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<html><head></head><body><h3><strong>About Cocoon</strong></h3>
<p>Cocoon is driving the circular economy between steel and cement by turning steel slag into a low-carbon cement substitute.</p>
<p>We're backed by leading climate and hardware tech investors, including 2150, Brick &amp; Mortar, Gigascale, Wireframe, and Celsius Industries. In under two years, we've gone from concept to deploying our breakthrough technology at one of the largest steel producers in the US.</p>
<p>We’re doubling the team in 2026 to tackle the next wave of technical challenges as we scale towards our first permanent production plant.&nbsp;</p>
<h3>The Role</h3>
<div>We’re looking for a Science Intern to support our researchers, manage day-to-day lab workflow, and operate a wide range of analytical equipment with help from our experienced team. You’ll help prepare samples in our mortar and concrete labs and learn to run characterisation methods, including XRD, PSA, ICP-OES, TGA, and isothermal calorimetry.</div>
<p>By keeping data flowing reliably, you’ll play a central role in enabling Cocoon to accelerate research and development.</p>
<h3>Responsibilities</h3>
<h4>Laboratory Operations</h4>
<ul>
<li>Supporting researchers with their critical workstreams.</li>
<li>Sample preparation for mortar and concrete testing</li>
<li>Sample preparation for material characterisation.</li>
<li>Conducting material characterisation work in the lab (XRD, PSA, ICP-OES, TGA, isothermal calorimetry).</li>
<li>Ensuring the lab is tidy and the inventory is up to date.</li>
<li>Assisting QC processes from industrial trials.</li>
</ul>
<h4>Data Management&nbsp;</h4>
<ul>
<li>Archiving material characterisation data effectively so all users can access it.</li>
<li>Data generation and cataloguing on Cocoon’s mortar and concrete databases.</li>
<li>Generating data to support the commercial activities of the business.</li>
</ul>
<h4>You’ll Succeed In This Role If You…</h4>
<ul>
<li>Have made mortar or concrete samples before</li>
<li>Bring experience in material characterisation</li>
<li>Are comfortable organising large data sets</li>
<li>Have an eye for detail and follow processes to the letter</li>
<li>Thrive in a fast-moving, hands-on laboratory environment.</li>
</ul>
<h4>What We Offer</h4>
<ul>
<li>A central role in scaling Cocoon’s laboratory capabilities.</li>
<li>The opportunity to support formal research advancement across the team.</li>
<li>The chance to contribute data directly to demo-plant development and commercial work.</li>
</ul>
<h4>Apply Now</h4>
<div>If you’re excited about generating high-quality data, supporting critical research, and helping Cocoon scale towards demo-plant deployment, we’d love to hear from you.</div></body></html>

