Chief Technology Officer

Bloomineral is a Marble Portfolio Company

About Marble

Marble is a climate tech venture studio. We partner with scientists, engineers, and operators to create companies solving hard climate problems in the world's largest industries. Our first
13 companies
are building transformative products across energy, industry, agriculture, and climate resilience. 100% have been successful in raising follow-on to date. We are looking to partner with exceptional individuals to create our next venture.

About Bloomineral

At Bloomineral, we transform CO₂ into solid minerals through large-scale biomineralization. Our macroalgae grow ultra-pure, carbon-negative calcium carbonate that permanently stores CO₂ and directly replaces mined limestone across various industries. The material is chemically identical to what industries already use (in cosmetics, paint, adhesives, agriculture, construction, etc), seamlessly integrating into existing formulations, but with higher purity, brightness, and fineness.

We are seeking a
Chief Technology Officer (CTO)
to lead our technology and product development strategy. This role will involve guiding our technology from the early development stages to a market-ready agricultural biotech product. As an early-stage startup with significant growth potential, this position offers the chance to make a real impact in the world and help shape the work culture from day one.

You will join an experienced CEO with a PhD in Geochemistry and a stellar track record as a postdoctoral researcher in leading institutions around the World.

Start date target / latest:
October 2026

Mission/role summary:
Lead the long-term vision, technical strategy, industrialization roadmap, and scaling of the biomineralization platform. Act as a senior technical leader (potential co-founder) capable of bridging science, process, commercialization, and scale-up execution.

Key Responsibilities

• Define and lead the technical roadmap from pilot stage to industrial deployment, ensuring robustness, cost competitiveness, and scalability.
• Oversee all R&D, process engineering, scale-up, automation, operations, and technology risk.
• Own and validate technology choices (reactor designs, process flows, instrumentation, process intensification).
• Drive cross-functional integration: aligning R&D, analytical / geochemistry, engineering, operations, QA, and commercialization.
• Identify and mitigate key technical risks; lead failure root-cause investigations and corrective strategies.
• Define and oversee technology transfer to manufacturing / industrial partners or internal scale plants.
• Build and lead the technical team: recruiting, mentoring, and structuring functions for growth.
• Participate actively in fundraising, technical due diligence, investor engagements, and IP / patent strategy.
• Ensure that technical decisions align with business goals, cost models, margins, and carbon credit/certification outcomes.
• Keep abreast of scientific and technological advances in biomineralization, carbon removal, reactor engineering, and adjacent fields.

Requirements / Profile

• PhD or equivalent experience in bioprocessing, environmental engineering, chemical engineering, biochemical engineering, or a related field.
• Strong track record (10+ years or equivalent) in developing, scaling, and industrializing complex bio/chemical or mineralization systems.
• Experience in bridging lab-scale innovation to pilot / industrial scale, with a deep understanding of process engineering, automation, reliability.
• Proven leadership and team management ability in R&D / engineering contexts.
• Strong strategic thinking: ability to prioritize technical investments under constraints.
• Experience working with external stakeholders: investors, partners, certification bodies, and manufacturing partners.
• Excellent communication skills (technical and non-technical), able to act as a technical ambassador for the company.
• Entrepreneurial mindset, comfortable in ambiguity, capable of hands-on leadership in a lean startup environment.
• Understanding of the carbon removal / carbon credit space, MRV, certification, and regulatory constraints is a strong plus.

Job Benefits:

• Our benefits package includes attractive stock options and a competitive salary reflective

of the early stage of the company. We're committed to matching market-rate salaries

after our next major fundraising round.

• Other benefits include flexible schedules, holidays, and paid time off.

EEO Statement:

We are a team of unconventional founders who appreciate the value that diversity has contributed to our own journey. We encourage anyone to apply who may otherwise have reservations due to disabilities (visible or invisible) or unusual life circumstances. As an equal opportunity employer, we will consider all applicants regardless of race, color, religion, sex, sexual orientation, age, gender identity or expression, national origin, disability, or veteran status.