Senior Developer / Tech Lead

ThoughtLabs Belgium; Brussel Hoofdstad; On-site; EUR 90,000 - 130,000; Full time

Job summary

ThoughtLabs Belgium is seeking a Senior Developer / Tech Lead to drive architecture, code quality, and delivery of complex software using .NET and Azure. You will set coding standards, mentor developers, and ensure quality across projects.

You will translate business needs into technical specs, oversee reviews, and guide a scalable platform while collaborating with cross-functional teams. Dutch is a must; English and French are nice to have.

Qualifications

• Azure cloud services and structure
• .NET application development
• CI/CD, containers, DevOps culture
• Frontend knowledge with Angular

Responsibilities

• Set the technical standard: oversee code quality, reviews, and coach developers
• Translate business and domain requirements into technical analyses and specs
• Contribute to scalable .NET/Azure platform development
• Oversee architecture, security, and QA in an AI-native environment

Skills

Azure

.NET

DevOps

Kubernetes

Docker

Angular

AI coding tools

Tech lead

Tools

Marten

GraphQL

PostgreSQL

RabbitMQ

MassTransit

Elasticsearch

AZ-204

AZ-400

Job description

Role Title: Senior Developer / Tech Lead.

Start Date: ASP

About the job

We are looking for an experienced Senior Developer / Tech Lead. In this role, you will work on challenging projects using the latest technologies and serve as a key link in the development and optimization of our software products.

What will you be doing?

• You set the technical standard: you oversee code quality, conduct reviews, and provide technical coaching to developers.
• You translate business and domain requirements into clear technical analyses and specifications.
• You contribute to the development of a scalable business platform based on .NET and Azure.
• You work in an AI-native environment. Agents write, test, and refactor code, while you oversee the architecture, security, and quality of their output.

Essential knowledge and experience:

• Azure: Experience with Azure services and cloud-based infrastructures.
• .NET: Thorough knowledge of .NET and experience with application development.
• DevOps, Kubernetes & Docker: Experience with CI/CD pipelines, containerization, and implementing a DevOps culture.
• Angular: Knowledge of frontend development using Angular.
• AI coding tools: Experience with tools such as Claude Code and GitHub Copilot in real-world projects, and the ability to critically evaluate their output.
• Tech lead: Experience with code reviews, technical coaching, and technical analysis.

Desired additional technologies:

• Marten: Experience with Marten for event sourcing and managing document-oriented data in .NET.
• GraphQL: Experience with API design and optimization.
• PostgreSQL: Experience with document databases and SQL.
• RabbitMQ & MassTransit: Experience with message-based systems and event-driven architecture.
• Domain-Driven Design (DDD): Knowledge of and experience applying DDD principles to build scalable and well-structured applications.
• Elasticsearch: Experience implementing and using Elasticsearch for search functionality and data analysis.
• Certifications: AZ-204 and AZ-400 are a nice-to-have.

What are we looking for?

• Problem-solving skills: You have the drive and insight to solve complex problems quickly and efficiently.
• Resilience under pressure: You handle chaos and pressure well without losing focus.
• Proactive: You don't wait around; instead, you think ahead and propose improvements.
• Eagerness to learn: You have a passion for technology and are committed to continuous self-development.
• Team player: You collaborate effectively with other developers but are also capable of working independently. You enjoy sharing knowledge and helping to elevate the team’s technical capabilities.
• Languages: Dutch (must have), English & French (nice to have)