Research Scientist, Post-Training — Video Generation

Sarah Smith Fund; Palo Alto (CA); Hybrid; USD 180,000 - 260,000; Full time

Benefits offered by this job

Health benefits

401k matching

Equity

Job summary

Pika is seeking Research Scientists with expertise in RL post-training and generative modeling for large-scale video generation. You will own RL-based post-training for video diffusion/flow-matching models and help build robust reward models, collaborating with engineering and product teams.

The role covers evaluating models with human and automated metrics, distilling RL-tuned models for efficient deployment, and advancing state-of-the-art video generation capabilities in a fast-moving startup

Qualifications

• 2+ years hands-on research in post-training or generative modeling.
• Experience with RL or preference optimization on generative models.
• Strong grounding in diffusion/flow-matching models and PyTorch.

Responsibilities

• Run RL post-training (preference optimization, online RL against learned rewards) for video diffusion/flow-matching models at multi-node scale.
• Build video reward models: define target evaluation dimensions, design/configure preference data collection workflows, train and validate learned judges, and safeguard against reward hacking.
• Own post-training evaluation, including human preference studies and their correlation with automated metrics.
• Distill RL-tuned models to efficient few-step samplers while preserving alignment gains (secondary focus).

Skills

Post-training research

Generative modeling

RL

PyTorch

Distributed training

Tools

Diffusion models

Flow-matching

Video generation

Job description

About the Role

At Pika, we are pioneering the next generation of creative infrastructure built around real-time, multimodal generation and intelligent agentic platforms. We are seeking Research Scientists with expertise in RL post-training and generative modeling for large-scale video generation. The focus is on refining Pika's video generation models using RL alignment and building robust video reward models. This is a staff and lead-level opportunity.

As a key member of our research team, you will own RL-based post-training for video diffusion/flow-matching models, develop state-of-the-art reward models, and lead post-training evaluation across human and automated metrics. You will collaborate closely with engineering and product teams, shaping the frontier of real-time creative and agentic video platforms.

Scope

• RL alignment of Pika's video generation models and the reward models that drive them.
• Distillation of RL-tuned models is a secondary focus.

Responsibilities

• Run RL post-training (preference optimization, online RL against learned rewards) for video diffusion/flow-matching models at multi-node scale.
• Build video reward models: define target evaluation dimensions, design/configure preference data collection workflows, train and validate learned judges, and safeguard against reward hacking.
• Own post-training evaluation, including human preference studies and their correlation with automated metrics.
• Distill RL-tuned models to efficient few-step samplers while preserving alignment gains (secondary focus).

What We’re Looking For

Required

• 2+ years hands-on research experience in post-training or generative modeling.
• RL or preference-optimization experience on generative models with evidence of model improvement.
• Strong grounding in diffusion or flow-matching models, PyTorch, and multi-node distributed training.

Preferred

• Experience developing reward models for visual generation, including VLM-as-judge or large-scale preference data collection.
• Distillation expertise (distribution matching, consistency, adversarial approaches), ideally for video models.
• Familiarity with video-specific failure modes: temporal drift, motion and physics realism.

What We Offer

• Competitive salary and substantial equity in a high-growth startup
• Full health benefits + 401k matching and more
• Collaborative, mission-driven team environment with significant growth opportunities
• Flexible on-site/remote hybrid (HQ in Palo Alto, CA)

About Pika

Pika empowers creators by building state-of-the-art agentic and multimedia platforms. Our vision is to break down technical barriers to creativity, making real-time generative and intelligent orchestration accessible to all. Join us to shape the next evolution of creative technology!

If you are passionate about advancing RL alignment and generative modeling for video, and want to scale real-time multimodal foundation models, we want to hear from you.