Senior Software Engineer - Lead on Large-Scale SaaS (Hybrid)

Aon plc; Polska; Hybrid; PLN 120,000 - 180,000; Full time

Job summary

Aon plc in Poland is seeking a Senior Software Engineer to take ownership of building and delivering major features for a large-scale platform. You will work across the full development lifecycle, collaborating with global teams to ship high-quality software.

The role is hybrid in Poland with flexible remote and office options under the local policy. You will mentor peers, review code, and apply modern engineering practices, including AI-assisted development.

Qualifications

• 4+ years of professional software engineering experience, ideally in large-scale SaaS or enterprise apps.
• Strong hands-on experience with C#, .NET, SQL and JavaScript; independently develop and deliver complex features.
• Strong understanding of database design, SQL querying, schema design and optimization; API and system integrations experience.
• Experience with code reviews, automated quality checks and software building; consider maintainability, performance and broader consequences of decisions.
• Strong analytical, communication and collaboration skills; ability to work with global teams and mentor less experienced engineers.
• Experience with MVC, React, Azure, AKS/Kubernetes, Azure DevOps CI/CD, OpenAPI; mentoring engineers; automated testing frameworks or HR tech platforms advantageous.

Responsibilities

• Developing and delivering complex components and subsystems using C#, .NET, SQL, JavaScript and React, with a focus on clean, maintainable and well-tested code.
• Translating product requirements into clear implementation plans and contributing to technical specification documents alongside the Team Lead.
• Conducting code reviews and supporting strong engineering practices across software architecture, APIs, automated testing and CI/CD.
• Investigating complex technical and production issues, while considering performance, security, accessibility and the wider impact of changes across the platform.
• Working closely with the Team Lead, Solution Architects, QA and Business Analysts to clarify requirements, validate technical designs and manage dependencies across teams.
• Supporting engineers with less experience through code reviews, pairing and technical mentorship, while using AI tools in day-to-day engineering work including building, coding, testing and documentation.

Skills

4+ years exp

C#, .NET, SQL, JavaScript

Database design & SQL optimization

Code reviews & CI/CD

Mentorship & collaboration

MVC, React, Azure, Kubernetes

OpenAPI & HR tech

Tools

MVC, React, Azure, AKS/Kubernetes

Azure DevOps CI/CD

OpenAPI

Job description

Aon plc in Poland is seeking a Senior Software Engineer to take ownership of building and delivering major features for a large-scale platform. You will work across the full development lifecycle, collaborating with global teams to ship high-quality software.

The role is hybrid in Poland with flexible remote and office options under the local policy. You will mentor peers, review code, and apply modern engineering practices, including AI-assisted development.