Leonardo Ferreira Email & Phone Number

Brasília, Federal District, Brazil

Key Responsibilities- Lead the Backend/ML team- Responsible for each new client's end-to-end ML lifecycle, ensuring all applicable enhancements are applied to maximize Jewel's platform value.- Design and implement new algorithms for user-personalized experiences while enhancing/extending the capabilities of existing algorithms.- Implemented several ETLs and various ML Pipeline enhancements (to train, evaluate, and serve) for offline recommendations.- Using React, Node 18, Looker Studio, and the AntD Design Library, I designed and implemented an analytics portal for our clients.Technologies & Tools:- Languages: Python, Bash, TypeScript- Main Libraries: Pandas, Numpy, Spacy, Scipy, Scikit-learn, Implicit, NLTK, Pytorch, XGBoost, Transformers, etc- Environment: GCP, Docker, Kubernetes- Databases: MongoDB- Tools: Google Analytics (UA/GA4), Google Tag Manager (GTM), Looker Studio

Rio De Janeiro, Rio De Janeiro, Brazil

Overview:- Implemented diverse personalization strategies across mobile and web platforms to enhance user engagement, boost retention, and support the DeliRec creator's economy. Developed and maintained features and recommendations tailored to user preferences.Key Responsibilities:- Designed and implemented end-to-end personalization features, including onboarding processes to minimize the cold-start problem, similar cooking recipe recommendations, intelligent recipe feeds, and popular/trending recipe algorithms.- Developed recommendations for kitchen appliances and utensils based on recipe metadata from various data sources (VTEX, Rakuten, Mosaico).- Maintained an ad-like recipe serving system within the app, integrating multiple sponsored cooking tournaments and campaigns.- Fine-tuned search engine functionality and implemented intelligent recipe tagging using a comprehensive knowledge base and ontologies to enhance user experience in finding suitable recipes.Technologies & Tools:- Languages: JavaScript, Python, Bash, Dart.- Libraries: Pandas, Numpy, Spacy, Scipy, Scikit-learn, Implicit, Pytorch.- Environment: Algolia, Firebase, GCP (Functions, PubSub, Vertex AI, GCS, Schedulers, Compute Engine, BigQuery, Composer, Kubernetes, Artifact Registry, MemoryStore, Cloud CDN, DNS, Load Balancing).- Tools: Prodigy (NLP tasks), Google Analytics (UA/GA4).

Rio De Janeiro, Rio De Janeiro, Brazil

Overview:- Coordinated software development teams and led specialized teams in major telephony operators and a hybrid team responsible for the POS system deployed in over 5,200 stores and played a pivotal role in supporting the management of the development area, providing mentorship and guidance to front-end, back-end, and QA professionals.Key Responsibilities:- Managed software development teams, ensuring successful project delivery and alignment with business goals.- Managed the development and maintenance of the POS system, enhancing operational efficiency across thousands of retail locations.- Supported management by conducting performance reviews, mentoring team members, and providing technical guidance.- Collaborated with stakeholders to define project requirements and ensure alignment with business objectives.Technologies & Tools:Frontend: JavaScript, TypeScript, React, Angular, Vue, Axios.Backend: C#, .NET Core, Microservices.Configuration: SonarQube, Azure DevOps.Infrastructure: Kubernetes, Prometheus, AWS.

Rio De Janeiro Area, Brazil

ChefsClub is the leading platform in Brazil to take people out to eat withdiscounts from 15% to 50% in more than 20 cities and present in the main capitals of Brazil.Responsible for the Technology, Product, and BI teams (15+ people). With this, in addition to ensuringthe continuity and improvement of the ChefsClub platform, I also seek to ensure that the deliverablesoccur with quality, are testable from conception, with the necessary scalability andaccording to the company's strategic interests.- Monitoring and optimizing platform performance (Web, APIs, Android, and iOS)(Newrelic, Rapid7, Firebase Performance).- Leadership of projects with external customers (Apoie um Restaurante, This is Living).- Technology budget management (People, Tools, and Services) - 42% reduction in Technology, Product and BI costs (Heroku, AWS, Mailchimp, Tools, etc.).- Project management using agile methods (Scrum) and the Kanban Method.

