Yarn & Materials Developer New England, United Kingdom

Help shape the future of Gymshark Seamless innovation.

At Gymshark, great seamless products start with exceptional yarns, materials, and technical innovation. We're looking for a knowledgeable and detail-oriented
Yarn & Materials Developer to support the end-to-end development and industrialisation of seamless yarns, knit structures, and material platforms, from initial concept through to bulk production.

This role is critical in ensuring our seamless products meet the highest standards of performance, quality, durability, fit, innovation, and sustainability while supporting the successful delivery of our seasonal collections. You'll work closely with Seamless Technical Development, Knit Programming, Product Development, Design, Colour, Sourcing, Quality, yarn suppliers, seamless manufacturing partners, and machine technicians to develop industry-leading seamless products that help strengthen Gymshark's position as a global leader in performance apparel.

As a
Yarn & Materials Developer
, you'll play a key role in translating product vision into technically feasible, commercially scalable, and performance-led seamless products, ensuring development milestones are achieved on time and to the highest standard.

Key responsibilities include:

Developing and industrialising seamless yarns, knit constructions, and material platforms across multiple product categories.

Translating consumer needs such as sculpting, support, compression, softness, breathability, opacity, sweat management, and comfort into innovative yarn and knit solutions.

Supporting fibre selection, yarn specification, elastane construction, covering methods, feeder allocation, yarn pathing, and machine set-up decisions to achieve desired performance outcomes.

Collaborating closely with Seamless Technical Development, Knit Programming, Product Development, Design, Colour, and Sourcing teams throughout the development process.

Partnering with yarn suppliers and seamless manufacturing partners to develop proprietary and commercially scalable seamless material solutions.

Supporting the development of seamless knit architectures including rib, mesh, jacquard, tuck, float, plating, engineered ventilation, waistbands, under bust structures, and body-mapped compression zones.

Building supplier capability through technical collaboration, performance reviews, and continuous improvement initiatives.

Supporting seamless-specific testing and validation programmes, including stretch and recovery, compression, opacity, dimensional stability, abrasion resistance, pilling, colour fastness, and wash durability.

Interpreting laboratory, wear trial, and supplier testing data and converting findings into clear technical action plans.

Integrating sustainability considerations into yarn, material, and product development to improve environmental performance without compromising product quality or functionality.

Contributing to commercial engineering decisions involving yarn cost, stitch complexity, machine time, lead times, and manufacturing efficiency.

Maintaining accurate technical documentation, including yarn specifications, knit construction records, test reports, supplier capability data, and development libraries.

Managing and developing seamless yarn, stitch architecture, body-mapping, and material platform libraries.

Supporting the creation of Gymshark-owned seamless platforms, proprietary knit structures, technical claims, and supplier-exclusive developments.

• Minimum of 3 years' experience in material development, yarn development, seamless development, performance fabric development, or related technical product development.
• Strong technical knowledge of seamless materials, fibres, yarns, and knit constructions.
• Good understanding of seamless circular knitting technology, preferably Santoni or equivalent machinery.
• Knowledge of yarn covering methods, yarn draw-in processes, feeder allocation, plating, yarn pathing, and yarn tension principles within seamless circular knitting.
• Ability to assess how fibre composition, yarn selection, stitch architecture, elastane construction, and machine settings influence…