Fabricio is currently unavailable
Fabricio Demattê
Verified Expert in Engineering
Software Engineer and Developer
São Paulo - State of São Paulo, Brazil
Toptal member since June 27, 2024
Bio
Fabricio is a software engineer passionate about open source and crafting performant, maintainable code. He has extensive experience building robust back-end systems and comprehensive ETL pipelines using Rust, JavaScript, Python, and SQL. He took part in industry-leading products for the advertising business with ShowSeeker Pilot and in the security and ID authentication industry with IDVerse. He is most notable for bringing performance and scalability that moved millions of dollars in revenue.
Portfolio
Uber
Amazon Web Services (AWS), Go, SQL, TypeScript, React
Nubank
Clojure, ClojureScript, Amazon DynamoDB, Amazon Web Services (AWS), Java, Scala
IDVerse
Rust, Python, Amazon DynamoDB, Amazon Kinesis Data Firehose...
Experience
- TypeScript - 5 years
- Python - 5 years
- Linux - 5 years
- React - 5 years
- PostgreSQL - 5 years
- Distributed Systems - 4 years
- Rust - 4 years
- Serverless - 3 years
Preferred Environment
Linux, Jira, Amazon Web Services (AWS), Rust
The most amazing...
...project I've designed: a business metrics platform for IDVerse that integrates the products transactional data into a centralized data lake, enabling a BI team.
Work Experience
Software Engineer
2025 - PRESENT
Uber
- Partnered with product, data-science, and SRE teams to design and launch rider- and driver-facing Uber Eats features worldwide, translating complex data insights into seamless in-app experiences.
- Ran the growth experimentation pipeline end-to-end. Formulated hypotheses and designed A/B and multi-armed-bandit tests with Uber’s Experimentation Platform.
- Iterated on new ideas to attract drivers to Uber Eats.
Technologies: Amazon Web Services (AWS), Go, SQL, TypeScript, React
Software Engineer
2024 - 2025
Nubank
- Streamlined identity verification, contributing to the identity fraud/challenge team managing the challenge flow and incremental rollout of security features. This ensured scalability and security for over 5 million daily authentication requests.
- Conducted OCP tests to prove and ensure stakeholders' reliability.
- Fixed critical vulnerabilities in the liveness authentication flow that allowed scammers to bypass identity validation and impersonate users.
Technologies: Clojure, ClojureScript, Amazon DynamoDB, Amazon Web Services (AWS), Java, Scala
Senior Software Engineer
2022 - 2025
IDVerse
- Developed and optimized the face access project, a zero-knowledge biometric authentication tool, reducing operational costs by 40% and saving up to $500,000 in fraud prevention for multiple clients.
- Designed and developed the company's business metrics platform, a comprehensive ETL pipeline that integrates data from multiple company products into a centralized data lake, enhancing data transformation, storage, and analytics capabilities.
- Implemented the FeatID engine, converting face images into searchable float arrays, optimizing security protocols, and handling large-scale data and identity hashes.
- Led the port of our facial recognition engine from C++ to Rust using OpenCV and OpenVINO, enhancing processing speed and memory safety by leveraging modern APIs of image processing and inference, which led to more efficient and reliable AI workloads.
Technologies: Rust, Python, Amazon DynamoDB, Amazon Kinesis Data Firehose, Amazon Simple Queue Service (SQS), Amazon Redshift, Amazon Web Services (AWS), Serverless, Optical Character Recognition (OCR), Databases, Jira
Back-end Software Engineer
2021 - 2022
ShowSeeker
- Leveraged monitoring tools to identify hotspots and implement a cache-aside strategy that improved performance by 150%, measured with an integration testing pipeline.
- Developed a database migration pipeline from MySQL to PostgreSQL to use incremental materialized views, improving the performance of complex queries by 150%.
- Implemented change data capture for the PostgreSQL database to improve the ETL pipeline and built an incremental cache that reduced database load, improving performance by 200%.
- Built an in-house library to static-check code, improving the developer experience and reducing bugs by 20%.
Technologies: Rust, JavaScript, PostgreSQL, MySQL, Python, Prometheus, Grafana, Redis, Amazon Web Services (AWS), Databases, Jira
Full-stack Software Engineer
2020 - 2021
NTT Data
- Created an embeddable chatbot application from scratch for Unilever partners' eCommerce, totaling up to 1 million daily users.
