Marcela is available for hire
Hire MarcelaMarcela Kashiwagi Silveira
Verified Expert in Engineering
Software Developer
San Francisco, CA, United States
Toptal member since June 20, 2012
Bio
Marcela is an experienced web and mobile developer from Brazil currently living in Silicon Valley. She has a very strong understanding of software architecture and also a very strong mathematical background. She was selected by ZDNet as one of ten most influential female tech innovators in Brazil, as well as mentioned on Mashable, Forbes, and others several times.
Portfolio
Calm.com
SwiftUI, Swift, Swift 5, Objective-C, Xcode, Mobile App Design, UIKit...
Toptal Clients
Cocoa Touch, UIKit, OAuth, REST, Core Data, Parse, Firebase, Swift, iOS...
Cabe na Mala
Ruby on Rails (RoR), Ruby
Experience
Availability
Full-time
Preferred Environment
REST APIs, Firebase, Parse, Swift, Objective-C, iOS, Xcode, SwiftUI
The most amazing...
...Thing I’ve built is my own startup, Cabe na Mala, which was acquired in 2016.
Work Experience
Senior Software Engineer, iOS
2021 - PRESENT
Calm.com
- Led different projects and worked in a cross-functional team to brainstorm ideas, build new features, and maintain existing ones.
- Created new experiments using LaunchDarkly and tracked success through Amplitude.
- Used different technologies and proposed ideas to improve code quality and unit tests.
Technologies: SwiftUI, Swift, Swift 5, Objective-C, Xcode, Mobile App Design, UIKit, LaunchDarkly, Amplitude
iOS Software Engineer
2012 - PRESENT
Toptal Clients
- Contributed to the development of iOS projects using Objective-C and Swift.
- Used different APIs and SDKs to create apps from scratch and submit them to the App Store.
- Maintained and added new features to existing apps.
Technologies: Cocoa Touch, UIKit, OAuth, REST, Core Data, Parse, Firebase, Swift, iOS, Objective-C, iOS SDK, Mobile App Design
CTO
2013 - 2016
Cabe na Mala
- Helped create this startup from scratch to exit.
- Managed the technical team, a team of 20+ people based in the US and Brazil.
- Planned, executed, and measured growth strategies, partnerships, and product development.
Technologies: Ruby on Rails (RoR), Ruby
Lead Software Engineer
2011 - 2012
Zign Marketing Digital
- Developed applications and games for the iOS platform using Cocos2D, Box2D and, Chipmunk frameworks, Game Center API, Facebook, Twitter, and LinkedIn Connect.
- Integrated with native web applications using JSON, SOAP, and REST web services.
- Integrated with live TV streaming.
- Developed web applications.
Technologies: LinkedIn API, X (formerly Twitter), Facebook, GameKit, OpenGL ES, Chipmunk, Box2D, Cocos2d, Objective-C
Researcher
2010 - 2011
Signal Processing Laboratory (COPPE/UFRJ)
- Contributed to the NeuralTB project, which produces software supporting the diagnosis of pulmonary tuberculosis through neural networks.
- Developed a solution for checking, transmitting, and synchronizing the databases on mobile devices, in clinics, and in hospitals.
Technologies: Mobile, Databases
Software Engineer
2010 - 2011
UPlay Mobile
- Developed applications and games for iOS using Cocos2D, Box2D, and Chipmunk frameworks, Game Center API, Facebook, and Twitter Connect.
Technologies: X (formerly Twitter) API, Facebook, GameKit, Chipmunk, Box2D, Cocos2d
Software Engineer
2007 - 2010
Stone Age Tech
- Developed and integrated data mining algorithms, including decision trees, linear regression, and logic regression into the company’s applications.
- Developed a CCore database management system with an architecture that ensures high performance even with large volumes of data and compatible with leading market solutions.
- Collaborated with the engineering team for a data mining application in the Object Pascal programming language, including neural network algorithms, genetic algorithms, and automatic extraction of association rules (MBA - Market Basket Analysis).
- Collaborated with the engineering team on an application made in the Object Pascal programming language to create, visualize, and distribute reports used by a number of financial institutions: Itaú, Bradesco, Unibanco, Citibank, Credicard, and BV Financeira.
