with React/TypeScript and a backend language such as C# / .NET (we welcome both experienced and early-career developers)
• SQL — schema design, data modelling, and writing efficient queries
• REST API design, authentication and authorization (Entra ID, OAuth 2.0 / OpenID Connect)
• Git branching, pull requests, and code review; CI/CD pipelines (GitHub Actions or Azure DevOps)
• Azure fundamentals — App Service, Azure SQL, Blob Storage, Key Vault, Managed Identity
• Secure coding practices (e.g. OWASP Top 10) and care for personal and sensitive data
• Willingness to work in a regulated environment: change control, testing evidence, audit trails, and data integrity
• Fluent in English, written and spoken

Nice to Have

• .NET 8 / C# — REST API development (Entity Framework or Dapper)
• Infrastructure as code with OpenTofu or Terraform
• Automated testing with Playwright or similar tools
• Professional experience working with AI coding agents or assistants
• Azure Functions, Static Web Apps, API Management, Front Door / WAF v2
• Star schema / dimensional modelling (staging dimension fact ETL)
• Microsoft Graph API and Microsoft 365 integration
• Clinical trial domain knowledge (sites, studies, patients, financial events)
• Knowledge of data protection requirements such as GDPR and HIPAA

If you feel it is time to make your skills and knowledge visible within a developing company with true focus on its people, then Milestone One is the right choice for you.