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  • Research Scientist

    Kadence

    Principal research scientist job in Santa Rosa, CA

    About the Company We are a seed-stage AI company building the industry standard for evaluating and benchmarking large language models on real enterprise tasks. About the Role As a Research Scientist, you will develop new benchmarks, methodologies, and evaluation pipelines that shape how cutting-edge models are assessed, compared, and deployed in production environments. Your work will directly influence model selection and safety decisions across foundation model labs, high-growth AI product companies, and Fortune-scale enterprises. Responsibilities Benchmarking & Model Analysis Evaluate newly released models as they launch (e.g., Gemini, DeepSeek, etc.) Run large-scale assessment workflows using internal evaluation infrastructure Compare model performance across enterprise-grade task categories Design New Benchmarks from Scratch Identify high-value model application domains through research exploration Construct datasets, including labeling strategy and workforce coordination Write short โ€œwhite-paper-styleโ€ summaries explaining benchmark purpose, method, and findings Advance Automated Evaluation Methodologies Improve systems for scoring generated text beyond standard metrics Explore research in reference-free, rubric-based, and human-aligned evaluation Develop new techniques for reliability, consistency, and repeatability Cross-functional Collaboration Work closely with engineering to scale evaluation infra Partner with customers to refine evaluation relevance and task fit Influence product direction through research insights Qualifications 0-3 years post-grad experience (Master's, PhD, or equivalent applied research) Publications, preprints, or demos showing cutting-edge work Experience with diffusion models, NLP, multimodal, or benchmarking work Ability to operate independently with ambiguity Clean, maintainable research codebases Candidates from: top engineering/research universities applied AI startups well-regarded research internships Required Skills Built or contributed to a benchmark or evaluation methodology Experience in enterprise task model evaluation Stanford / top lab adjacency (per their historical hiring success) Preferred Skills Wants to publish as primary motivation Purely academic with slow timelines Big-tech culture fit concerns (Meta / Google / Salesforce specifically noted-but case-by-case) Pay range and compensation package Base Salary: up to $250K depending on background Equity: typically 0.3% - 0.5%, flexibility for exceptional candidates Rapid equity refresh possible based on impact Equal Opportunity Statement Visa sponsorship available. Relocation support. Health & dental coverage. Lunch + dinner provided, snacks & coffee. Unlimited PTO. Weekly happy hours with community guests. Team events (bowling, hiking, rock climbing, etc.). Swag program (hats, etc.). Work Environment & Culture In-person, San Francisco HQ (required). Core hours: 9-5, some teammates extend voluntarily. Most team members work 1 weekend day per week (flexible). High-ownership, low-ego, collaborative. Live demos Mondays, team lunch Thursdays, community Fridays. Early-stage pace, applied focus-not academic publishing. Tech Environment (while research-focused, exposure beneficial) Backend: Python / Django. Frontend: React + TypeScript. Infra: AWS. Evaluation frameworks + internal tooling. Why This Role Is Unique The company already collaborates with foundation model labs, high-growth AI vertical product companies, and Fortune 500 enterprises (not publicly facing). ChatGPT Vals AI $5M seed raised, runway of 2+ years at current burn. Only one research scientist is being hired-true founding impact. Opportunity to define industry standards for model trust, reliability, and certification. Positioned to become the rating agency for generative AI.
    $250k yearly 1d ago
  • research scientist - RL

    Cerebro 3.3company rating

    Principal research scientist job in Santa Rosa, CA

    Join a Leading Applied Research Lab Pushing the Boundaries of Reinforcement Learning Are you passionate about advancing the frontiers of reinforcement learning (RL)? An innovative AI research lab is seeking talented and ambitious scientists to shape the next generation of RL techniques-especially where they intersect with large models and environment generation. About the Role As an AI Research Scientist focused on RL, you will: Develop novel optimization-based methods for automated RL environment generation Establish baselines for evaluating the quality and diversity of RL environments Design infrastructure to create dynamic environments from historical datasets and agent evaluations Drive your own research agenda, contributing directly to the progress of our platform and the broader AI community What We're Looking For PhD (or equivalent experience) in machine learning, computer science or a related field Strong publication record and/or evidence of research impact (open source, deployed systems, etc.) Deep expertise in reinforcement learning and machine learning fundamentals Proficient in Python and at least one modern ML framework (such as PyTorch or JAX) Bonus Points Experience with post-training large language models (LLMs) Demonstrated software engineering skills Ability to communicate research findings effectively to both technical and non-technical audiences
    $149k-249k yearly est. 5d ago
  • Founding Applied Research Scientist (RL)

