aimlroles

Internship - Search Machine Learning Engineer

Perplexity perplexity.ai Open · verified Oct 22, 2026
Belgrade Full-time Junior Machine Learning Engineering

At a glance

Junior Machine Learning Engineering role at Perplexity. Belgrade · full-time.

Pay not stated Machine Learning Engineering salary

RoleMachine Learning Engineering
SeniorityJunior
LocationBelgrade
EmploymentFull-time
PostedJan 13, 2026 · 9mo ago
Role brief

aimlroles summary, based on the employer's posting.

What you'll do

  • Improve search quality by testing models, data choices and evaluation methods with guidance from senior engineers
  • Build parts of the search platform for retrieval, ranking and classification
  • Train and assess models, including LLM-based methods, for search and classification tasks
  • Help deploy and monitor search models, and refine RAG pipelines for grounded answers
  • Work with data, AI, infrastructure and product teams to deliver production ML improvements

What you bring

  • A solid grounding in machine learning and statistics, through study or projects involving retrieval, ranking or recommender systems
  • Hands-on Python and experience with a common ML framework such as PyTorch, TensorFlow or another listed option
  • A completed project you took the initiative to build, beyond a class assignment
  • You are enrolled at a Serbian university or are self-taught with a strong interest in software engineering and technology

Who this fits

This internship suits an early-career candidate who wants to learn production machine learning alongside experienced engineers. It is full-time and in person at the Belgrade office, with a program lasting twelve to twenty-four weeks. You should be comfortable working in English and with a fast pace, high standards and direct feedback.

From the employer

Perplexity is looking for a Search Machine Learning Engineer Intern to help build the next generation of advanced search technologies, with a focus on retrieval and ranking. You will work closely with experienced engineers to improve search quality, experiment with new models, and ship features that directly impact how users search and discover information.

Internship program: 12 - 24 weeks, full-time, part-time, in-person in the Belgrade office.

Responsibilities:

  • Contribute to experiments that improve search quality through better models, data usage, and evaluation tools, under the guidance of senior engineers.

  • Design and implement components of the search platform and model stack, including retrieval, ranking, and classification models.

  • Train evaluating models (including LLM-based approaches) for retrieval, ranking, and classification tasks.

  • Support deployment and monitoring of search and ranking models in a scalable and performant way.

  • Help build and iterate on RAG pipelines for grounding and answer generation.

  • Collaborate with Data, AI, Infrastructure and Product teams to deliver improvements quickly and learn best practices in production ML.

Qualifications:

  • Strong foundation in machine learning and statistics, with coursework or projects related to information retrieval, ranking, or recommender systems.

  • Experience with Python and common ML frameworks (e.g. PyTorch, TensorFlow, JAX) through academic, open source, or personal projects.

  • Familiarity with evaluating model quality using offline metrics and/or A/B testing is a plus, but not required.

  • Previous experience (internships, research, or significant projects) working on search, recommendation, or NLP is a plus, but not required.

  • Self-driven and curious, with a strong sense of ownership, willingness to learn, and comfort working in a fast-paced environment

  • Experience with Rust will be a plus

What we're looking for:

  • You’ve built something you’re proud of: Not just a class assignment - we want to see a project you genuinely cared about and took the initiative to build and finish.

  • You’re currently enrolled at a Serbian university: Bachelor’s, Master’s, or PhD program or you’re self-taught with a strong passion for software engineering and technology.

  • You’re curious, persistent, and self-driven: you take ownership, work through challenges, and follow through on what you start.

  • You’re eager to learn and improve: you’re willing to put in the work, develop your skills, and get better every week.

  • You’re comfortable working in English: in a collaborative, professional environment.

  • You thrive in a high-performance environment: you’re comfortable with high standards, direct feedback, and a fast pace.

  • You’re willing to challenge and be challenged: You’re comfortable asking questions, sharing your perspective, and pushing back constructively when it matters.