Who We Are

Calico (Calico Life Sciences LLC) is an Alphabet-founded research and development company whose mission is to harness advanced technologies and model systems to increase our understanding of the biology that controls human aging. Calico will use that knowledge to devise interventions that enable people to lead longer and healthier lives. Calico’s highly innovative technology labs, its commitment to curiosity-driven discovery science and, with academic and industry partners, its vibrant drug-development pipeline, together create an inspiring and exciting place to catalyze and enable medical breakthroughs.

The Calico Postdoctoral Fellowship Program

We are seeking ambitious early career scientists to join us in our mission to increase our understanding of the biology that controls human aging. This is a unique opportunity for individuals to distinguish themselves in aging research, deepen scientific training, and develop research independence.

The Postdoctoral Fellowship is a fixed-term educational assignment (three years with a potential fourth year extension) with rolling start dates. Postdoctoral Fellows are fully integrated into Calico's labs and community.

The program is designed to train individuals to become independent investigators in an academic or industry setting upon successful completion of the assignment. Fellows will receive regular feedback and guidance from their mentor(s) and participate in a formal annual review process to review project progress and individual performance and provide career coaching. 

Responsibilities

• Lead Independent Research: Focus on their own project(s), which should pursue new research directions with dedicated resources for innovative and potentially high-risk/high-reward research
• Contribute to Calico’s Core Mission: Contribute to furthering an understanding of aging and age-related diseases
• Drive Scientific Progress: Execute experiments meticulously, analyze data (including computational analysis if applicable) and troubleshoot procedures as needed
• Publish Work: Generate work that is expected to be submitted for publication in a timely fashion upon completion of the assignment
• Collaborate and Communicate: Actively collaborate across Calico's diverse teams and scientific community, including presenting progress and results to diverse audiences of computational scientists, lab scientists, and engineers
• Professional Development: Engage with a community of other Postdoctoral Fellows and senior leadership through professional and career development opportunities, such as the annual Postdoc Summit, research-in-progress presentations, senior leader lunch sessions, and skill-building workshops

Position Requirements

The successful candidate will demonstrate characteristics valued across Calico's programs, including being a self-motivated team player, detail-oriented, extremely organized, and comfortable working on complex problems.

• Education: Must have recently completed a PhD degree in a relevant scientific or computational field
• Current PhD student applicants should be within 12 months of completing their PhD
• Applicants who have already graduated must have completed their PhD within the past 3 years and not have been employed as a postdoc at more than one other lab/company since graduation
• Experience: Must have made important contributions to science in their area, ideally demonstrated by having had a meaningful first author paper accepted for publication
• Technical Versatility (General): While specific technical skills are project-dependent, proficiency in core scientific methodologies, analytical skills, and quantitative problem-solving is essential
• Communication: Strong teamwork and communication skills are required
• Adaptability: Must be flexible and able to respond quickly to shifting priorities, demonstrating a "can-do" attitude
• Onsite Availability: Must be willing to work onsite five days per week

Application Requirements

The Postdoctoral Fellowship has four application components:

• Research proposal (1-2 page research proposal on what you’d like to investigate in the Hahn Lab during your fellowship - note that project goals may evolve during the training period)
• Updated CV with a full list of publications
• Cover letter
• List of 2-3 references that we may contact, including your PhD thesis advisor and any postdoctoral advisors (if applicable)

The estimated base salary for this role is $95,000. More information on our postdoctoral fellowship program can be found here.

About the Hahn Lab

We investigate why specific cells in the brain, such as the resident immune cells, microglia, are among the earliest and most vulnerable sites of aging, and how this vulnerability contributes to neurodegeneration. Our central mission is to decode and ultimately reprogram the brain’s immune system to dampen or reverse age‑related neuroinflammation. 

The group has established a rich arsenal of novel in vitro and in vivo discovery platforms. These include scalable heterochronic myeloid cell replacement paradigms that swap native microglia with CRISPR‑ready donor cells across young and old brains, and a new protocol for generating neuroimmune cells in vitro at a very large scale. These novel approaches are complemented by world-class CNS research equipment including custom FACS instruments, bespoke electrophysiology setups and 2 Photon in vivo imaging suites. We welcome proposals that aim to decode altered cell-cell signaling in the CNS through scalable in vitro or ex vivo experimentation. The ideal candidate is a highly motivated innovator with a strong collaborative streak and a drive to take discoveries from cellular models to whole organisms. 

Publications from the group include:

• Full Google Scholar
• Gizowski & Popova et al., Heterochronic myeloid cell replacement reveals the local brain environment as key driver of microglia aging (2025) BioRxiv
• Hahn et al., Atlas of the aging mouse brain reveals white matter as vulnerable foci (2023) Cell
• Schaum & Lehallier & Hahn et al., Ageing hallmarks exhibit organ-specific temporal signatures (2020) Nature