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June 30, 2026

Senior Backend/Fullstack Developer

Senior • Remote

Lisbon, Portugal

Summary

The role of Senior Backend/Fullstack Developer is crucial for the evolution of an enterprise application that aids municipalities in managing waste collection and environmental services. This role focuses on solving complex technical problems and improving existing software rather than just creating new applications.

Responsibilities

  • Develop and maintain a large-scale enterprise application built with C# and .NET.
  • Troubleshoot and resolve complex production issues across the platform.
  • Analyse existing solutions and improve maintainability through refactoring.
  • Improve application performance and optimise database queries.
  • Develop backend services and REST APIs.
  • Work with PostgreSQL using both raw SQL and Entity Framework.
  • Contribute to architecture discussions and technical decision-making.
  • Write clean, maintainable and well-tested code.
  • Implement Unit Tests and Integration Tests.
  • Participate actively in Scrum ceremonies, refinement sessions and technical discussions.
  • Contribute to continuous improvement initiatives across the development lifecycle.
  • Help identify opportunities to leverage AI-assisted software development tools to improve engineering efficiency.

Key Requirements

  • 8+ years of professional software development experience.
  • Strong experience with C# and .NET (both .NET Framework and modern .NET).
  • Solid understanding of enterprise backend development.
  • Extensive experience debugging complex production systems.
  • Experience working with legacy and monolithic applications.
  • Strong SQL skills, including writing, analysing and optimising raw SQL queries.
  • Experience with PostgreSQL or other relational databases.
  • Experience using Entity Framework or similar ORM technologies.
  • Experience designing and consuming REST APIs.
  • Experience with Git, GitHub and CI/CD pipelines.
  • Experience writing Unit Tests and Integration Tests.
  • Good understanding of Agile methodologies (Scrum).
  • Ability to work independently and proactively.
  • Excellent English communication skills.

Nice to Have

  • Experience with waste management systems.
  • Experience in public sector software.
  • Knowledge of utilities or environmental platforms.
  • Understanding of SOLID principles.
  • Experience in software architecture.
  • Skills in performance optimisation.
  • Familiarity with security best practices.
  • Knowledge of domain-driven design.
  • Experience with GitHub Copilot and AI-assisted software development.
  • Understanding of process optimisation.
  • Experience in technical mentoring.

Other Details

Technical Environment:

  • C#
  • .NET
  • ASP.NET
  • PostgreSQL
  • REST APIs
  • Git/GitHub
  • CI/CD

Initial Onboarding

In the first three months, the developer will learn the RenoWeb platform, work independently on bug fixes, and deliver small tasks, with expectations of becoming largely autonomous by the end of the onboarding period.

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