The rapid ongoing digital transformation creates new opportunities to generate value but also challenges companies in the manufacturing industry to adapt to the recent changes. Moreover, committing to sustainability is essential to maintain competitive advantages, build a more resilient company, and manage increasing societal demands and regulations. Referred to as a "twin transition", the digital transformation can positively impact firms' commitments to environmental sustainability. This paper explores challenges that small technology solution providers face on their path toward developing sustainable production solutions for their manufacturing customers. An empirical study was conducted in an industrial cluster of small and medium-sized companies (SMEs) providing innovative, tailor-made production technology solutions to manufacturing companies. As a result, a collaborative process model was suggested for such SMEs to overcome internal and external barriers to obtaining sustainability, thus better supporting the manufacturing companies, i.e., their customers, to strive towards more sustainable production.