---
title: 'Software Engineer, AI Platform at Chai Discovery'
canonical: 'https://feeny.ai/job/software-engineer-ai-platform-chai-discovery-san-francisco-nhrc4kpbqx4m'
type: 'job'
last_seen: '2026-10-19'
---

# Software Engineer, AI Platform at Chai Discovery

- **Company:** Chai Discovery
- **Location:** San Francisco, CA
- **Employment:** full-time
- **Posted:** 2026-10-12
- **Last confirmed live:** 2026-10-19
- **Apply:** https://jobs.ashbyhq.com/chaidiscovery/ad8dd3de-8139-4385-8c5a-566a359e9be0

## Job description

## About Chai Discovery

Chai Discovery builds the computer-aided design suite for molecules. [Eli Lilly](https://endpoints.news/eli-lilly-chai-discovery-sign-ai-software-deal/), [GSK](https://endpoints.news/chai-discovery-signs-gsk-deal-to-make-biologics-with-ai/), [Pfizer](https://www.forbes.com/sites/amyfeldman/2026/06/04/why-pfizer-and-eli-lilly-are-betting-on-this-13-billion-ai-drug-discovery-startup/), [Bristol Meyers](https://www.linkedin.com/feed/update/urn:li:activity:7496300911523246080/), [argenx](https://x.com/chaidiscovery/status/2077422480617267230?s=20) and [Novartis](https://www.chaidiscovery.com/news/novartis-partnership) all use Chai to power drug discovery programs. AI is reinventing life sciences the same way it reinvented software engineering, and our team is building that future. We train frontier models that learn the underlying foundations of biochemical structure and interaction. We pair this with a computational workspace to iterate on molecules from idea to medicine, helping scientists move faster and develop medicines beyond the reach of existing methods. We value diverse perspectives and are ready to find greatness in unexpected places.

## About the role

Build the AI platform that lets scientists direct research programs with agents. We believe that as Chai's models get more powerful, scientists will focus more on fundamental problems and biological hypotheses, and delegate more of the subtasks to answer them to agents. Making this possible requires inventing the abstractions through which people, agents, and Chai’s models collaborate.

- Work with scientists and model researchers to define how agents use Chai’s foundation models to design molecules and guide experiments.
- Build products that shorten the cycle from idea ➝ to experiment ➝ to the next decision, while scientists monitor and direct the work.
- Build the core abstractions for agent execution, model inference, and scientific tools so new capabilities come together fluidly across the workspace.

## About you

We look for technical depth, strong software architecture, and product judgment, with experience building complex applications or agent systems. You can find clear abstractions in a messy domain and build systems that hold up as their scope grows. We value a practical understanding of where agents fail and how to tell whether they’re doing useful work.

## We offer

The opportunity to work at the vanguard of AI research and frontier biology, with world-class people, on a mission that matters. We protect & promote a culture of high velocity and ownership. We compensate our team accordingly.

## About Chai Discovery

## Company Overview
- **One-liner**: Chai Discovery builds frontier AI models to predict and reprogram the interactions between biochemical molecules, focusing on de novo antibody design for drug discovery.
- **Entity Type**: Private (Series B)
- **Headquarters**: San Francisco, California, United States
- **Founded**: 2024
- **Founders**: Joshua Meier, Jack Dent, Matthew McPartlon, Jacques Boitreaud

## Core Business
- **Primary industry**: AI-powered drug discovery and biotechnology
- **Target customers**: B2B — Large pharmaceutical and biotech companies (e.g., Eli Lilly)
- **Mission or purpose statement**: "Transforming biology from a scientific practice into an engineering discipline" [chaidiscovery.com](https://www.chaidiscovery.com/)

## Products & Services
- **Chai-2**: A frontier AI model designed for de novo antibody design. It can design antibodies against challenging targets with atomic precision, moving past simple binding toward real therapeutic viability. The company describes it as a "computer-aided design suite" for molecules. [techcrunch.com](https://techcrunch.com/2026/01/16/from-openais-offices-to-a-deal-with-eli-lilly-how-chai-discovery-became-one-of-the-flashiest-names-in-ai-drug-development/), [chaidiscovery.com](https://www.chaidiscovery.com/)

## Market Standing
- **Valuation/Market Cap**: $1.3 billion (as of December 2025 Series B) [linkedin.com](https://www.linkedin.com/company/chaidiscovery)
- **Key Metric**: Total funding of $231.0M across 6 rounds. Key rounds include: Seed ($30M, led by OpenAI and Thrive Capital, 2024), Series A ($70M, 2025), and Series B ($130M, led by General Catalyst and Oak HC/FT, Dec 2025). [linkedin.com](https://www.linkedin.com/company/chaidiscovery)
- **Notable Investors/Partners**: OpenAI, Thrive Capital, General Catalyst, Oak HC/FT, Amazon Web Services (non-equity assistance). Strategic partnership with **Eli Lilly** (announced Jan 2026) for drug development. [techcrunch.com](https://techcrunch.com/2026/01/16/from-openais-offices-to-a-deal-with-eli-lilly-how-chai-discovery-became-one-of-the-flashiest-names-in-ai-drug-development/)
- **Growth Signals**: Named to Endpoints News "11 most promising biotech companies of 2025" [linkedin.com](https://www.linkedin.com/company/chaidiscovery). Headcount grew **169.2% YoY** (approx. 27 employees) [linkedin.com](https://www.linkedin.com/company/chaidiscovery). LinkedIn followers grew **508.7% yearly** [linkedin.com](https://www.linkedin.com/company/chaidiscovery). The Eli Lilly deal is a major validation of the technology by a top-tier pharma company.

