LLM Infrastructure Engineer — Production-Scale

Prosus; Amsterdam; Hybrid; EUR 90,000 - 130,000; Full time

Benefits offered by this job

Hybrid work model (Amsterdam)

Competitive compensation

Top-spec MacBook Pro

Job summary

Prosus is seeking an experienced Machine Learning Engineer to develop domain-specific language models. You will own the full training pipeline from continued pre-training to fine-tuning on proprietary data and implement post-training methods.

You will build scalable distributed training infra and drive production-grade code in a fast-paced environment. You will work in Amsterdam hybrid setup, collaborating with teams across ecommerce, fintech, and AI initiatives, delivering high-impact AI

Qualifications

• 3+ years of ML engineering experience.
• Proven experience training and deploying language models to production.
• Experience preparing large-scale training datasets.
• Hands-on experience with distributed training frameworks.
• Strong understanding of training dynamics at scale.
• Expert Python and PyTorch with production experience using Transformers, DeepSpeed, Accelerate.
• Strong software engineering practices: version control, testing, CI/CD, code review.

Responsibilities

• Analyze model performance and training data to identify improvement opportunities and formulate hypotheses for enhancement.
• Design, execute, and rigorously evaluate experiments to improve model quality and training efficiency.
• Train large language models for domain through continued pre-training and fine-tuning on proprietary datasets.
• Design and implement post-training pipelines using RLHF, DPO, GRPO, and other reinforcement learning techniques.
• Build and optimize distributed training infrastructure across multi-node GPU clusters.
• Own large-scale data preparation: filtering, quality assessment, deduplication, and data mixture strategies.
• Generate and curate high-quality synthetic data for instruction fine-tuning.
• Debug training stability issues and monitor model performance during long-running distributed jobs.
• Implement techniques from recent papers and adapt to use cases.
• Build robust evaluation frameworks to measure model quality.
• Write production-grade, well-tested code and contribute to engineering standards.

Skills

3+ years ML engineering

Training language models

Distributed training

Python

PyTorch

Transformers

DeepSpeed

CI/CD

Version control

Code review

Tools

DeepSpeed

FSDP

Megatron-LM

Axolotl

Job description

Prosus is seeking an experienced Machine Learning Engineer to develop domain-specific language models. You will own the full training pipeline from continued pre-training to fine-tuning on proprietary data and implement post-training methods.

You will build scalable distributed training infra and drive production-grade code in a fast-paced environment. You will work in Amsterdam hybrid setup, collaborating with teams across ecommerce, fintech, and AI initiatives, delivering high-impact AI