Combining microservices and software product line engineering (SPLE) is a challenge in variability management. This paper proposes a solution to that challenge by re-engineering existing webshop systems into a product line application. We first perform feature identification to analyze the features of subject systems. We introduce a mechanism that models the variability and designs a software product line architecture based on existing features. We use a UML diagram with the UML-DOP profile to abstract microservice variability in SPLE. Then, a transformation into a product line application is conducted to generate running applications based on selected features. We utilize a preliminary framework of microservice variability based on delta-oriented programming. © 2020 ACM.