Day Biotech Software Engineer Jobs in California

At Lilly, the work is demanding because patients are waiting. We unite caring with discovery to help make life better for people around the world, knowing that every decision, every detail, and every day matters. Headquartered in Indianapolis, Indiana, our over 50,000 employees around the globe take on complex challenges to discover and deliver life-changing medicines, strengthen how health is understood and managed, and support the communities we serve. This is hard, urgent, selfless work-but it's work worth doing. If you're driven by purpose and ready to bring your best to work that truly matters for patients, we invite you to join us.
Organization Overview
Lilly Catalyze360 is a comprehensive approach to enabling the early-stage biotech ecosystem by democratizing access to infrastructure, expertise, and resources. Through its interconnected pillars-Lilly Ventures, Lilly Gateway Labs, Lilly ExploR&D, and Lilly TuneLab-Catalyze360 strategically removes barriers that traditionally block bold science from becoming life-changing medicines, providing biotechs with flexible combinations of capital, physical lab space, R&D capabilities, AI/ML tools, and decades of enterprise learning.
Lilly TuneLab is an artificial intelligence and machine learning (AI/ML) platform that provides biotech companies access to drug discovery models trained on years of Lilly's research data. Lilly estimates that this first release of AI models includes proprietary data obtained at a cost of over $1 billion, representing one of the industry's most valuable datasets used to train an AI system available to biotechnology companies. By integrating advanced in silico modelling and federated learning, we connect pioneering machine learning algorithms, substantial computational power, exclusive datasets, and Lilly's domain-specific knowledge to drive innovation in drug discovery and facilitate access to optimal therapies for patients.
Job Summary
TuneLab has powerful underlying AI models and point solutions. The job now is to turn them into something a biotech startup can actually use: a coherent workflow, a clean product experience, and a SaaS offering that scales.
You won't start from zero. There are working point solutions, trained models, and internal infrastructure to build on. Federated learning is a meaningful part of the work - letting biotech customers use & train Lilly's models without their data leaving their environment. Plenty else is yours to create from scratch.
We're looking for a Senior Software Engineer to be one of the early engineers on this team. You'll own meaningful product surfaces end-to-end, ship features that customers depend on, and raise the bar on what we build.
You'll partner closely with a Staff Software Engineer and the Engineering Manager. You'll have real influence on architecture and the engineering bar.
You'll work shoulder-to-shoulder with product, design, and data science, and report to the TuneLab Engineering Manager.
Key Responsibilities
Build the product

• Own product surfaces end-to-end-frontend, backend, data, integrations-whatever the problem requires. You don't hand off; you ship.
• Build the application layer that wraps Lilly's AI models into reliable, cohesive workflows for biotech customers.
• Drive features end-to-end. Take a fuzzy requirement, weigh the tradeoffs, and ship something that works.
• Stay deep in the code. This is a build role, not a review role.
• Contribute to the engineering bar-code review, testing, release process, on-call. Hold the standards we set.

Lift the team

• Mentor the engineers around you. Make them better at the job, not just better at this codebase.
• Partner with PM and design on features. Speak up early when something feels off in the spec or the scope.
• Help interview engineers as the team grows. Hold the bar.
• Spot the things nobody owns and either pick them up or flag them clearly.

Operate effectively inside a large company

• Navigate enterprise infrastructure, security, and compliance requirements without disrupting development progress.
• Work with Lilly IT and internal platform teams to leverage existing capabilities rather than rebuild them.
• Join customer conversations when it helps. You can hold your own technically with a counterpart on the other side.

Minimum Requirements

• Education: Bachelor's degree in Computer Science, Engineering, or a related field.
• 5+ years of software engineering experience, with a track record of shipping software that real customers used and relied on.
• Experience as a senior engineer on a product team-ideally a small one.
• Qualified applicants must be authorized to work in the United States on a full-time basis. Lilly will not provide support for or sponsor work authorization or visas for this role, including but not limited to F-1 CPT, F-1 OPT, F-1 STEM OPT, J-1, H-1B, TN, O-1, E-3, H-1B1, or L-1

