Poolside
Artificial Intelligence
MemberofEngineering(Pre-training/DataResearch)
Neural analysis suggests this role is
optimal for Mid+ candidates.
“Member of Engineering (Pre-training / Data Research) at Poolside. Skills: Large Language Models (LLM), Python, data quality, pretraining datasets, distributed data pipelines. improve the quality of the pretraining datasets. synthetic data generation”
Industry & Context.
improve the quality of the pretraining datasets by leveraging your previous experience, intuition and training experiments
What They're Looking For.
Must Have
machine learning and engineering background, Experience with Large Language Models (LLM), Understanding of transformer architectures and how LLMs learn, Data ablations and scaling laws, Mid-training and Post-training techniques, Training reasoning and agentic models, Experience with evals tracking model capabilities (general knowledge, reasoning, math, coding, long-context, etc), Experience in building trillion-scale pretraining datasets, familiarity with concepts like data curation, deduplication, data mixing, tokenization, curriculum, impact of data repetition, etc., Excellent programming skills in Python, prompt engineering skills, Experience working with large-scale GPU clusters and distributed data pipelines, obsession with data quality
Nice to Have
Author of scientific papers on any of the topics: applied deep learning, LLMs, source code generation, etc., Can freely discuss the latest papers and descend to fine details, Is reasonably opinionated
What You'll Do.
improve the quality of the pretraining datasets
synthetic data generation
data mix optimization
define high-quality data needs that map to missing model capabilities and downstream use cases
lead original research initiatives through short
time-bounded experiments
deploying highly technical engineering solutions into production
and diverse datasets of natural language and source code for training Poolside models and coding agents
Design and implement complex pipelines that can generate large amounts of data while maintaining high diversity and optimizing the resources available
conduct and analyze data ablations or training experiments that aim to improve the quality of the datasets generated via quantitative insights
How You'll Work.
Team & Collaboration
Closely collaborate with other teams like Pretraining, Postraining, Evals, and Product; Closely work with other teams such as Pretraining, Postraining, Evals and Product to ensure short feedback loops on the quality of the models delivered
Process & Methodology
short, time-bounded experiments
Full Job Description
ABOUT POOLSIDE In this decade, the world will create Artificial General Intelligence. There will only be a small number of companies who will achieve this. Their ability to stack advantages and pull ahead will define the winners. These companies will move faster than anyone else. They will attract the world's most capable talent. They will be on the forefront of applied research, engineering, infrastructure and deployment at scale. They will continue to scale their training to larger & more capable models. They will be given the right to raise large amounts of capital along their journey to enable this. They will create powerful economic engines. They will obsess over the success of their users and customers. Poolside exists to be this company: to build a world where AI will be the engine behind economically valuable work and scientific progress. We believe the fastest way to reach AGI lies in accelerating software development itself, by reshaping the developer experience with agentic systems, coding assistants, and the frontier models that power them. We deploy these systems directly into the development environments of security-conscious enterprises. ABOUT OUR TEAM We were founded in the US and have our home there, but our team is distributed across Europe and North America. We get our fix of in-person collaboration (and croissants) in Paris each month for 3 days, always Monday-Wednesday, with an open invitation to stay the whole week. We also do longer off-sites once a year. Our team is a multidisciplinary blend of research, engineering, and business experts. What unites us is our deep care for what we build together. We’re in a race that requires hard work, intellectual curiosity, and obsession; to balance this intensity, we’ve assembled a team of low ego and kind-hearted individuals who have built the special culture Poolside has. By building collaboratively and with intention, we create a compounding effect that moves the entire company forward towards our mis
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