Senior Software Developer (.NET + React)

October 18, 2026

Hybrid

Senior

Warsaw, Poland

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English is required

Description

A leading European full-service railcar lessor is growing its organization and hiring a Senior Software Developer to design, develop and operate a modern cloud-based ERP solution. The role spans frontend, backend and infrastructure with a strong focus on software quality, automation, scalability and operational excellence. The developer works closely with the .NET Technical Lead and international cross-functional teams on architecture decisions, reliable CI/CD and production support.

Responsibilities

Design, develop, and maintain frontend, backend, and infrastructure code of a cloud-based ERP solution
Contribute to solution architecture and technical design with a focus on scalability, maintainability, and performance
Implement data replication mechanisms, messaging patterns, and integrations across systems
Design, maintain, and optimize relational database schemas, queries, and migrations
Build, operate, and enhance CI/CD pipelines, Docker images, and Terraform-based infrastructure
Ensure high software quality through automated testing, code reviews, and adherence to best practices
Monitor, troubleshoot, and support production systems; contribute to observability and incident resolution
Collaborate with international, cross-functional teams to ensure end-to-end process integration and documentation

Requirements

5+ years of experience as a full-stack software developer in international projects
Strong proficiency in C# / .NET (8+), ASP.NET Core Web APIs, and Entity Framework Core
Solid frontend expertise with React, TypeScript, and modern build tools (e.g. Nx, Vite, pnpm)
Experience designing and optimizing relational databases (PostgreSQL or equivalent)
Hands-on experience with AWS and cloud-native architectures (compute, networking, security, observability)
Strong DevOps mindset with experience in Docker, Terraform, and CI/CD pipelines (e.g. GitHub Actions)
Experience with automated testing (unit, integration, API, and/or E2E testing)
Strong analytical mindset with the ability to understand, decompose, and solve complex business and technical problems
Ability to translate business requirements into robust technical solutions
Fluency in English
Experience with Azure AD / Entra ID, OData, Redis, or OpenTelemetry
Exposure to AWS multi-account setups, hybrid/on-prem integrations, or ERP systems
Familiarity with Jira, Confluence, and agile development methodologies

Conditions

Full-time employment
Attractive and well equipped workplace in the heart of the city center
Interesting job where you can meet diversified challenges and tasks every day
International working environment, shaped by team work and a great atmosphere
Appropriate remuneration and social benefits of a modern company
Flexible working time including home office model
Close cooperation and exchange of experience with other skilled teams within the group
Opportunity for professional development with wide range of trainings