Codebreaker Labs is building CODEX, the causal data layer for genomics AI.

Roughly 9 billion human variants are possible and less than 0.05% are understood. We edit human cells one nucleotide at a time — primary T cells, other primary cells, fibroblasts, and iPSC-derived models — and measure what each variant actually does, producing causal single-base data for immunology, oncology and rare disease.

We are a seed-stage team in Boulder, Colorado, built by people who helped make genome editing industrial. Small lab, real ownership, work that shows up directly in the data.

The Opportunity

Codebreaker is building a modern functional genomics research engine to connect human genetic variation to cellular function at scale. We are looking for an enthusiastic molecular biology scientist who is excited about hands-on experimental work in human cell culture and genome engineering, and who brings the energy, judgment, and ownership mindset it takes to contribute to a seed stage.

This is a hands-on laboratory scientist role. You will execute genetic screening, cell engineering, and phenotyping workflows across challenging human cell models, including primary T cells, other primary cells, fibroblasts, and iPSC/iPSC-derived systems. Working closely with Senior Scientists and the Director of Biology, you will contribute to experimental planning, execution, troubleshooting, and data analysis while developing increasing independence in experimental design and interpretation.

You will partner closely with computational biology and machine learning colleagues and use modern AI tools as part of your daily scientific workflow to improve the quality, speed, and scope of what the team can accomplish. You should genuinely enjoy experimental work, take ownership of problems, prioritize what matters most, move quickly, and put in the extra effort when an experiment or troubleshooting requires it.

What You’ll Do

• Execute high-throughput functional genomics programs using CRISPR and related perturbation technologies in human cells.
• Culture and execute workflows for technically demanding human cell systems—including primary T cells, other primary cells, fibroblasts, and iPSC/iPSC-derived models—according to established experimental plans.
• Apply phenotyping approaches, ideally including single-cell RNA-seq and other single-cell or multi-omic readouts, flow cytometry, and functional cellular assays.
• Identify opportunities to improve established assays and workflows and contribute to their implementation.
• Contribute to experimental planning and data analysis and work with computational colleagues to ensure data are accurately structured and annotated.
• Perform careful experimental execution, troubleshooting, quality control, and documentation, escalating complex issues appropriately.
• Maintain detailed and reproducible documentation of experiments, protocols, and results using ELN/LIMS and other appropriate systems.
• Use AI-enabled tools where appropriate to support experimental planning, execution, documentation, and data analysis.
• Present experimental results and progress updates to the research team and contribute to internal documentation and, where appropriate, publications and external presentations.
• Collaborate closely with Senior Scientists, research associates, and computational colleagues to support research program objectives.
• Prioritize the most important task in front of you, ask for more when the queue is light, and be willing to stay a little later when an experiment needs it—because you want to see it done right.

What We’re Looking For

• MS or PhD in immunology, molecular biology, genomics, cell biology, or a related field, with relevant hands-on laboratory research experience.
• Hands-on experience in mammalian cell culture, ideally with challenging cell models (e.g., primary cells and/or iPSCs), and with CRISPR-based gene editing or related screening technologies—or strong readiness to develop this expertise quickly.
• Familiarity with phenotypic characterization techniques such as flow cytometry, sequencing-based assays, or functional immune assays.
• Solid quantitative and analytical skills; comfortable working with structured datasets, standard data analysis tools (e.g., R, Python), and AI-assisted analysis tools—or motivated to build these skills.
• Strong attention to detail, record-keeping, and communication skills.
• Ability to work both independently on well-defined tasks and collaboratively within a team-based research environment.
• Strong work ethic and eagerness to get things done. You show up ready to prioritize the most important task in front of you, move quickly, and are willing to put in extra time when an experiment or deadline calls for it.

Especially Valuable

• Prior experience with human cell culture (e.g., primary cells or iPSCs).
• Exposure to high-throughput or pooled screening methodologies.
• Familiarity with sequencing-based genomics platforms (e.g., single-cell or bulk platforms such as 10x Genomics).
• Prior experience in a biotech or academic research lab setting, and eagerness to bring that same hands-on energy to a fast-moving startup team.

Why Codebreaker

This role offers real hands-on ownership from day one. You will help build, run, and troubleshoot the cell systems, assays, and workflows our science depends on—work that shapes not just your own experiments, but how the whole biology team operates as we scale.

The right person will have room to grow quickly into more independence and responsibility. If you are happiest at the bench, energized by hard problems, and excited to help build a lab from the ground up, we would like to meet you.

Benefits

Competitive benefits package. Full details are shared during the interview process.

Equal Opportunity

Codebreaker Labs is an equal opportunity employer. We consider all qualified applicants without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, protected veteran status, or any other characteristic protected by law.