Technologies: Object Pascal
Experience
WORK DONE
• Within the Consumer Safety team, I worked collaboratively with design, product, and engineering to deliver great user experiences and empower users to define and enforce safety standards for their communities;
• Wrote high-scale reusable code and unit tests to provide a safer and healthier experience to over 400 million active monthly users around the world.
• Implemented analytics to measure performance, use, and success rate of legacy and new features in a complex iOS application using both Objective-C and Swift.
Reddit has reported 430 million active users (2019) and is the third-most downloaded news app in the United States.
• Within the Consumer Safety team, I worked collaboratively with design, product, and engineering to deliver great user experiences and empower users to define and enforce safety standards for their communities;
• Wrote high-scale reusable code and unit tests to provide a safer and healthier experience to over 400 million active monthly users around the world.
• Implemented analytics to measure performance, use, and success rate of legacy and new features in a complex iOS application using both Objective-C and Swift.
Reddit has reported 430 million active users (2019) and is the third-most downloaded news app in the United States.
Calm App
Calm is the #1 app for sleep, meditation and relaxation.
WORK DONE
• Worked as a member of the DTC Growth team and implemented A/B tests to optimize our funnels for user engagement and conversion to premium subscribers, working closely with product and data science to track business metrics and KPIs in order to measure the impact of all experiments I lead or contribute to.
• Led a cross-functional team through multi-sprint projects, scoping, planning, communicating with stakeholders, and driving architectural decisions to build end-to-end features that impact hundreds of millions of users.
• Proposed and executed two large-scale projects that not only improved code quality, testability, and performance, moving from Objective-C and UIKit to SwiftUI and MVVM, but also increased our velocity in conducting A/B tests in the most critical area of our business: the upsell screens for in-app purchases, making new experiments easy, quick to implement, and independent of new app releases via a server-driven UI.
• Implemented our first in-app ML integrated experiment, offering new users a dynamic discount based on their willingness to pay, which resulted in a substantial increase in the number of subscribers and revenue.
WORK DONE
• Worked as a member of the DTC Growth team and implemented A/B tests to optimize our funnels for user engagement and conversion to premium subscribers, working closely with product and data science to track business metrics and KPIs in order to measure the impact of all experiments I lead or contribute to.
• Led a cross-functional team through multi-sprint projects, scoping, planning, communicating with stakeholders, and driving architectural decisions to build end-to-end features that impact hundreds of millions of users.
• Proposed and executed two large-scale projects that not only improved code quality, testability, and performance, moving from Objective-C and UIKit to SwiftUI and MVVM, but also increased our velocity in conducting A/B tests in the most critical area of our business: the upsell screens for in-app purchases, making new experiments easy, quick to implement, and independent of new app releases via a server-driven UI.
• Implemented our first in-app ML integrated experiment, offering new users a dynamic discount based on their willingness to pay, which resulted in a substantial increase in the number of subscribers and revenue.
Education
2011 - 2011
Executive Education Degree in Project Management
Fundacao Getulio Vargas - Brazil
2011 - 2011
Executive Education Degree in Business
Babson College - Massachusetts, US
2006 - 2011
Bachelor’s Degree in Compter Science
Universidade Federal do Rio de Janeiro - UFRJ - Brazil
Skills
Libraries/APIs
REST APIs, Facebook API, OpenGL ES, LinkedIn API, X (formerly Twitter) API
Tools
Xcode, Sublime Text, LaunchDarkly
Languages
Swift 3, Swift, Swift 4, Swift 5, HTML5, Objective-C, HTML, CSS, Swift 2, CSS3, Object Pascal, Ruby, JavaScript, PHP
Paradigms
Object-oriented Programming (OOP), Scrum, REST, Mobile App Design
Platforms
iOS, Google Ads, Mobile, Parse, Parse Server, Firebase, X (formerly Twitter)
Frameworks
UIKit, SwiftUI, iOS SDK, Cocos2d, Box2D, Chipmunk, GameKit, Core Data, Cocoa Touch, Ruby on Rails (RoR)
Storage
MongoDB, MySQL, Databases, PostgreSQL, JSON
Other
Software Development, Facebook, OAuth, Amplitude
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