Senior Machine Learning Engineer @ Zalando SE
BERLIN, DE- Architected a two-tower neural retrieval system serving 50M+ active users across 25 markets, replacing lexical BM25 baselines and lifting session GMV by +3.4% (p < 0.001) at 14ms p99 latency.
- Led INT8/FP16 post-training quantization and custom TensorRT/Triton execution pipelines for transformer re-rankers, cutting GPU fleet provisioning costs by 41% across 120× A10G nodes with zero NDCG@10 degradation.
- Built an automated counterfactual off-policy evaluation framework (Doubly Robust & clipped IPS estimators) over logged impression streams, shrinking candidate ranking validation cycles from 3 weeks to 48 hours.