What are the responsibilities and job description for the 2026 PhD Residency - Knowledge Graph, Operations Research and Reinforcement Learning, Early Stage Project position at Loon?
InternshipMountain View, CA
How you will make 10x impact:
General description: A machine learning/artificial intelligence specialist with experience in LLM and reinforcement learning post training.
- Collaborating with the X Project team to design and develop machine learning approaches/algorithms to support the project's mission
- Understanding the project’s goals and challenges and conduct relevant literature surveys
- Suggesting agentic RL solutions in which machines/approaches/algorithms/models can apply to those challenges
- Prototype/train/evaluate RL algorithms, tools and components of large scale AI systems
- Engaging with the resident community during the program, engaging with the X community, attending colloquia and tech talks.
This project aims to push the limits of science and modeling as we know them and to prove how ML can radically accelerate our understanding of the world
- Location: X's headquarters in Mountain View, CA
- Start Date(s): January 2026
- Duration: a flexible full-time 4 mo. to 1 year program based on project team needs and your availability
Throughout your AI Residency you can expect:
- To be embedded into one of our confidential or public X projects
- To get paid competitively and receive benefits
- To be a part of a lively community of AI and ML Residents
- To attend tech-talks with AI leaders from across X
What you should have:
- Currently enrolled in a PhD program in a STEM field such as CS, Physics, Engineering or Mathematics/Statistics with a strong interest in machine learning.
- Strong experience with one or more general purpose programming languages such as Python, C/C .
- Experience with reinforcement learning (RL) and large language models (LLMs).
- Ability to set up RL infrastructure and synthetic data generation pipelines.
- Familiarity with operations research (OR) problems and their formalization.
- Knowledge of basic ontologies and programmatically constructing knowledge graphs (KG) from structured and unstructured data.
It’d be great if you also had these:
- Open-source projects that demonstrate relevant skills and/or publications in relevant conferences and journals (e.g. NeurIPS, ICML, ICLR, CVPR, ICCV, COLM, ACL/EMNLP, ICASSP).
- Experience with GRPO/DAPO based online reinforcement learning with LLMs(7B ) on multi-GPU settings.
- Ability to produce code (e.g., in Google OR-Tools) and define rewards for formalized optimization problems.
- Experience translating natural language into formal graph query languages (Cypher, SPARQL).
- Experience using frontier LLMs (e.g., Gemini-Pro) to generate large-scale, high-quality synthetic datasets with automated verification steps.
Additional public information:
https://www.wired.com/video/watch/astro-teller-captain-of-moonshots-at-x-speaks-at-wired25
https://www.bloomberg.com/news/videos/2019-10-10/alphabet-x-s-astro-teller-on-bloomberg-studio-1-0-video
An Equal Opportunity Workplace
At X, we don't just accept difference - we celebrate it, we support it, and we thrive on it for the benefit of our employees, our products and our community. We are proud to be an equal opportunity workplace and is an affirmative action employer. We are committed to equal employment opportunity regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity or Veteran status. We also consider qualified applicants regardless of criminal histories, consistent with legal requirements.
If you have a disability or special need that requires accommodation, please contact us at x-accommodation-request@x.team.