David Barbosa Moseler
Verified Expert in Engineering
Software Developer
São Paulo - State of São Paulo, Brazil
Toptal member since August 26, 2020
David is a freelance full-stack software engineer backed by a robust academic background in science, applied mathematics, and statistics. With a combination of technical skills and an understanding of business and product demands, David has made it feasible for startups to launch their business models into successful enterprises. He's also helped more mature companies solve deep architectural and business modeling problems that prevented them from employing resources efficiently.
Portfolio
Experience
- JavaScript - 7 years
- PostgreSQL - 6 years
- Python - 5 years
- Flask - 4 years
- Vue - 3 years
- Ruby on Rails (RoR) - 3 years
- Vuetify - 1 year
- Materialize - 1 year
Availability
Preferred Environment
Tmux, Vim Text Editor, Linux, Python, Flask, APIs
The most amazing...
...project I've done was the platform for the fintech company Solfácil, which helped turn their idea into over $100 million valuation through our partnership.
Work Experience
DevOps Consultant
ZiffDavis
- Helped maintaining legacy systems and designed more modern alternatives.
- Structured data center monitoring strategies and cloud microservice infrastructure.
- Identified company-wide security breaches and countered hacker activity.
Business Partner
Solar499
- Developed a platform for generating partnership proposals for businesses looking for ways to cut expenses or earn additional revenue through solar energy.
- Implemented Python and Flask for the back end, React for the front end, and PostgreSQL for the database.
- Developed a complete cloud infrastructure locally for an easily testable and deployable micro-service architecture using Docker and Kubernetes.
Technical Co-founder (CTO)
Crédito Samba
- Developed a platform for integrating with eCommerce or physical retail and providing consumer credit.
- Wrote it with PHP and Symfony on the back end, and React (previously AngularJS) on the front end.
- Worked on email and process automation to cut early expenses.
Co-founder
Solfácil
- Developed, from scratch, a production-level application that drives the fintech, solar-panel funding startup, Solfácil. Worked from the database back end to the CSS front end after consolidating my knowledge and filling gaps.
- Hired and led a team for further development and maintenance of the platform.
- Increased my understanding of web frameworks, ecosystems, and tools in Python and used that on later projects.
- Adopted modern front-end frameworks and technologies after a comprehensive study of JavaScript, Vue.js, and Webpack.
- Evolved my knowledge of cloud services and DevOps further and was responsible for the deployment, namespace, DNS, and more.
- Worked with Heroku and file storage at Firebase and AWS S3 with proper security and permissions via pre-signed URLs.
- Adopted proper database querying practices with low-level SQLAlchemy expression language when needed.
- Created advanced form and data-table tools with advanced filtering, pagination, validation, and search, for customizable fields and items.
- Automated REST API creation from business rules through data mappings and functional programming.
- Gained practical and comprehensive experience with front-end design, HTML, CSS, and Materialize.
Software Developer
Garagem Startup Studio
- Built this platform alone and from scratch (contract) and developed an industrial fintech application directed toward retail credit.
- Became familiar with Rails and other full-stack web frameworks and fully adopted test-driven development through RSpec.
- Modeled credit policies through a self-conceived tool to convert policy fluxograms into executable graphs or state machines, which are very similar to today's successful tools in that industry, such as Nogord.io.
- Wrote custom production deployment into AWS EC2 via Capistrano.
Software Developer
Studiare
- Obtained proficiency in Ruby on Rails and general concepts of higher-level languages, web frameworks, and the ecosystem.
- Started as a junior developer and was quickly promoted. Started leading the team in a moment of necessity, learned quickly, dealt with high responsibility, and became pragmatic and effective in development and decision-making.
- Delved deep into best practices in object-oriented programming and proper modeling of the business domain as a way to solve problems that were seen as insurmountable, reduce the bug count, and turn system chaos into deterministic behavior.
- Handled the deployment to Heroku and managed cloud plugins for logging, application monitoring, and more.
Software Development Intern
Telcomanager Technologies
- Worked in an internship and contributed to the development of complex, low-level, real-time systems for network data collection and consolidation in C.
- Learned the fundamentals of computing science, compilers, operating systems, and networking.
- Gained my first contact with source control, mastery of Unix environments, shell scripting, Regex, and Vim.
- Worked on projects involving JavaScript, HTML, CSS, and other front-end technologies.
Experience
Fintech Application for Solfácil
Toptal React Academy
Education
Master of Science Degree in Computation and Applied Mathematics
Institute of Pure and Applied Mathematics - Rio de Janeiro, Brazil
Bachelor of Science Degree in Theoretical and Mathematical Physics
Federal University of Rio de Janeiro - Rio de Janeiro, Brazil
Certifications
Toptal React Academy Graduate
Toptal, LLC
Deep Learning Nanodegree
Udacity
Data Science Nanodegree
Udacity
Skills
Libraries/APIs
Pandas, NumPy, Vue, REST APIs, React, SQLAlchemy, Scikit-learn, PyTorch
Tools
Git, Vim Text Editor, Tmux, RSpec, Capistrano, Webpack, Docker Compose, RabbitMQ
Languages
Python, JavaScript, TypeScript, CSS, SQL, Ruby, PHP, C#, HTML, C
Frameworks
Flask, Ruby on Rails (RoR), Vuetify, Materialize, Symfony, AngularJS, Ruby on Rails 6
Paradigms
REST, Microservices
Platforms
Docker, Kubernetes, Jupyter Notebook, Heroku, Linux, Amazon Web Services (AWS), Unix, Amazon EC2, Firebase, AWS Lambda, Apache Kafka
Storage
PostgreSQL, Amazon S3 (AWS S3), Microsoft SQL Server, MongoDB, Riak, Datadog
Other
Data Science, Machine Learning, Deep Learning, Neural Networks, APIs, API Design, Data Scraping, Web Scraping, GitFlow, DOM, Architecture, Scientific Reasoning, Scientific Method, Research & Critical Thinking, Experimental Design, Statistics, Linear Algebra, Probability Theory, Microeconomics, Finance, Portfolio Management, Fintech, Startups, ECS
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