Machine Learning Research Engineer Internship at Perplexity (Berlin)

Job Description

Perplexity is offering a machine learning research engineer internship in Berlin, running 12 to 24 weeks full-time in the office, to improve search quality through retrieval and ranking models, representation learning research and retrieval-augmented generation pipelines.

At a glance

• Role: Internship, Machine Learning Research Engineer
• Where: Berlin, Germany (in person)
• Length: 12–24 weeks, full-time
• Focus: retrieval, ranking and representation learning for AI search
• Apply: open until filled (re-checked 12 October 2026)

About the ML research internship

• Push search quality forward through models, data, tools or any other lever available
• Train and optimise large deep learning models in PyTorch using distributed training (such as PyTorch Distributed, DeepSpeed or FSDP), with a focus on retrieval and ranking
• Research representation learning, including contrastive, multilingual and multimodal modelling and evaluation for search
• Build and optimise RAG pipelines for grounding and answer generation

Modern AI search depends on retrieval and ranking models that decide which documents an answer is built from. Better representations, especially across languages and media, make answers more accurate and better grounded, which is why this internship combines research with hands-on model training.

What Perplexity is looking for

• Understanding of search and retrieval systems, including quality evaluation principles and metrics
• Strong PyTorch, with experience in distributed training and performance optimisation for large models
• Interest in representation learning: contrastive learning, dense and sparse representations, fusion, cross-lingual alignment, training data optimisation and robust evaluation
• A publication record at AI/ML conferences or workshops such as NeurIPS, ICML, ICLR, ACL, EMNLP or SIGIR

Pay and location

Perplexity’s posting does not state intern pay. The internship is in person in Berlin for 12 to 24 weeks.

How to apply

Apply through the official Perplexity job posting. Perplexity’s posting does not give a closing date, so the role is open until filled; ResearchJobs.in will re-check this listing on 12 October 2026. Check the posting for location and work-authorisation details before you apply.

See all our artificial intelligence jobs, or browse more research jobs on ResearchJobs.in.