    Greylock Partners 4.5company rating

    Principal research scientist job in San Francisco, CA

    Early-stage (vertical RL) company looking to hire a Sr. Applied RS with a strong background in reinforcement learning. Qualifications: Applied Research with MS or PhD in a related field and 4 + years industry experience in deep learning and 2+ years with reinforcement learning Successful track record as a self-starter in 0->1 scenarios with a proven ability to take SOTA models into production Please note: Due to the selective nature of this service and the volume of applicants we typically receive from our job postings, a follow-up email will not be sent until a match is identified with one of the startup investments in our portfolio. About Us: Greylock is an early-stage investor in hundreds of remarkable companies including Airbnb, LinkedIn, Dropbox, Workday, Cloudera, Facebook, Instagram, Roblox, Coinbase, Palo Alto Networks, among others. More can be found about us here: ********************* We are full-time, salaried employees of Greylock who provide free candidate referrals/introductions to our active investments to help them grow/succeed (as one of the many services we provide). Please note: We are not recruiting for any roles within Greylock at this time. This job posting is for direct employment with a startup in our portfolio.
    $119k-187k yearly est. 4d ago
  • Research Scientist

    Goliath Partners

    Principal research scientist job in San Mateo, CA

    We're working with a San Francisco client that's got a research team of 50~ professionals and looking to further expand it. They are specifically looking to flesh out their Research Group by hiring a Research Scientist on a hybrid basis. They have seen $300M in a recent fund raise. Skills targeted: PhD in Physics/ Quantum Physics/ Theory/ Statistics/ Mathematics/ Computational Science or similarly related field. 2+ YoE working with AI Agents. Good exposure to LLMs. Ideally a background in Audio focused research. Alternatively Search, would also be highly advantageous. TC package of $1-1,5M with sizeable base salary & equity package. If that looks of interest, apply & Goliath will be in touch!
    $96k-161k yearly est. 1d ago
  • Research Scientist - Vision Data Infrastructure

    Storm3

    Principal research scientist job in San Francisco, CA

    โšก Research Scientists/Engineers (all levels) ๐Ÿ” Focus on Vision Data Infrastructure ๐Ÿค– Fundamental AI Research Institute ๐ŸŒŽ San Francisco Bay Area, USA ๐Ÿ’ธ $250,000 - $600,000 salary + annual bonus Come join one of the only research institutions globally with resources to compete with top AI companies =>10s of 1000s of GPUs to explore state-of-the-art research in LLMs, Multimodal and Agentic AI. Currently seeking AI talent with expertise in building scalable pipelines for vision data to support both image/video generative training and multi-modal alignment. You'll design high-performance pipelines for large-scale image and video datasets, enabling efficient pretraining, alignment, and simulation-based data generation. Responsibilities: Vision Data Sourcing & Curation Collect and organize image and video data from open datasets and the web. Handle data cleaning, filtering, deduplication, and metadata generation. Ensure ethical and compliant data collection at scale. Processing & Augmentation Build high-throughput pipelines for vision data preprocessing (frame extraction, resolution normalization, format conversion, latent caching). Implement GPU-accelerated augmentation and distributed data loading (WebDataset, TFRecords, Parquet). Synthetic & Simulation-Based Data Generation Use simulation tools (e.g., Unreal Engine 5, Isaac Sim, Unity) to generate high-quality synthetic vision data. Create specialized datasets for VLM training, visual reasoning, and agent interaction. Requirements: Strong experience with data engineering, computer vision, or machine learning infrastructure. Expertise in building and scaling ETL/data pipelines for large unstructured datasets. Proficiency with Python, PyTorch, and distributed data frameworks (e.g., Ray, Spark, Dask). Experience with WebDataset, TFRecords, Parquet, or similar high-throughput data formats. Familiarity with GPU-accelerated preprocessing, NVIDIA DALI, or equivalent systems. Understanding of image/video codecs, data compression, and cloud storage optimization. Preferred Experience: Prior work with simulation-based or synthetic data generation using Unreal Engine, Isaac Sim, or Unity. Experience curating datasets for multimodal or vision-language model training. Knowledge of data ethics, privacy, and compliance frameworks for large-scale AI datasets. Experience contributing to open datasets or data-centric AI research. Why apply: Opportunity to join a fast-growing core team that are already pushing AI breakthroughs Highly competitive salary package Work alongside ambitious and bright superstars from tech and academia Medical, Dental and Vision Insurance Relocation package available ๐ŸŒŽ San Francisco Bay Area, USA ๐Ÿ“ง Interested in applying? Please click on the โ€˜Easy Apply' button or alternatively email me your resume at ************************
    $95k-160k yearly est. 2d ago
  • AI/ML Scientist

    Saragossa

    Principal research scientist job in San Mateo, CA

    AI/ML Scientist - Build the Future of Physics AI- $250,000 to $275,000 Salary You will be part researcher, part builder, part pioneer, someone who thrives at the intersection of machine learning and physics based simulation. The platform is built on massively scalable, cloud native simulation technology that makes it possible to run thousands of high fidelity simulations quickly and easily. This foundation unlocks something big, enabling the generation of large scale datasets that power the next generation of ML models across industries. You will be on the front lines of building and productizing new machine learning approaches for physics based problems, from CFD to thermal simulation. Your work will not just live in a paper, it will deliver measurable value to customers, shape new product capabilities, and push the boundaries of what is possible in Physics AI. You know that rush when your work goes from experiment to production, when the models perform, the results hold up, and you can see the impact firsthand? That is what this role is about. Ready to shape the future of Physics AI? Let's talk. No up to date resume required.
    $250k-275k yearly 2d ago
  • Senior RL Research Scientist

