Jettro is a Fellow at Luminis in Amsterdam, specialized in Search. He has a strong background in the Java eco system. He also has experience in the front-end with React and Angular. These days Jettro is mainly involved with the elastic stack and he is learning about and experimenting with Machine Learning. Combining Machine Learning with Search to solve one of the hardest search problems, named ranking, is what keeps him going. Jettro believes in the vision of Luminis that: Knowledge is the only thing that increases by sharing. Therefore he writes blogs, gives trainings and presents at a number of meetups and conferences.