ML Researcher - Image / Video Diffusion

About Krea At Krea, we are building next-generation AI creative tools. We're dedicated to making AI intuitive and controllable for creatives - our mission is to build tools that empower human creativity, not replace it. We believe AI is a new medium that allows us to express ourselves through various formats - text, images, video, sound, and even 3D. We're building better, smarter, and more controllable tools to harness this medium. We recently took this a step forward with the launch of Krea 2, our first foundation model, built completely from scratch for aesthetic diversity and stylistic control. We've raised over $83M and are backed by world-class investors such as a16z, Bain Capital, and Abstract. We work full-time and in-person at our waterfront office in San Francisco. We care about creativity: our team includes musicians, designers, visual artists, and engineers.

We're looking for an experienced Researcher with engineering skills who can work on large-scale image and video models training experiments, with experience training image models at scale.

Our culture

• We work full-time and in-person at our North Beach office in San Francisco.

• We believe that demonstrated interest in the creative space is key: our team includes musicians, designers, visual artists and more.

• Fast iteration and execution speed. Bias towards action, agency, and independence.

What you'll do

• Train diffusion models for image and video generation on large GPU clusters.

• Fully optimize and profile large distributed training runs across model architectures, kernels, data loading, memory constraints, and communication.

• Implement and improve various distributed training strategies including FSDP, CP, SP, TP, and EP.

• Continuously improve model quality and reliability through data, model architecture, training pipeline, structuring experiments, and eval design.

• Debug distributed training errors and implement fault tolerance solutions, identifying bad GPU, NVLink, Infiniband (IB) components as well as monitoring numerical errors and NCCL issues.

• Ablate different architecture, attention, optimizer, data, and algorithmic choices to reliably improve efficiency and performance of our models.

What we're looking for

• Proven track record in working with image or video models at scale (publications or open-source contributions a plus).

• Strong proficiency in PyTorch and understanding of its inner workings.

• Strong background in distributed training paradigms such as FSDP, CP, SP, USP, TP, and EP. Knowing how different parallelism strategies work together and their tradeoffs.

• Experience in profiling and debugging large distributed training. Being comfortable with analyzing traces to identify bottlenecks and look for improvements.

• Good knowledge of low precision training / inference in FP8, NVFP4, and MXFP8.

• Solid understanding of diffusion model training pipeline across pretraining, midtraining, preference optimization, and reinforcement learning.

• Keeping up with the developments in related fields such as LLM, VLM, representation learning, and robotics research.

• Being comfortable working in a goal-oriented research environment.

• Having good judgement around when one should explore different training strategies and when it's time to commit to a specific strategy to scale compute and data.

• Comfortable working with underspecified goals. We expect every technical member to take an ambiguous research goal and break it down into concrete requirements, plans, experiment plan, and execution items.

• Good research taste — bias towards simplicity and methods that scale well with compute, data, and minimal human supervision.

• Ability to iterate rapidly, and propose creative research directions.

• Be comfortable getting your hands dirty with data and designing custom data pipelines to improve data quality.

What we offer

• Team: Work alongside a world-class team building the future of AI creative tooling

• Impact: Significant scope and company-wide impact

• Competitive compensation: generous salary & equity packages

• Health & wellness: 100% health & 99% dental/vision insurance premiums covered for employees, health FSA accounts, & long-term disability coverage

• Time off: Flexible PTO policy

• Financial planning: 401k with a 4% company-sponsored match

• Meals in the office: breakfast, lunch, dinner - you name it, we'll cover it

• Transit: Ubers covered to & from the office

• Sponsorship: We're open to sponsoring international visas where we can (e.g., STEM OPT, OPT, H-1B, O-1, E-3).

• And more!

Please note the above benefits & perks are for full-time employees