Rio De Janeiro Area, Brazil

- Leadership of Mobile and Frontend development teams.- Development and maintenance of Android and iOS applications.- Responsible for defining and implementing QA processes.- Review of Analytics solutions (Mixpanel, Firebase) and implementation of A/B Testing culture through Remote Config.- Review of user experience (Check-in, Reservations) on mobile apps.- Definition of architecture and launch of the new website ChefsClub.com.br

Rio De Janeiro Area, Brazil

Mobile (iOS, Android, Xamarin) development and maintenance tasks but mainly focused in Android platform, being responsible for developing the new Android application using MVP architecture, RxJava2, RxLocation and RxBindings reactive libraries, Fresco, Realm, Butterknife and Dagger 2. Usage of Fabric platform in order to support the QA process and beta testers users.Development of API endpoints and refactoring activities considering best software engineering practices in Rails web applicationsTechnical and Agile mentoring both Technology and Product teams.

Rio De Janeiro Area, Brazil

Overview:- Delivered robust and scalable solutions across multiple technologies and platforms.- Led Android app development for LatAm.Key Responsibilities:- Frontend, Backend, and Mobile software development and architecture activities across various technologies and programming languages.- Fine-tuning: Configured and tuned ActiveMQ (broker and client sides) to optimize message queuing and processing.- Testing: Conducted extensive testing using JMeter, JUnit, Easymock, and DBUnit.- Performance Analysis: Performed performance analysis using APM tools like Newrelic, Yorkit, Splunk, and Logentries.Achievements:- Delivered multiple scalable Dating product features across multiple technologies and platforms for Latin America.- Enhanced tracking conversion capabilities on the Match LatAm blog network.- Successfully developed and published The first generation of Android apps for Match LatAm dating brands.- Successfully developed and published The app "Beija Eu!" - the hot trend from the Brazilian Carnival in 2015.Technologies & Tools:- Java Environment: Spring Tools Suite, JSP, Spring, Spring MVC, XStream, EhCache, ActiveMQ, BigIP, Apache HTTP Server, Tomcat 7, Oracle 11, MySQL 5, Lucene, Solr, Memcached.- .NET Environment: Visual Studio 2013, ASP.NET MVC, .NET 4.5.2, SQL Server 2012, IIS 7.- Payment Gateways: Bibit, Paymentech, Purebros, PayPal, Sitef, and Cielo- Frontend Tools & Libraries: Grunt, Bower, Ember.js, Backbone.js, Handlebars, jQuery.- Android Tools & Libraries: Android Studio, Butterknife, Picasso, EventBus, Retrofit/Retrofit 2, GSON, Realm, Facebook, Fabric.io, various analytics APIs.- Configuration & CI: Subversion, Git, TFS, Jenkins

Rio De Janeiro Area, Brazil

Client: Petrobras (www.petrobras.com.br)Overview:- Led the development of applications using a diverse set of technologies and frameworks. Actively promoted agile practices and methodologies within the development team and served as a speaker at internal technical events.Key Responsibilities:- Developed and maintained applications for different business areas inside Petrobras.- Disseminated agile practices and methodologies such as XP, TDD, BDD, Scrum, and Kanban across development teams.- Delivered presentations and conducted workshops on commonly used frameworks and experimental technologies within the development department.Achievements:- Successfully implemented agile practices, improving team collaboration and project delivery times.- Enhanced the technical proficiency of the development team through regular knowledge-sharing sessions and technical events.- Delivered high-quality software solutions that met stringent company standards.Technologies & Tools:- Frameworks & Libraries: Maven 2, Spring 2.5.x, Flex 3, JSF 1.2, RichFaces, Tomahawk, Mojarra, EhCache, Lucene, Groovy.- Application Servers: Tomcat 6, WebLogic 10.3.- Databases: Oracle 11g.- Testing & CI Tools: JUnit 4, Unitils 3, Spock, Selenium, Geb, Hudson.- IDE & Version Control: IntelliJ IDEA, Subversion.