Science Intern

<html><head></head><body><h3>About Cocoon</h3>
<p>Cocoon is driving the circular economy between steel and cement by turning steel slag into a low-carbon cement substitute.</p>
<p>We're backed by leading climate and hardware tech investors, including 2150, Brick &amp; Mortar, Gigascale, Wireframe, and Celsius Industries. In under two years, we've gone from concept to deploying our breakthrough technology at one of the largest steel producers in the US. Steel and cement account for nearly 15% of global CO₂ emissions, and decarbonising these industries requires completely new approaches to mix design, testing, and implementation.</p>
<div>We’re now building our in-house concrete capability so we can qualify SCMs, validate performance against industry standards, and support deployment of our technology at pilot and demo-scale. To do this, we’re establishing a fully equipped concrete laboratory in London and we’re looking for a Concrete Technician to help make it happen.</div>
<h3>The Role</h3>
<p>We’re looking for a Concrete Technician to support the design, mix, test, and manage concrete across an extensive experimental programme. You’ll help establish our concrete lab, assist with equipment commissioning, and contribute to SOPs development, delivering mechanical and durability testing to ASTM, BSI, and related standards</p>
<p>You’ll support the full lifecycle of concrete development, from mix design and batching, through casting and curing, to compressive strength and durability testing while keeping meticulous data records and maintaining a safe, well-organised laboratory. You’ll also support field trials, coordinate external testing, and provide experimental results to our research and commercial teams.</p>
<p>This role is hands-on, varied, and central to Cocoon’s ability to qualify SCMs, validate performance, and scale towards real-world deployment.</p>
<h3>Responsibilities</h3>
<h4>Concrete Development &amp; Testing</h4>
<ul>
<li>Prepare and trial concrete mix formulations across the experimental matrix (SCM replacement, admixtures, w/b ratios) to ASTM C1709 and BSI Flex 350.</li>
<li>Plan batching schedules, specimen numbers, test timelines, and weekly execution plans.</li>
<li>Support optimisation of mix proportions and help troubleshoot workability, flash setting, segregation, and strength issues.</li>
<li>Operate the mixer and conduct fresh property tests (slump, density, air content, bleeding).</li>
<li>Record batch data (temperature, timings, slump, w/b) and maintain full QA/traceability.</li>
<li>Cast cubes and cylinders; manage curing tanks, curing regimes, and specimen conditioning.</li>
<li>Perform compressive and flexural strength testing at 7, 28 and long-term ages.</li>
<li>Prepare and run durability tests (RCPT, bulk resistivity, water absorption, sorptivity, permeability, drying shrinkage, sulfate resistance, carbonation depth).</li>
</ul>
<h4>Laboratory Setup, Management &amp; Safety</h4>
<ul>
<li>Assist in preparing and maintaining SOPs for all concrete lab processes and support commissioning of existing equipment.</li>
<li>Support identification, procurement, and installation of additional equipment required for the testing regime.</li>
<li>Support baselining testing of cement and benchmark materials.</li>
<li>Maintain calibration, servicing, and safe operation of all equipment.</li>
<li>Manage consumables (PPE, mould oil, aggregates, cement) and keep the lab organised and compliant.</li>
<li>Ensure all risk assessments are in place and adhered to.</li>
</ul>
<h4>Data, Collaboration &amp; External Coordination</h4>
<ul>
<li>Maintain digital logs, record raw data, and align outputs with current data storage methods.</li>
<li>Process and analyse test results; prepare technical reports and summaries, and present data for internal reviews, meetings, and partner updates.</li>
<li>Support training of team members in SOPs, mixing, fresh testing, and equipment use.</li>
<li>Coordinate outsourcing for tests not done in-house and manage samples, logistics, and external data integration.</li>
<li>Support small-scale field trials and demonstration pours, including onsite testing.</li>
</ul>
<h3>You’ll Succeed In This Role If You…</h3>
<ul>
<li>Have hands-on experience in concrete testing, materials laboratories, or construction materials research.</li>
<li>Are confident working to ASTM, BS EN, and other standards.</li>
<li>Enjoy practical, repetitive experimental work and take pride in process discipline.</li>
<li>Communicate clearly and maintain rigorous documentation.</li>
<li>Thrive in a fast-moving environment with changing priorities.</li>
<li>Are proactive, organised, and comfortable maintaining and operating a lab space.</li>
</ul>
<h3>What We Offer</h3>
<ul>
<li>A chance to build Cocoon’s concrete lab from the ground up.</li>
<li>The opportunity to generate data that feeds directly into demo-plant development.</li>
<li>Hands-on experience with a wide range of mechanical and durability tests.</li>
<li>Collaboration with researchers, commercial teams, and external laboratories.</li>
<li>Clear growth opportunities as our concrete and materials programmes scale.</li>
<li>A competitive salary, company pension, £600 annual Learning &amp; Development budget, 28 days' annual leave.</li>
</ul>
<h3>Apply Now</h3>
<div>If you’re excited about developing and testing low-carbon concrete — and helping Cocoon scale towards real-world deployment — we’d love to hear from you.</div>
<div>&nbsp;</div></body></html>