    Deeprec.Ai

    Principal research scientist job in San Francisco, CA

    Senior RL Research Scientist / Reinforcement Learning Scientist Join a frontier AI team building systems that can act in the physical world, experimenting, optimizing, and controlling real processes through advanced ML, simulation, and automation. This group is pushing the boundaries of physical intelligence, backed by significant long-term funding and a mandate to invent from first principles. If you want to: Work on problems few teams in the world can touch Build RL systems that power real tools, workflows, and scientific processes Operate in a fast, high-ownership, deeply technical culture โ€ฆthis is the kind of role that defines a career. The Role You'll design and deploy reinforcement learning systems that control complex tools, optimize multi-step processes, and operate across high-fidelity simulations and digital twins. Expect hands-on research, real-world experimentation, and tight collaboration with teams across ML, simulation, and systems engineering. What You'll Do Build RL environments for tool control, workflow optimization, and long-horizon decision-making Develop safe and constrained RL methods, verifier-driven rewards, and offline to online training pipelines Create state/action representations and evaluation frameworks for reliable policy behavior Work with cross-functional researchers and engineers to deploy RL agents into real workflows What You Bring Strong background in RL, optimal control, or sequential decision-making Experience applying RL to complex simulated or physical systems Familiarity with safe/constrained RL, verifiers, or advanced evaluation pipelines Ability to design environments, rewards, and diagnostics at scale Comfort working across ML, simulation, and systems interfaces
    $118k-189k yearly est. 3d ago
  • Senior RL Research Scientist

    Acceler8 Talent

    Principal research scientist job in San Francisco, CA

    ๐Ÿ’ก What if your next role let you design reinforcement learning systems that directly control real-world science -training agents that run experiments, tune physical tools, and accelerate discovery from months to days? ๐Ÿš€ Our client - a hyper-talent-dense physical-AI startup backed by top-tier builders across frontier AI and deep tech - is hiring a Senior RL Research Scientist (San Francisco / Redwood City, In-Person). They're building Physical Superintelligence: AI that can ask any scientific question about the physical world and get a real answer in days, not years-by pairing large models with massive automated โ€œexperiment factories.โ€ The role: ๐ŸŽฏ Own RL for real-world tool control and long-horizon workflows across biology, chemistry, materials, and robotics ๐Ÿงช Build RL environments grounded in physics, simulation, and digital twins-not toy benchmarks ๐Ÿ›ก๏ธ Design safe / constrained RL + verifier-integrated rewards to keep agents reliable in high-stakes domains ๐Ÿ“ˆ Drive offline โ†’ online transitions and evaluation pipelines as agents learn from and act on real telemetry ๐Ÿค Partner across LLM, agent systems, simulation, and physical-tooling teams to deploy policies into production workflows โš™๏ธ High-ownership algorithm + systems work where you shape the foundations of physical-AI autonomy Why join? ๐ŸŒ Work at the frontier of real-world impact-from multi-cancer early detection to general scientific discovery ๐Ÿญ Operate on a uniquely scaled platform: 20k+ sq ft automated facilities producing real experimental feedback loops ๐Ÿ’ฐ Competitive salary + meaningful equity ๐Ÿš€ Tiny, world-class team with a โ€œbest-person-you've-worked-withโ€ talent bar ๐Ÿข In-person, high-velocity environment with deep collaboration across SF + Redwood City ๐Ÿ“ฉ Interested? Apply now
    $118k-189k yearly est. 1d ago
  • Scientist/Sr. Scientist-Stem Cell Biology/Embryology

    Commonwealth Sciences, Inc.

    Principal research scientist job in Santa Rosa, CA

    located in San Francisco, CA Responsibilities of the Scientist/Sr. Scientist-Stem Cell Biology/Embryology: Design and execute experiments in stem cell differentiation, organoid generation, and tissue engineering. Innovate then execute experiments to generate and differentiate human stem cells, develop functional assays, assess and interpret experimental workflows Perform mammalian embryo dissections, tissue isolations, and culture experiments to study and model developmental processes. Apply principles of developmental biology and embryology to guide tissue maturation and patterning. Collaborate with biomaterials and engineering teams to integrate cells and tissues. Develop and optimize protocols for reproducible tissue generation and maintenance. Test novel stem cell culture conditions, sort, screen, expand and differentiate hi PSCs according to latest protocols and newly developed approaches. Requirements of the Scientist/Sr. Scientist-Stem Cell Biology/Embryology: PhD in biological sciences, stem cell biology, genetics or related field. 2+ years hands-on expertise in stem cell culture (iPSCs/ESCs). Hands-on experience with mammalian embryos, including dissections and culture. Experience in molecular biology and strong problem solving skills.
    $93k-153k yearly est. 5d ago
  • Senior Research Scientist, Biophysics

