Today’s fashion industry is marked by rapid production, early disposal and low-quality materials, resulting in environmental harm and social injustice. Denim production involves a resource-intensive and extended supply chain with entrenched design practices, leading to substantial pre-consumer waste. To address these issues, emerging design manufacturing techniques hold promise for fostering alternative sustainable fashion ecosystems yet remain largely underexplored by the industry. The current work focuses on 3D weaving, an innovative niche design manufacturing technique that enables the production of near-complete garments, facilitating zero waste and reducing labour-intensive steps at the cut-and-sew stage. Employing a qualitative approach informed by the literature and empirical research with denim industry professionals, this study investigates the potential of this novel design manufacturing technique in the context of systemic change beyond merely introducing technological advancement as an intervention in the existing industry. The analysis reveals four fundamental components: industry-led change, relocalisation, reimagining denim design roles and consumer communication. These key components, synthesised with the literature, are discussed respectively. We illustrate how the niche design manufacturing technique can shape novel fashion ecosystems by providing an exemplary concept which concerns the collaborative establishment of a small-scale local supply chain for 3D woven denim garments. Through this example, we aim to ignite discussions on a further reimagining of the fashion industry, utilising similar alternative lenses that prioritise sustainability over ultra-speed, high efficiency and mass production in alignment with the United Nations Sustainable Development Goals 9 (Industry, Innovation and Infrastructure), 12 (Responsible Consumption and Production) and 17 (Partnerships for the Goals).