Concrete Technician

<html><head></head><body><h3><strong>About Cocoon</strong></h3>
<p>At Cocoon, we’re developing low-carbon construction materials for the builders of tomorrow. Delivering our technology at demo-plant scale requires extensive hands-on engineering work: building, installing, commissioning, and operating equipment that enables testing and material generation in real-world conditions.</p>
<p>This role is central to delivering and scaling our technology. You’ll drive implementation and delivery for the engineering team, building test rigs, installing equipment at partner sites, and supporting trials in the UK and USA as we scale towards building a permanent plant.</p>
<h3>The Role</h3>
<p>We’re looking for an Engineering Technician to build, install, and operate prototype equipment and test rigs that support Cocoon’s R&amp;D and material generation programmes. You’ll work closely with engineers, scientists, and operations teams to deliver trials safely, on time, and to specification, often in challenging industrial environments.</p>
<p>This is a highly practical, travel-heavy role involving mechanical build, electrical wiring, hydraulics, commissioning, troubleshooting, and trial execution. You’ll spend significant time travelling, supporting test campaigns, and installing equipment at partner locations in the UK, Europe, and the US.</p>
<h3>Responsibilities</h3>
<h4>Test Rigs, Equipment, and Trials</h4>
<ul>
<li>Build test rigs and prototype equipment to agreed designs, timelines, and quality standards.</li>
<li>Install, commission, and operate equipment at Cocoon test sites and partner facilities in the UK and abroad.</li>
<li>Carry out tests under the direction of a test engineer and report findings.</li>
<li>Upgrade and modify test rigs with new hardware, controls, instrumentation, or mechanical components.</li>
<li>Suggest process and hardware improvements and be a key source of information for the R&amp;D and process engineering teams from on the ground running of our system.</li>
<li>Support extended test campaigns in the UK and overseas, including driving 3.5-tonne Luton vans, completing risk assessments, and working outdoors in challenging industrial environments.</li>
</ul>
<h4>Mechanical, Electrical and Workshop Work&nbsp;</h4>
<ul>
<li>Perform mechanical, hydraulic, and pneumatic assembly of prototype equipment.</li>
<li>Wire automation cabinets, sensors, actuators, pumps, and 3-phase systems.</li>
<li>Read and interpret manufacturing drawings, wiring diagrams, and process diagrams.</li>
<li>Carry out light machining and fabrication (cutting, drilling, grinding, welding, bending, pipe joining).</li>
<li>Create components using additive manufacturing techniques.</li>
<li>Order service parts, manage workshop organisation, and support general site readiness.</li>
</ul>
<h3>You’ll Succeed In This Role If You…</h3>
<ul>
<li>Have extensive, hands-on experience as an engineering technician in a related industry.</li>
<li>Are confident with mechanical build, basic electrical installation, hydraulics, and troubleshooting.</li>
<li>Can work independently on targets while collaborating closely with engineers and scientists.</li>
<li>Are proactive, dependable, safety-conscious, and driven to solve problems.</li>
<li>Are willing and able to travel extensively and work extended hours during test campaigns.</li>
</ul>
<h4>Bonus qualities</h4>
<ul>
<li>Knowledge of industrial automation, instrumentation, and PLCs</li>
<li>Welding qualifications, especially TIG for stainless steel</li>
<li>Forklift qualification or experience operating heavy equipment.</li>
<li>Electrical installation or wiring qualifications.</li>
<li>Experience working with foundries or high-temperature process equipment.</li>
</ul>
<h3>What We Offer</h3>
<ul>
<li>A hands-on role at the centre of Cocoon’s engineering and scaling journey.</li>
<li>The opportunity to work on first-of-a-kind test rigs and prototype equipment.</li>
<li>Extensive travel and exposure to world-class industrial partners and test facilities.</li>
<li>Clear progression opportunities toward workshop lead, supervisor, or test engineer roles.</li>
<li>A mission-driven team working to support the transition to Net Zero.</li>
<li>Competitive salary, company pension, £600 annual Learning &amp; Development budget, 28 days' holiday.</li>
</ul>
<h3>Apply Now</h3>
<div>If you’re excited by building hardware, running trials, and spending time in the field turning engineering designs into reality, we’d love to hear from you.</div></body></html>