Rio De Janeiro Area, Brazil

Client: Sprink ( www.sprink.com.br )Overview:- Provided consulting services for application development, focusing on mobile and web solutions. - Leveraged GPRS and 3G technologies expertise to deliver robust and reliable systems across various hardware platforms.Key Responsibilities:- Consulted with clients and end-users to gather and analyze requirements, ensuring solutions met their specific needs and objectives.- Delivered tailored solutions addressing specific client needs.- Conducted regular client and end-user meetings to provide updates, gather feedback, and adjust project scopes as necessary.- Provided expert guidance and recommendations, ensuring alignment with Sprink's business objectives and technical requirements.Achievements:- Developed and delivered a comprehensive mobile, backend, and reporting solution for firefighters conducting field inspections of security equipment, creating a new vertical within the client organization.Technologies & Tools:- Programming Languages: Java, C#.- Frameworks & Platforms: JSE, J2ME, .NET CF 2.0 and 3.5, ASP.NET Webservices.- Databases: SQL Server 2008.- Hardware: Palm SPT 1550, Symbol MC1000, Opticon H19A, ZEBRA RW-420.

Rio De Janeiro Area, Brazil

Client: BrasilCap Capitalizações, Tim BrasilOverview:- Provided consulting services for developing customizations and enhancements in financial software modules and applications.Key Responsibilities:- Developed customizations for CyberFinancials modules from Inffinix Software using JEE, Adobe Flex, Oracle 10g, and Pro*C.- Performed Java development and analysis for the Capitalization segment at BrasilCap Capitalizações using J2EE 1.3, EJB 2.1, JDeveloper, Mantis, and CruiseControl.- Collaborated with in-house and client teams to integrate and deploy customized software solutions.Achievements:- BrasilCap Capitalizações: Successfully launched the Ourocap Fiador product, widely recognized in the real estate rental market.- Tim Brasil: Customized CyberFinancials to meet Tim Brasil's specific needs.Achievements:- BrasilCap Capitalizações: Successfully launched the Ourocap Fiador product, widely recognized in the Brazilian real estate rental market.- Tim Brasil: Successfully customized CyberFinancials for Tim Brasil, enhancing its billing operations workflow.Technologies & Tools:- Programming Languages: Java, Pro*C.- Frameworks & Platforms: JEE, Adobe Flex, J2EE 1.3, EJB 2.1.- Databases: Oracle 10g.- Development Tools & CI: Eclipse, JDeveloper, Mantis, CruiseControl.

Rio De Janeiro Area, Brazil

Overview:- Provided specialized instruction in Java programming language, focusing on preparing students for the SCJP exam and training IT professionals to become proficient Java developers. Key Responsibilities:- Taught Java technology to students, ensuring a thorough understanding of core concepts and practical applications.- Created and updated course materials to support effective learning, including lecture notes, hands-on exercises, and practice exams.- Prepared students for the SCJP exam through targeted instruction, practice tests, and individual mentoring.- Trained IT professionals to become Java developers by covering advanced topics, practical coding exercises, and industry best practices.Technologies & Tools:- Programming Language: Java.

Rio De Janeiro Area, Brazil

Client: Vibra Energia (Oil & Gas)Overview:- Led Java development and analysis projects from the CRM area following the RUP methodology.Key Responsibilities:- Conducted requirements gathering, database modeling, and UML modeling tasks.- Architected, Developed, and deployed Java Web/Enterprise applications guided by Design Patterns and best market practices.- Planned, Created, and executed test plans.Achievements:- Delivered projects for different business areas (Aviation / Gas Station / HR), positively impacting day-to-day activities for thousands of employees.- Facilitate Software Factory communication with clients/stakeholders.Technologies & Tools:- Programming & Frameworks: Java, JEE, EJB 2, JPA, Hibernate, JSF, Struts, JUnit, PLSQL, JavaMail, Apache POI, XDoclet, Apache Tiles.- Tools & Platforms: Ant, Oracle 10g, Rational Rose, Enterprise Architect 7, Eclipse, JBoss, OC4J.- Methodologies: RUP.

Rio De Janeiro, Rio De Janeiro, Brazil

Client: IBGE (Geography and Statistics Brazilian Institute)Overview- Led the analysis and development of the payroll system for the 2007 Demographic Census.Key Responsibilities- Utilized various technologies, including Java Web, J2EE, Struts, Hibernate, JMS, and EJB, to develop and maintain the payroll application.- Conducted requirements analysis and collaborated with cross-functional teams to design scalable and robust software solutions.Achievements:- Successfully implemented and deployed a web-based payroll system that streamlined payroll processing for over 85K+ census workers, paying over 300M BRL in under six months.

Master In Science, Artificial Intelligence, Data Mining, Affective Computing

Bachelor, Information Technology