To my advisor Marcus Poggi, for all the opportunities, teaching, support and advices throughout my academic and professional life. To my friend and co-advisor Bruno Flach, for giving me the chance to pursue my PhD while working at IBM, and for all the academic collaboration, inspiration and fun we've had during this journey. To the examination committee, for the various valuable contributions during the defense. To my IBM friends and co-workers, for all the support, fun and inspiration throughout these years. To my friends Hélio, Fábio, Cândida, Carlos, Stephanie, Felipe, Gisele, Valente and Antony, for being my carioca family, and for all the love, support and joy you share with me, Aurélia, Felipão and everyone close to us. To my friends Daniel and César, for their friendship in all key moments of my life, specially in the early years of our arrival in Rio. Thanks for everything my friends, you were really important for this moment to be possible. To my father Carlos, for all the support you dedicate to me and my brothers from childhood to adult life, and to be a model of honesty and integrity. To my family, for being the best family I can imagine, giving me the basis to be the person I am today. To my mom Armênia, to have dedicated her life to her sons, teaching us every good part of our personalities. Mom if this moment is a victory, it is yours more than mine, you gave everything to us, I hope we can return all you deserve to provide you with a life full of joy. Love you mom! To the love of my life, my wife Aurélia, for being the source of my happiness, for all the love you give to me and our son, for having supported me in all difficult moments and always pointed out the right decision for every problem, for giving me my most precious gift in life, our son Felipe, and for being this incredible, beautiful, dedicated and wise mom. My love, you are more than I could ever dreamed of, my admiration and love for you is infinite, I'm immensely lucky and happy to build a family by your side! To my son Felipe, for being such a great son and human being, for teaching me every day to be a better father and person, for all the love you give to me, and for simply be part of my world and the meaning of my life. My son, I love you in the way that I can't explain, I'm sorry for the lost moments while I was working in this PhD, your comprehension and affection were fundamental to me to have finished this journey successfully, now it is time to fulfill my promise and build a game with you!