Engineering Technician

<html><head></head><body><h3><strong>About Cocoon</strong></h3>
<p>Cocoon is driving the circular economy between steel and cement by turning steel slag into a low-carbon cement substitute.</p>
<p>We're backed by leading climate and hardware tech investors, including 2150, Brick &amp; Mortar, Gigascale, Wireframe, and Celsius Industries. In under two years, we've gone from concept to deploying our breakthrough technology at one of the largest steel producers in the US.</p>
<p>We’re doubling the team in 2026 to tackle the next wave of technical challenges as we scale towards our first permanent production plant.&nbsp;</p>
<h3>The Role</h3>
<p>We’re looking for a Business Operations (BizOps) Intern to help keep our operations running seamlessly — someone who takes pride in keeping things organised, efficient, and well-communicated. You’ll be the first point of contact for many of the day-to-day details that keep our office, lab, and team running safely and effectively.</p>
<p>As part of Cocoon, you’ll learn about scaling a technology startup, build new systems and processes, and support our expert team as we rapidly grow the business. The role will be challenging; you’ll learn fast, execute business-critical processes and systems, and support the team as we scale towards our first commercial plant, giving you the chance to build your professional experience and contribute to decarbonising two of the most carbon-intensive industries in the world.</p>
<h3>Responsibilities</h3>
<div>
<h4>Business Operations</h4>
<ul>
<li>Help keep the business running smoothly through maintaining and developing key monthly processes across finance, people, and company operations</li>
<li>Find ways to improve how we operate using better systems, automation, and AI tools</li>
<li>Troubleshoot day-to-day issues in the office and workshop to keep things running without a hitch</li>
<li>Help bring the marketing strategy to life by producing content with support from the team.</li>
<li>Jump into any other functional area as needed to support the wider team, e.g. recruitment, sales, and other business priorities.</li>
</ul>
<h4>Finance &amp; Logistics</h4>
<ul>
<li>Coordinate team travel and logistics, including flights, accommodation, and transport</li>
<li>Support ordering, inventory, deliveries, returns, and team expense processing</li>
<li>Support wider finance tasks when needed, including supplier setup, reconciliations, and month-end processes</li>
<li>Work with suppliers and contractors to ensure reliable and cost-effective services</li>
</ul>
<div><strong>Office, People, &amp; Culture</strong></div>
<ul>
<li>Organise training sessions and support onboarding for new team members.</li>
<li>Help create a welcoming, tidy, and positive office environment.</li>
<li>Act as the main point of contact for utilities, building access, and office security</li>
<li>Help manage key health and safety tasks, including supplies, checks, and records.</li>
<li>Organise team lunches and socials to support a positive team culture.</li>
<li>Ensure the team always has what they need, including PPE, lab supplies, and office essentials.</li>
</ul>
</div>
<h4>You’ll Succeed In This Role If You…</h4>
<ul>
<li>Want to build a career in climate technology and feel energised by our mission</li>
<li>Are proactive and happy to chase loose ends without being asked</li>
<li>Want to work across the entire business and jump into different areas of the company</li>
<li>Pick up new software quickly, with a hacker mindset for combining tools and processes</li>
<li>Are highly organised, with strong attention to detail</li>
</ul>
<h4>What We Offer</h4>
<ul>
<li>The chance to build your career in climate tech at a fast-growing startup</li>
<li>End-to-end experience of startup operations, including the unglamorous tasks that help the company move faster.</li>
<li>Opportunities to improve systems using automation and AI</li>
<li>A supportive, ambitious team and a great office culture</li>
</ul>
<h4>Apply Now</h4>
<div>If you’re excited about building the foundations of a net-zero future and helping the team stay organised and effective, we'd love to hear from you.<br><br>Please note: this role is full-time and starts ASAP, and is therefore unsuitable for current students graduating after April 2026.</div></body></html>

Business Operations Intern

<html><head></head><body><div><strong>About Cocoon:</strong></div>
<div>&nbsp;</div>
<div>Cocoon is on a mission to make steel greener and cement cleaner by creating a low-carbon cement substitute for the builders of tomorrow.</div>
<div>In the next 40 years, the world will witness the construction of double the amount of infrastructure as there is in the world today. Steel and cement are integral to this construction, yet they contribute 15% of global emissions. Cocoon is committed to addressing the climate emergency by decarbonizing these crucial industries, paving the way for a better future for all.</div>
<div>&nbsp;</div>
<div>We are a small and formidable team and growing fast, backed by world-class and global investors in climate, hardware, and industrial decarbonization.</div>
<div>&nbsp;</div>
<div><strong>Apply to Cocoon</strong></div>
<div>&nbsp;</div>
<div>If you are interested in shaping the future of our company and making a meaningful impact in addressing the climate crisis, please apply below.</div>
<div>&nbsp;</div>
<div><strong>How We Work:</strong></div>
<div><br>As a company building hardware we require the team to be in HQ (office/engineering/lab space) the vast majority of time. For some roles, remote working may make sense 1-2 days a week and this is something that can be discussed during the application process. We will always try to accommodate alternative working hours to suit individuals. &nbsp;</div>
<div>&nbsp;</div>
<div><em>Cocoon is an equal opportunities employer. We embrace diversity as a core value and commit to providing equal opportunities for all employees, job applicants, clients, and customers, irrespective of race, ethnicity, gender, sexual orientation, religion, age, disability, or any other protected characteristic. We regularly review our policies, provide training, and encourage open dialogue to ensure a supportive and inclusive workplace for all.</em></div>
<div>&nbsp;</div></body></html>

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Science Intern

Concrete Technician

Engineering Technician

Business Operations Intern

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