front matter
I’ve known Alexey for more than six years. We almost worked together at the same data science team in a tech company in Berlin: Alexey started a few months after I left. Despite that, we still managed to get to know each other through Kaggle, the data science competition platform, and a common friend. We participated on the same team in a Kaggle competition on natural language processing, an interesting project that required carefully using pretrained word embeddings and cleverly mixing them. At the same time, Alexey was writing a book, and he asked me to be a technical reviewer. The book was about Java and data science, and, while reading it, I was particularly impressed by how carefully Alexey planned and orchestrated interesting examples. This led soon to a new collaboration: we coauthored a project-based book about TensorFlow, working on different projects from reinforcement learning to recommender systems that aimed to be an inspiration and example for the readers.