    Yoh, A Day & Zimmermann Company 4.7company rating

    Principal research scientist job in South San Francisco, CA

    Yoh is looking for a skilled and driven Senior Research Scientist, Biophysics with hands-on experience in small molecule drug discovery to join our collaborative Lead Discovery team. This is a lab-based role focused on the biophysical and mechanistic characterization of small molecule-protein interactions to support our drug discovery pipeline. This candidate must have hands on experience with designing and executing binding characterization studies using SPR. Industry: Discovery and Development Location: South San Francisco, CA Key Responsibilities: Design and execute binding characterization studies using SPR (Biacore S200 and 8K+). Conduct routine compound screening and mechanistic studies using biophysical assays (e.g., nano DSF, DLS, Spectral Shift). Manage and coordinate outsourced biophysical studies with CROs. Analyze and interpret data to support SAR and lead optimization across multiple projects. Maintain detailed experimental records and present findings in internal meetings and reports. Qualifications: PhD in Biophysics, Biochemistry, or a related field. Minimum 3 years of relevant industry experience in small molecule drug discovery biophysics. Proven expertise in SPR assay development and data interpretation. Demonstrated expertise in designing, developing, and interpreting biophysical characterization of small molecule-protein interactions by SPR. Strong familiarity with additional biophysical techniques (TSA, DLS, Spectral Shift, NMR, ITC, etc.). Proficiency with data analysis and graphing tools is a plus. #IND-SPG Estimated Min Rate: $70.00 Estimated Max Rate: $80.00 What's In It for You? We welcome you to be a part of the largest and legendary global staffing companies to meet your career aspirations. Yoh's network of client companies has been employing professionals like you for over 65 years in the U.S., UK and Canada. Join Yoh's extensive talent community that will provide you with access to Yoh's vast network of opportunities and gain access to this exclusive opportunity available to you. Benefit eligibility is in accordance with applicable laws and client requirements. Benefits include: Medical, Prescription, Dental & Vision Benefits (for employees working 20+ hours per week) Health Savings Account (HSA) (for employees working 20+ hours per week) Life & Disability Insurance (for employees working 20+ hours per week) MetLife Voluntary Benefits Employee Assistance Program (EAP) 401K Retirement Savings Plan Direct Deposit & weekly epayroll Referral Bonus Programs Certification and training opportunities Note: Any pay ranges displayed are estimations. Actual pay is determined by an applicant's experience, technical expertise, and other qualifications as listed in the job description. All qualified applicants are welcome to apply. Yoh, a Day & Zimmermann company, is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or status as a protected veteran. Visit ************************************************ to contact us if you are an individual with a disability and require accommodation in the application process. For California applicants, qualified applicants with arrest or conviction records will be considered for employment in accordance with the Los Angeles County Fair Chance Ordinance for Employers and the California Fair Chance Act. All of the material job duties described in this posting are job duties for which a criminal history may have a direct, adverse, and negative relationship potentially resulting in the withdrawal of a conditional offer of employment. It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability. By applying and submitting your resume, you authorize Yoh to review and reformat your resume to meet Yoh's hiring clients' preferences. To learn more about Yoh's privacy practices, please see our Candidate Privacy Notice: **********************************
    $70 hourly 3d ago
  • Scientist II

    Ultimate Staffing 3.6company rating

    Principal research scientist job in Oakland, CA

    Pay Rate Range: $50.00/hr. - $55.24/hr. Target Pay Rate: $55.24/hr. Duration: 3 Months Onsite Shift (if applicable): M-F 8:00 AM - 5:00 PM JOB DESCRIPTION SUMMARY/JOB PURPOSE: The Scientist II will be joining the Biotherapeutics Translational Pharmacology team to support our research programs. This position is primarily responsible for developing, optimizing and reporting out data for Bioanalytical assays for Antibody Drug Conjugates (ADC) to include ELISA, LC-MS and hybrid LC-MS techniques. This job will require the candidate to have excellent organization, communication, and teamwork skills, as well as flexibility and versatility, to meet tight deadlines in a dynamic, fast-moving environment. ESSENTIAL DUTIES AND RESPONSIBILITIES: * Responsible for running analytical samples from nonclinical PK studies using ELISA, LC-MS and hybrid LC-MS techniques * Operation and troubleshooting of automated instrumentation * Collaborates with Biotherapeutics team members to support project advancement. * Maintains electronic laboratory notebook in a complete, consistent, and timely manner in accordance with company intellectual property policies and practices. * Prepares and organizes data for presentation. May present data and status reports at individual, group, and departmental research meetings under general supervision. * Adherence to excellent health and safety practices and compliance with applicable EH&S safety rules and participates in mandatory safety training programs. * Other responsibilities as assigned SUPERVISORY RESPONSIBILITIES: * No supervisory responsibilities EDUCATION/EXPERIENCE/KNOWLEDGE & SKILLS: Education: * Bachelor's degree in related discipline and a minimum of four years of related experience; or * Master's degree in related discipline and a minimum of two years of related experience; or, * Equivalent combination of education and experience. Experience: * Drug discovery experience is necessary with hands-on bioanalytical assay development with an excellent understanding of fundamental processes. * Experience with ELISA, LC-MS and Hybrid LC-MS is required * Experience using WinNonlin and PRISM applications are preferred. Knowledge/Skills: * Highly self-motivated with exceptional attention to detail is required. * Thorough knowledge of activities related to bioanalytical assay development and data generation * Excellent verbal and written communication skills with the ability to follow written instructions and SOPs. * Ability to multi-task and excellent time management skills. * Excellent work ethic, working effectively in both a team environment and independently. * Thorough proficiency in MS Word, MS PowerPoint and MS Excel is required. WORKING CONDITIONS: * Primarily working in laboratory and office environment. * Potential handling of hazardous materials, and brief periods of working in both 4ยฐC and -20ยฐC environments. * May be required to work weekends as needed. All qualified applicants will receive consideration for employment without regard to race, color, national origin, age, ancestry, religion, sex, sexual orientation, gender identity, gender expression, marital status, disability, medical condition, genetic information, pregnancy, or military or veteran status. We consider all qualified applicants, including those with criminal histories, in a manner consistent with state and local laws, including the California Fair Chance Act, City of Los Angeles' Fair Chance Initiative for Hiring Ordinance, and Los Angeles County Fair Chance Ordinance. For unincorporated Los Angeles county, to the extent our customers require a background check for certain positions, the Company faces a significant risk to its business operations and business reputation unless a review of criminal history is conducted for those specific job positions.
    $50-55.2 hourly 5d ago
  • Product Development Scientist

