AI Engineer/Developer

Appsierra Group; Brussel Hoofdstad; Sur place; EUR 90 000 - 130 000; Plein temps

Résumé du poste

Appsierra Group is seeking an AI Engineer/Developer for its Brussels location. You will design and implement AI-powered applications using LLMs, RAG, and agentic workflows, build backend services and APIs, and craft robust retrieval pipelines with embeddings and vector search.

You will ensure observability, security, and scalable production readiness while collaborating with cross-functional teams. Fluent English and French or Dutch are required, with 5+ years in software engineering and 1–2

Qualifications

• You fluently speak English and French or Dutch.
• Minimum 5 years as Software Engineer, backend or full-stack.
• 1–2 years integrating LLMs or generative AI into apps.
• Hands-on with RAG, embeddings, vector search, and retrieval quality.
• Strong Python programming skills.
• Experience with MCP, A2A, tool calling or multi-agent workflows.
• Experience building maintainable services with tests, logging, CI/CD.
• Understanding AI evaluation including datasets and metrics.

Responsabilités

• Design and implement AI-powered apps using LLMs, RAG, and agentic workflows.
• Build backend services, APIs, and integrations for AI-centric apps.
• Design and improve retrieval pipelines including embeddings and vector search.
• Work with LLM APIs and orchestration frameworks to create reliable workflows.
• Implement evaluation, testing, monitoring, and observability for AI apps.
• Define safe patterns for tool use, human-in-the-loop approvals, and agent behavior.
• Collaborate with other engineers and product/business stakeholders.
• Support model/framework selection based on quality, cost, latency and security.
• Troubleshoot hallucinations, retrieval quality, latency and cost issues.

Connaissances

Python

LLMs

RAG

Vector search

CI/CD

Observability

Security

Cloud-native

Multi-agent workflows

English/French/Dutch communication

Outils

LangGraph

LangChain

Semantic Kernel

Azure

Microsoft Foundry

.NET/C#

Vector databases

Description du poste

Role: AI Engineer/Developer

Location: brussels BE

Langugae: French/Dutch

1. Design and implement AI-powered applications using LLMs, RAG, and agentic workflow patterns.


2. Build backend services, APIs, and integrations needed for AI-centric applications.


3. Design and improve retrieval pipelines, including chunking, embeddings, vector search, hybrid search, metadata filtering, and reranking.


4. Work with LLM APIs and AI orchestration frameworks to build reliable workflows.


5. Implement evaluation, testing, monitoring, and observability for AI applications.


6. Help define safe and practical patterns for tool use, human-in-the-loop approval, and agentic behavior.


7. Collaborate with other engineers and product/business stakeholders.


8. Support model and framework selection based on quality, cost, latency, maintainability, and security.


9. Help troubleshoot issues such as hallucinations, poor retrieval quality, high latency, cost inefficiency, and unreliable outputs.

Requirements

• You are able to speak, read and write fluently English and French or Dutch.


• Minimum 5 years of experience as Software Engineer, preferably in backend or full-stack development.


• Minimum 1 to 2 years of experience integrating LLMs or other generative AI services into software applications.


• Practical knowledge of RAG, embeddings, vector search, and retrieval quality improvement.


• Strong programming skills in Python.


• Experience with MCP, A2A, tool calling, or multi-agent workflows.


• Experience designing maintainable services with proper testing, logging, CI/CD, and deployment practices.


• Understanding of AI application evaluation, including test datasets, quality metrics, regression testing, and user feedback.


• Good understanding of cloud-native application development.


• Security-conscious mindset when working with internal or sensitive data.


• Ability to communicate technical trade-offs clearly and pragmatically.


• Ability to distinguish when AI, RAG, or agents are useful and when a simpler deterministic solution is better.


• Nice to Have


• Experience with AI frameworks such as LangGraph, LangChain, Semantic Kernel.


• Experience with observability or evaluation tools.


• Familiarity with Azure cloud environment.


• Experience with Microsoft AI ecosystem tools such as Semantic Kernel, Microsoft


• Agent Framework, Microsoft Foundry, or Microsoft 365 Agents SDK.


• Experience with .NET / C#.


• Experience with vector databases or enterprise search platforms.


• Experience working in regulated, security-sensitive, or enterprise environments.


• The right consultant should be comfortable working across software engineering, AI integration, evaluation, security, and production readiness. They should be able to move fast when building MVPs, while still applying enough engineering discipline to make successful solutions scalable and maintainable.