Rafal Kuc is a born team leader and software developer. He currently works as a consultant and software engineer at Sematext Group, Inc., where he concentrates on open source technologies such as Apache Lucene and Solr, Elasticsearch, and Hadoop stack. He has more than 14 years of experience in various software branches-from banking software to e-commerce products. He focuses mainly on Java but is open to every tool and programming language that will make the achievement of his goal easier and faster. Rafal is also one of the founders of the solr.pl site, where he tries to share his knowledge and help people with the problems they face with Solr and Lucene. He is also a speaker at various conferences around the world, such as Lucene Eurocon, Berlin Buzzwords, ApacheCon, Lucene Revolution, and DevOps Days. Rafal began his journey with Lucene in 2002, and it wasn't love at first sight. When he came back to Lucene in late 2003, he revised his thoughts about the framework and saw the potential in search technologies. Then, Solr came along and that was it. He started working with Elasticsearch in the middle of 2010. Currently, Lucene, Solr, Elasticsearch, and information retrieval are his main points of interest. Rafal is also the author of Apache Solr 3.1 Cookbook, and the update to it, Apache Solr 4.0 Cookbook, both published by Packt Publishing. He also authored Elasticsearch-related books, ElasticSearch Server and its second edition, and the first and second editions of Mastering ElasticSearch, all published by Packt Publishing. This book is a second update to the first book I ever wrote- Apache Solr 3.1 Cookbook, Packt Publishing. Again, similar to Apache Solr Cookbook 4.0, Packt Publishing, what meant to be an update turned out to be almost a complete rewrite because of the pending release of Solr 5.0 and the changes to Solr itself. Between Solr 4.0 and 5.0, there were a lot of changes and additions to Solr, and I know I didn't manage to gather them all in the recipes that are present in the book you are holding. However, I hope that if you are either using Solr 4.x or Solr 5.0, this book will help you overcome some common problems and will push your knowledge about Solr a bit further.