    Notco

    Principal research scientist job in Santa Rosa, CA

    We are a group of people united by a strong purpose. We want you to get to know us, and Giuseppe, our very own artificial intelligence. We love good food, but above all, we love the planet, and that's why, to protect it, we reinvent the food industry, one delicious bite at a time, elevating what we eat, through our technology and based on plants. Our recipe has three mega-important components: science, technology, and of course, disruptive talents who work daily to create a better future. At NotCo we are not and do not seek to be the perfect company, but rather the right one. We are here to produce changes, and that is why we dare, fail, and sometimes achieve incredible successes. We are currently looking for a Product Development Scientist for our NotCo B2B Research & Development located in San Francisco, California, requiring an active on-site presence. This position will report to our R&D Sr. Team Lead and the incumbent will work cross-functionally to ensure R&D activities are successfully deployed locally. Responsible for the: Independently conducts day-to-day product development activities as directed by the manager across multiple projects. This includes supporting activities related to the full product lifecycle process (from product concept to successful commercial launch as needed)and supporting process development, scale-up and technology transfer Supports the design and execution of bench-top tests, pilot-plant trials and full-scale formulations to deliver high-quality food products that meet and exceed the sensory, cost, and other performance targets Proactively proposes and uses sensory and analytical analysis to guide and validate the development process Maintains detailed documentation, experiment tracking and outcomes, and documents finished goods and ingredient specifications Provides feedback to project lead regarding relevant technical and process information Communicates proactively and effectively with cross-functional teams, clearly articulating perspectives and trade-offs related to new product development goals Utilizes NotCo's proprietary AI technology to develop and improve food products Supports formula validation activities as well as process development, scale-up and technology transfer Engages in client communications and workshops, bringing technical Maintains detailed documentation across all R&D activities in a timely manner Qualifications / Requirements: Bachelor's degree in Food Engineering, Food Science, Engineering in Biotechnology or a similar discipline. 2 + years of Food R&D experience is desired, preferably across both food and beverage categories. Be agile, adaptable, and thrive in a dynamic and changing culture; works relentlessly to overachieve, anticipate obstacles, and create plans to overcome them. Adapts easily to changing priorities and direction based on new project learnings and team priorities. Demonstrated competency to effectively communicate (oral & written) cross-functionally with solid collaboration skills. Comfortable in client-facing situations and able to communicate complex topics clearly and simply. Excel in a startup environment, is excited to create new procedures and processes from scratch and has a strong entrepreneurial mindset. Be a problem solver, have a general manager mindset, and take the initiative to get the job done Possess strong planning, project management, and execution skills, and the ability to articulate where and how you have used them. Rigorous data-driven/analytical capability and ability and presence to present data effectively to a leadership team Work well in teams and cross-functional groups in a matrixed environment, both regionally and globally Possesses strong computer skills, including a high level of proficiency in MS Office, specifically Excel Authorization to work in the U.S. is required Ability to travel up to 50% of the time, including international travel and extended trips. NotCo is committed to fair and equitable compensation practices. The pay range for this role is $65,000 - $75,000. Actual compensation packages are based on several factors that are unique to each candidate, including but not limited to skill set, depth of experience, certifications, and specific work location. This may be different in other locations due to differences in the cost of labor. We are an equal opportunity employer. All applicants will be considered for employment without attention to race, color, religion, sex, sexual orientation, gender identity, national origin, veteran or disability status.
    $65k-75k yearly 2d ago
  • Postdoctoral Researcher