- Introduced a product recommendation feature to the conversation flow, leading to a 10% increase in traffic and conversion rate. I leveraged webhooks in Node.js and Azure Functions.
- Designed and documented a user-facing API for customers to integrate our embeddable chatbot bundle into their websites.
- Led entry-level developers regarding code quality, testing, and best practices in the React/Node.js ecosystem.
Technologies: JavaScript, Node.js, React, Java, Web Development, TypeScript
Full-stack Software Engineer
2019 - 2020
Vega I.T
- Built the company's smart locker admin platform to integrate the hotel management system. Today, the platform is used by more than 1,500 hotels worldwide.
- Coordinated with cross-functional teams to achieve design requirements.
- Guided entry-level developers on code quality, testing, and best practices in the React/Node.js ecosystem.
Technologies: JavaScript, Node.js, Next.js, React, Web Development, Jira, TypeScript
Web Developer
2018 - 2020
Workana
- Built a web application that leveraged OCR software to read brokerage receipt notes and provide tax insights.
- Developed a geolocation-based search feature on Selfit's Angular web page, significantly enhancing user experience and increasing customer conversion rates for one of Brazil's leading gym chains.
- Performed full-stack development tasks for a condominium management web application, introducing advanced financial and security features to streamline operations and enhance user safety.
Technologies: JavaScript, Node.js, React, Python, Angular, Optical Character Recognition (OCR), Web Development, TypeScript
Experience
GNU "rm" Command with Extra Features
https://github.com/demfabris/rmxThis project involved building a close port of the GNU "rm" (remove) command in Rust. This improved performance and added extra features, including concurrent unlink, system trash bin integration, and unrecoverable data wiping.
Gistit, Peer-to-peer Code Sharing
https://github.com/demfabris/gistitCreated a command-line interface (CLI) application in Rust that leverages centralized and decentralized technologies to share code snippets with peers. The application was a success and accumulated over 50,000 unique users. In addition, I developed a multiplatform daemon that establishes a connection to the InterPlanetary File System (IPFS) network.
Open-source Contributions
https://github.com/demfabris• libp2p: Implemented CLI tooling to generate key material for new peer connections to improve the development experience.
• surrealdb: Improved inner libraries (storekey, surrealdb-derive) to perform zero-copy deserialization.
• dotenv-linter: Refactored the core code to improve linting performance and overall runtime.
• lsd: Introduced custom config file feature augmenting customization capabilities.
• expo: Fixed an inconsistency between Android and iOS platforms in the expo-calendar module.
• surrealdb: Improved inner libraries (storekey, surrealdb-derive) to perform zero-copy deserialization.
• dotenv-linter: Refactored the core code to improve linting performance and overall runtime.
• lsd: Introduced custom config file feature augmenting customization capabilities.
• expo: Fixed an inconsistency between Android and iOS platforms in the expo-calendar module.
Management App for Psychologists
https://psicopilot.comThe project is a SaaS mobile app designed to streamline and solve multiple pain points of psychology professionals in Brazil by implementing patient auto-scheduling, WhatsApp integration, GMeet and GCal integration, and much more. The Expo/React Native app is currently being tested internally via TestFlight.
Education
2015 - 2019
Bachelor's Degree in Statistics and Data Science
University of Sao Paulo - Sao Paulo, Brazil
Skills
Libraries/APIs
Node.js, React
Tools
Amazon Kinesis Data Firehose, Amazon Simple Queue Service (SQS), Grafana, Jira, Expo
Languages
Rust, Python, JavaScript, TypeScript, Java, Clojure, Scala, C++, Go, SQL
Frameworks
Next.js, React Native, Angular, ClojureScript
Platforms
Linux, Amazon Web Services (AWS)
Storage
PostgreSQL, Databases, Amazon DynamoDB, MySQL, Redis
Other
Web Development, Distributed Systems, Computer Science, Back-end, Amazon Redshift, Prometheus, Serverless, Data Science, Optical Character Recognition (OCR), Networking, Supabase
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.
Top talent is in high demand.
Start hiring