Additional Skills/Preferences
Technical depth

• Strong full-stack fundamentals. You're comfortable owning a feature from database schema to UI and have an opinion about each layer.
• Solid API design and integration experience. You know how to build systems that connect things cleanly.
• Real frontend craft: you can design and ship interfaces that feel right, not just functional. You sweat the empty states and the error states.
• Cloud experience and comfort with modern deployment practices.
• Enough familiarity with AI/ML to make good integration decisions. You don't need to be a data scientist, but you need to understand what you're wrapping and why it matters.
• Always learning. You want the why behind an ask, not just the what, and you don't let momentum decide a solution for you.
• Hands-on experience building LLM-powered features. You understand the practical challenges: reliability, evals, context management, and when not to use AI.
• Comfortable with AI-assisted development tools (Cursor, Claude Code, etc.). You know how to get the most out of them.

Product instincts

• You think about the user, not just the system. You've built software that external customers actually paid for and relied on.
• You've simplified complex backend capabilities into clean, usable product experiences.
• You ask "what problem are we solving?" before "how do we build it?"
• You talk product with a PM, not just specs. You'll raise "wait, why are we building this?" when it matters.
• Focused on delivering business value, not just shipping features. You'll work directly with internal stakeholders and customers when it helps the team.

Startup mentality

• You've worked in environments where the roadmap wasn't fully defined and the team was small, and you thrived.
• You unblock yourself and figure things out. You don't wait for a spec or hand-holding.
• You create structure and process when needed, but you know when to skip it.
• You take ownership broadly. If something isn't working, you fix it rather than wait for someone else to.
• Startup experience matters here more than big-tech tenure.

How you work

• You bring judgment to your work. You speak up early when something looks off and update fast when you're wrong.
• Low ego, high standards. You'll learn from a more junior engineer who knows the area better, and you'll push back firmly when you don't agree.
• You communicate clearly across technical and non-technical audiences.

Additional Preferences

• Experience in life sciences, pharma, or health tech.
• Background building B2B SaaS products.
• Prior experience at a startup, or as an early engineer in an internal startup within a larger company.

Why This Role
Lilly has built genuinely differentiated AI capabilities for drug discovery. The gap is product: turning that science into something a biotech startup can access, onboard, and build with. That's what this team is about.
You'll be one of the early engineers on a small team. The codebase is young, the practices are forming, and your work shapes them. You'll have real ownership, a short decision chain, and work that matters. The product you help ship can affect how medicines get discovered and developed. That's not a line in a pitch deck-it's the actual job.
Lilly is dedicated to helping individuals with disabilities to actively engage in the workforce, ensuring equal opportunities when vying for positions. If you require accommodation to submit a resume for a position at Lilly, please complete the accommodation request form (https://careers.lilly.com/us/en/workplace-accommodation) for further assistance. Please note this is for individuals to request an accommodation as part of the application process and any other correspondence will not receive a response.
Lilly is proud to be an EEO Employer and does not discriminate on the basis of age, race, color, religion, gender identity, sex, gender expression, sexual orientation, genetic information, ancestry, national origin, protected veteran status, disability, or any other legally protected status.
Our employee resource groups (ERGs) offer strong support networks for their members and are open to all employees. Our current groups include: Africa, Middle East, Central Asia (AMECA), Black Employees at Lilly (BE@Lilly), Chinese Culture Network (CCN), EnAble, Evolve, Lilly Indian Network (LIN), Organization of Latinx at Lilly (OLA), Pride (LGBTQ+ Allies), Veterans Leadership Network (VLN) and Women's Initiative for Leading at Lilly (WILL).
Actual compensation will depend on a candidate's education, experience, skills, and geographic location. The anticipated wage for this position is
$153,000 - $246,400
Full-time equivalent employees also will be eligible for a company bonus (depending, in part, on company and individual performance). In addition, Lilly offers a comprehensive benefit program to eligible employees, including eligibility to participate in a company-sponsored 401(k); pension; vacation benefits; eligibility for medical, dental, vision and prescription drug benefits; flexible benefits (e.g., healthcare and/or dependent day care flexible spending accounts); life insurance and death benefits; certain time off and leave of absence benefits; and well-being benefits (e.g., employee assistance program, fitness benefits, and employee clubs and activities).Lilly reserves the right to amend, modify, or terminate its compensation and benefit programs in its sole discretion and Lilly's compensation practices and guidelines will apply regarding the details of any promotion or transfer of Lilly employees.
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