    University of California, San Francisco 4.6company rating

    Principal research scientist job in San Francisco, CA

    The University of California, San Francisco (UCSF) is dedicated to advancing health worldwide through innovative research, high-quality education, and exceptional patient care. UCSF is recognized for fostering collaboration among its renowned graduate schools, medical center, and research programs. The university is committed to excellence, driving breakthroughs that improve lives. UCSF serves as a hub for scientific discovery and education in the heart of San Francisco, CA. The position is in the group of Drs. Boris Bastian and Iwei Yeh at UCSF's Helen Diller Family Comprehensive Cancer Center, leaders in melanoma genetics and translational research. The lab offers a stimulating, collaborative environment with access to cutting-edge technologies and interdisciplinary expertise. Role Description This is a full-time, on-site role for a Postdoctoral Researcher based in the Melanoma Discovery Lab at the University of California, San Francisco (UCSF) is seeking a highly motivated postdoctoral fellow (MD or PhD) to study systemic immune responses to gene fusion-driven cancers. This project explores how potent oncogenic fusions can initiate neoplastic growth while simultaneously triggering immune surveillance, with Spitz tumors serving as a model. The broader aim is to understand how similar transient, immune-contained lesions may arise in other tissues and be eliminated before clinical detection. The fellow will join a collaborative effort between cancer geneticists/melanoma biologists and genetic immunologists, combining genomic and immunologic approaches to study the systemic response to fusion-driven neoplasms. Qualifications MD or PhD in cancer biology, immunology, genetics, or related fields Strong research background and publication record Experience with molecular, genomic, or immunologic methods preferred Intellectual curiosity about tumor-immune system interactions Proficiency in Laboratory Skills and experience in conducting hands-on experimental work Strong Research and Data Analysis capabilities with attention to detail Experience with publication in peer-reviewed journals is a plus To Apply Send a CV, brief statement of research interests, and contact information for three references to **********************.
    $63k-81k yearly est. 2d ago
  • Senior Research Associate / Scientist

    Compass Consulting

    Principal research scientist job in South San Francisco, CA

    Our client is a research and development company whose mission is to harness advanced technologies to increase our understanding of the biology that controls lifespan. Support the team in establishing in vitro models of age-related neurodegenerative diseases aimed at target validation and mechanistic biology. Optimize existing protocols for iPSC-derived cell models. Follow quality control and reproducibility standards for the cell culture systems. Track and communicate the status of ongoing experiments with the team and iteratively optimize experiments Analyze, interpret data and rigorously document protocols, raw data and results.
    $88k-150k yearly est. 54d ago
  • Research Scientist

    Kadence

    Principal research scientist job in San Francisco, CA

    About the Company We are a seed-stage AI company building the industry standard for evaluating and benchmarking large language models on real enterprise tasks. About the Role As a Research Scientist, you will develop new benchmarks, methodologies, and evaluation pipelines that shape how cutting-edge models are assessed, compared, and deployed in production environments. Your work will directly influence model selection and safety decisions across foundation model labs, high-growth AI product companies, and Fortune-scale enterprises. Responsibilities Benchmarking & Model Analysis Evaluate newly released models as they launch (e.g., Gemini, DeepSeek, etc.) Run large-scale assessment workflows using internal evaluation infrastructure Compare model performance across enterprise-grade task categories Design New Benchmarks from Scratch Identify high-value model application domains through research exploration Construct datasets, including labeling strategy and workforce coordination Write short โ€œwhite-paper-styleโ€ summaries explaining benchmark purpose, method, and findings Advance Automated Evaluation Methodologies Improve systems for scoring generated text beyond standard metrics Explore research in reference-free, rubric-based, and human-aligned evaluation Develop new techniques for reliability, consistency, and repeatability Cross-functional Collaboration Work closely with engineering to scale evaluation infra Partner with customers to refine evaluation relevance and task fit Influence product direction through research insights Qualifications 0-3 years post-grad experience (Master's, PhD, or equivalent applied research) Publications, preprints, or demos showing cutting-edge work Experience with diffusion models, NLP, multimodal, or benchmarking work Ability to operate independently with ambiguity Clean, maintainable research codebases Candidates from: top engineering/research universities applied AI startups well-regarded research internships Required Skills Built or contributed to a benchmark or evaluation methodology Experience in enterprise task model evaluation Stanford / top lab adjacency (per their historical hiring success) Preferred Skills Wants to publish as primary motivation Purely academic with slow timelines Big-tech culture fit concerns (Meta / Google / Salesforce specifically noted-but case-by-case) Pay range and compensation package Base Salary: up to $250K depending on background Equity: typically 0.3% - 0.5%, flexibility for exceptional candidates Rapid equity refresh possible based on impact Equal Opportunity Statement Visa sponsorship available. Relocation support. Health & dental coverage. Lunch + dinner provided, snacks & coffee. Unlimited PTO. Weekly happy hours with community guests. Team events (bowling, hiking, rock climbing, etc.). Swag program (hats, etc.). Work Environment & Culture In-person, San Francisco HQ (required). Core hours: 9-5, some teammates extend voluntarily. Most team members work 1 weekend day per week (flexible). High-ownership, low-ego, collaborative. Live demos Mondays, team lunch Thursdays, community Fridays. Early-stage pace, applied focus-not academic publishing. Tech Environment (while research-focused, exposure beneficial) Backend: Python / Django. Frontend: React + TypeScript. Infra: AWS. Evaluation frameworks + internal tooling. Why This Role Is Unique The company already collaborates with foundation model labs, high-growth AI vertical product companies, and Fortune 500 enterprises (not publicly facing). ChatGPT Vals AI $5M seed raised, runway of 2+ years at current burn. Only one research scientist is being hired-true founding impact. Opportunity to define industry standards for model trust, reliability, and certification. Positioned to become the rating agency for generative AI.
    $250k yearly 1d ago
  • research scientist - RL