## Competitive Advantages
- **Custom, homegrown AI architecture**: Every line of code is proprietary; they do not fine-tune off-the-shelf LLMs, giving them a unique technical moat. [techcrunch.com](https://techcrunch.com/2026/01/16/from-openais-offices-to-a-deal-with-eli-lilly-how-chai-discovery-became-one-of-the-flashiest-names-in-ai-drug-development/)
- **Deep ties to OpenAI**: Founders built the company out of OpenAI's offices, with Sam Altman as an early supporter and OpenAI as a seed investor, providing significant credibility and talent access. [techcrunch.com](https://techcrunch.com/2026/01/16/from-openais-offices-to-a-deal-with-eli-lilly-how-chai-discovery-became-one-of-the-flashiest-names-in-ai-drug-development/)
- **Founder expertise**: Co-founder Joshua Meier previously developed ESM1, the first transformer protein-language model, at Facebook (Meta) and worked at Generate:Biomedicines, giving the team deep domain expertise. [techcrunch.com](https://techcrunch.com/2026/01/16/from-openais-offices-to-a-deal-with-eli-lilly-how-chai-discovery-became-one-of-the-flashiest-names-in-ai-drug-development/)
- **Early market traction**: Has already secured a partnership with Eli Lilly, a top-10 global pharma company, indicating strong commercial viability ahead of many competitors. [techcrunch.com](https://techcrunch.com/2026/01/16/from-openais-offices-to-a-deal-with-eli-lilly-how-chai-discovery-became-one-of-the-flashiest-names-in-ai-drug-development/)

## Strategic Focus
- **Deploy AI in real-world drug discovery**: The company's immediate priority is to embed its models into the workflows of pharma partners like Eli Lilly to accelerate the development of novel therapeutics.
- **Unlock new classes of medicines**: By enabling atomic-precision design of antibodies, Chai aims to target historically "undruggable" biological pathways.
- **Scale the platform**: Continue to improve the Chai-2 model and expand its capabilities, with a goal of seeing first-in-class medicines enter clinical trials by the end of 2027. [techcrunch.com](https://techcrunch.com/2026/01/16/from-openais-offices-to-a-deal-with-eli-lilly-how-chai-discovery-became-one-of-the-flashiest-names-in-ai-drug-development/)

## Why Work Here
- **Culture**: Highly interdisciplinary, blending computer science, engineering, biology, chemistry, and physics. The company values deep technical talent and a "heads down" approach to pushing the frontier of AI. [chaidiscovery.com](https://www.chaidiscovery.com/careers)
- **Work policy**: In-person in **San Francisco, California** (HQ at 235 Pine St, Suite 1300). [linkedin.com](https://www.linkedin.com/company/chaidiscovery)
- **Notable perks/engineering culture**: Working at a well-funded, high-valuation startup with direct ties to OpenAI and a clear path to impact in a cutting-edge field. The team is small (~27 people) but growing fast, offering significant ownership and responsibility. Talent sources include Stripe, CERN, and Generate:Biomedicines, indicating a high-caliber peer group. [linkedin.com](https://www.linkedin.com/company/chaidiscovery)

## Sources
1. [Chai Discovery Website](https://www.chaidiscovery.com/)
2. [Chai Discovery Careers Page](https://jobs.ashbyhq.com/chaidiscovery)
3. [TechCrunch - How Chai Discovery became one of the flashiest names in AI drug development](https://techcrunch.com/2026/01/16/from-openais-offices-to-a-deal-with-eli-lilly-how-chai-discovery-became-one-of-the-flashiest-names-in-ai-drug-development/)
4. [LinkedIn - Chai Discovery Company Page](https://www.linkedin.com/company/chaidiscovery)

## Other roles at Chai Discovery

- [Software Engineer, Developer & Research Platform](https://feeny.ai/job/software-engineer-developer-research-platform-chai-discovery-san-francisco-31rqh831ftf8) — San Francisco, CA
- [Strategy](https://feeny.ai/job/strategy-chai-discovery-san-francisco-zstsq84tkjpr) — San Francisco, CA
- [Brand and Marketing](https://feeny.ai/job/brand-and-marketing-chai-discovery-san-francisco-pe90kx8dvbqk) — San Francisco, CA
- [Research Engineer, Auto Research](https://feeny.ai/job/research-engineer-auto-research-chai-discovery-san-francisco-f3asykxmvc7c) — San Francisco, CA
- [Research Engineer, ML Infrastructure](https://feeny.ai/job/research-engineer-ml-infrastructure-chai-discovery-san-francisco-gnh5gs4dwph0) — San Francisco, CA
- [First Finance Hire](https://feeny.ai/job/first-finance-hire-chai-discovery-san-francisco-h4sy4s08eqwy) — San Francisco, CA
- [Scientist, Protein Design](https://feeny.ai/job/scientist-protein-design-chai-discovery-san-francisco-11g6bx8mhvx5) — San Francisco, CA
- [Internship](https://feeny.ai/job/internship-chai-discovery-san-francisco-web8x5z637y7) — San Francisco, CA
- [Data Ops](https://feeny.ai/job/data-ops-chai-discovery-san-francisco-tt1g0j189zc0) — San Francisco, CA
- [Research Scientist](https://feeny.ai/job/research-scientist-chai-discovery-san-francisco-x8yhz96d2xxn) — San Francisco, CA