Improving flexibility in the manufacturing industry has always been a challenge. Workers at assembly lines have to cope with a flexible and rapidly changing production process. To meet these challenges, an assistance system is proposed that is used during the production process to provide workers with near real-time instructions regarding changes to the production process. This enables the development of a versatile production range that includes large and small series, as well as customised solutions. An example of an automotive assembly line is used to demonstrate the feasibility of the system. In conclusion, the proposed system advocates an in-line qualification process for workers that would facilitate a paradigm shift towards agile manufacturing and lead to a significant increase in resilience.