    Cerebro 3.3company rating

    Principal research scientist job in San Francisco, CA

    Join a Leading Applied Research Lab Pushing the Boundaries of Reinforcement Learning Are you passionate about advancing the frontiers of reinforcement learning (RL)? An innovative AI research lab is seeking talented and ambitious scientists to shape the next generation of RL techniques-especially where they intersect with large models and environment generation. About the Role As an AI Research Scientist focused on RL, you will: Develop novel optimization-based methods for automated RL environment generation Establish baselines for evaluating the quality and diversity of RL environments Design infrastructure to create dynamic environments from historical datasets and agent evaluations Drive your own research agenda, contributing directly to the progress of our platform and the broader AI community What We're Looking For PhD (or equivalent experience) in machine learning, computer science or a related field Strong publication record and/or evidence of research impact (open source, deployed systems, etc.) Deep expertise in reinforcement learning and machine learning fundamentals Proficient in Python and at least one modern ML framework (such as PyTorch or JAX) Bonus Points Experience with post-training large language models (LLMs) Demonstrated software engineering skills Ability to communicate research findings effectively to both technical and non-technical audiences
    $150k-251k yearly est. 5d ago
  • Research Scientist

    Goliath Partners

    Principal research scientist job in Santa Rosa, CA

    We're working with a San Francisco client that's got a research team of 50~ professionals and looking to further expand it. They are specifically looking to flesh out their Research Group by hiring a Research Scientist on a hybrid basis. They have seen $300M in a recent fund raise. Skills targeted: PhD in Physics/ Quantum Physics/ Theory/ Statistics/ Mathematics/ Computational Science or similarly related field. 2+ YoE working with AI Agents. Good exposure to LLMs. Ideally a background in Audio focused research. Alternatively Search, would also be highly advantageous. TC package of $1-1,5M with sizeable base salary & equity package. If that looks of interest, apply & Goliath will be in touch!
    $94k-157k yearly est. 1d ago
  • Senior LLM Research Scientist

    Deeprec.Ai

    Principal research scientist job in San Francisco, CA

    A frontier-stage research group is building a new class of AI systems designed to reason, plan, and act across the physical world. Their mission is to create intelligent agents capable of experimenting, engineering, and constructing in ways that dramatically accelerate scientific and industrial progress. This team combines deep technical pedigree with real-world wins at scale, including major government-funded initiatives. They operate where advanced model research meets robotics, simulation, and automated engineering systems, offering the kind of impact only possible when first-principles science meets ambitious execution. Joining means stepping into a high-ownership environment where you shape core capabilities end-to-end, influence the direction of physical-world intelligence, and help build technology the world has never seen before. Why This Role Is Compelling Work on cutting-edge reasoning, planning, and tool-use models that directly control autonomous engineering systems. Push the limits of SFT, RLHF, DPO, verifier-guided RL, and long-horizon planning in a setting where your research immediately translates into real-world capability. Operate in a high-velocity research culture with exceptional peers across agent systems, simulation, data, and complex toolchains. Have outsized ownership in a small team tackling one of the most ambitious technical problems of this decade. Role Overview The team is looking for an LLM Research Scientist to pioneer next-generation reasoning and agent architectures. Your work will span model design, alignment strategies, structured tool orchestration, and experimentation with agents interacting across real engineering workflows. This position blends deep research with hands-on systems integration, offering both autonomy and scope to lead foundational progress. Key Responsibilities Develop advanced models and prompting systems for planning, multi-step reasoning, and structured tool use. Lead training initiatives across SFT, RLHF/DPO, verifier-guided RL, and modular expert architectures to strengthen robustness and controllability. Define schemas, tool-calling strategies, policy constraints, safety mechanisms, and recovery pathways for agent behavior. Partner closely with engineering, simulation, and data teams to test, train, and evaluate models embedded in real production-like toolchains. Qualifications Significant experience in LLM research, agent reasoning models, or structured tool-use frameworks. Strong background working with SFT, RLHF, DPO, or reinforcement-learning-from-verification methods. Demonstrated ability to design, analyze, and improve long-horizon behaviors and decomposition strategies. Comfortable working across ML research, systems engineering, and real-world experimentation in a fast-moving environment. A track record of excellence and ownership in technically demanding domains.
    $118k-189k yearly est. 3d ago
  • Senior LLM Research scientist

    Acceler8 Talent

    Principal research scientist job in San Francisco, CA

    ๐Ÿ’ก What if your next role let you push the frontier of LLM planning and tool-use-building agents that don't just talk about the physical world, but act in it to engineer, experiment, and manufacture autonomously? ๐Ÿš€ Our client - a hyper-talent-dense physical-AI startup backed by top-tier builders across frontier AI and deep tech - is hiring a Senior LLM Research Scientist (San Francisco / Redwood City, In-Person). They're building Physical Superintelligence: AI systems with general physical ability-the capacity to experiment, engineer, or manufacture anything. Instead of only learning from static data, their models generate new data through automated real-world experimentation at massive scale. The role: ๐Ÿง  Develop planning, reasoning, and structured tool-use models that power autonomous engineering agents ๐Ÿงช Lead SFT + preference optimization work (RLHF / DPO) to push capability and reliability ๐Ÿ›ก๏ธ Build verifier-guided RL + safety constraints for robust long-horizon agent behavior ๐Ÿ”ง Design tool-calling schemas, recovery logic, and policy constraints so agents can operate real toolchains ๐Ÿค Partner across agent systems, data infra, simulation, and tooling teams to train and evaluate in production workflows โš™๏ธ High-ownership research + systems integration on core models and agent behavior Why join? ๐ŸŒ Real-world impact at national scale-accelerating physical discovery, not just model training ๐Ÿญ A uniquely scaled platform for learning with automated experimental facilities generating new feedback loops ๐Ÿ’ฐ Competitive salary + meaningful equity ๐Ÿš€ Tiny, elite team with extremely high technical bar and low ego ๐Ÿข In-person, high-velocity environment split across SF + Redwood City ๐Ÿ“ฉ Interested? Apply now!
    $118k-189k yearly est. 1d ago
  • Product Development Scientist

    Notco

    Principal research scientist job in San Francisco, CA

    We are a group of people united by a strong purpose. We want you to get to know us, and Giuseppe, our very own artificial intelligence. We love good food, but above all, we love the planet, and that's why, to protect it, we reinvent the food industry, one delicious bite at a time, elevating what we eat, through our technology and based on plants. Our recipe has three mega-important components: science, technology, and of course, disruptive talents who work daily to create a better future. At NotCo we are not and do not seek to be the perfect company, but rather the right one. We are here to produce changes, and that is why we dare, fail, and sometimes achieve incredible successes. We are currently looking for a Product Development Scientist for our NotCo B2B Research & Development located in San Francisco, California, requiring an active on-site presence. This position will report to our R&D Sr. Team Lead and the incumbent will work cross-functionally to ensure R&D activities are successfully deployed locally. Responsible for the: Independently conducts day-to-day product development activities as directed by the manager across multiple projects. This includes supporting activities related to the full product lifecycle process (from product concept to successful commercial launch as needed)and supporting process development, scale-up and technology transfer Supports the design and execution of bench-top tests, pilot-plant trials and full-scale formulations to deliver high-quality food products that meet and exceed the sensory, cost, and other performance targets Proactively proposes and uses sensory and analytical analysis to guide and validate the development process Maintains detailed documentation, experiment tracking and outcomes, and documents finished goods and ingredient specifications Provides feedback to project lead regarding relevant technical and process information Communicates proactively and effectively with cross-functional teams, clearly articulating perspectives and trade-offs related to new product development goals Utilizes NotCo's proprietary AI technology to develop and improve food products Supports formula validation activities as well as process development, scale-up and technology transfer Engages in client communications and workshops, bringing technical Maintains detailed documentation across all R&D activities in a timely manner Qualifications / Requirements: Bachelor's degree in Food Engineering, Food Science, Engineering in Biotechnology or a similar discipline. 2 + years of Food R&D experience is desired, preferably across both food and beverage categories. Be agile, adaptable, and thrive in a dynamic and changing culture; works relentlessly to overachieve, anticipate obstacles, and create plans to overcome them. Adapts easily to changing priorities and direction based on new project learnings and team priorities. Demonstrated competency to effectively communicate (oral & written) cross-functionally with solid collaboration skills. Comfortable in client-facing situations and able to communicate complex topics clearly and simply. Excel in a startup environment, is excited to create new procedures and processes from scratch and has a strong entrepreneurial mindset. Be a problem solver, have a general manager mindset, and take the initiative to get the job done Possess strong planning, project management, and execution skills, and the ability to articulate where and how you have used them. Rigorous data-driven/analytical capability and ability and presence to present data effectively to a leadership team Work well in teams and cross-functional groups in a matrixed environment, both regionally and globally Possesses strong computer skills, including a high level of proficiency in MS Office, specifically Excel Authorization to work in the U.S. is required Ability to travel up to 50% of the time, including international travel and extended trips. NotCo is committed to fair and equitable compensation practices. The pay range for this role is $65,000 - $75,000. Actual compensation packages are based on several factors that are unique to each candidate, including but not limited to skill set, depth of experience, certifications, and specific work location. This may be different in other locations due to differences in the cost of labor. We are an equal opportunity employer. All applicants will be considered for employment without attention to race, color, religion, sex, sexual orientation, gender identity, national origin, veteran or disability status.
    $65k-75k yearly 2d ago

Learn more about principal research scientist jobs

How much does a principal research scientist earn in Fairfield, CA?

The average principal research scientist in Fairfield, CA earns between $110,000 and $249,000 annually. This compares to the national average principal research scientist range of $87,000 to $184,000.

Average principal research scientist salary in Fairfield, CA

$165,000
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