William Sumida Email & Phone Number

São Paulo, Brazil

• As a tech lead, my role is to guide developers with implementations and code reviews, dene the software architecture, and communicate with stakeholders to ensure the best business solution with the highest technical delivery quality (always highlighting trade-offs). Additionally, I occasionally assist other company projects through mentoring.• Administrative system for a Mobile App: Currently developing a content management system for a mobile application as well as theapp's own backend. The challenge of the project is ensuring performance during peak times, which has a trafc of 10 millions requests per month. To overcome this challenge, we are using Kubernetes to ensure redundancy and scalability (creating new pods on demand). We implemented a caching layer with Redis, we constantly optimize database queries, and use a monitoring system alongside stress tests to nevaluate latency, p99, throughput and overall system stability under high load conditions. Main technologies/skills used in the project:NestJS, Domain Driven Design, Event Driven Architecture, Redis Cache, Microsoft Azure, React, PostgreSQL, KeyVault, Unit testing (Vitest), BullMQ, Typescript, CI/CD, Apache Kafka.

São Paulo, Brazil

• Infrastructure improvement: Implemented Continuous Integration/Deployment Pipeline Integration using Gitlab which improved our software quality and delivery speed. Created a PostgreSQL cluster to improve query response times by distributing the load across multiple machines and ensuring no data is lost. We used a load balancer with round-robin strategy for applications with duplicate instances runningin Docker.• Data pipelines (ETL): Developed an ETL from scratch using Python, Geopandas and PostGIS. It loaded data to a PostGIS database from SFTP repositories and MinIO. The data pipeline was later upgraded using Apache Airow with custom developed RabbitMQ sensors which triggers a job coming from a queue.

São Paulo, Brazil

• Rewrite of a legacy system: Improved the accuracy of address search along with technology coverage layers (copper, ber optics, 4G, 5G, etc.). I adopted a microservices architecture to ensure scalability and enable the commercialization of the developed APIs. The APIs were developed using Express, and the frontend—where only the map technology and API integrations were modied—was built with Vanilla JSusing Node.js and the coverage layers were served with PostGIS and Geoserver.

Londrina - Pr

We founded FItovision in June 2016 to improve the productivity of agriculture researchers by collecting data, running statistical analysis and creating reports required by the brazilian government (MAPA).By the end of 2022 I had the following achievements:- Got approval to participate in the Intuel incubation program.- Pitched our project to investors in startup events and presented our service to future clients.- Built a backend service to interpret statistical data (scott-knott, duncan, tukey) and write reports following scientific paper specifications (Abstract, materials and methods, results, discussions and conclusion).- Built a offline first mobile app using React Native to collect data from experiments. It was able to collect data without internet connection and sync with a Node.js backend whenever the user had access to internet.- Worked on a machine learning project to evaluate soybean images captured by drones. Classification and regression models were used to identify the percentage of asian soybean rust present.- Configured the infrastructure with Amazon EC2 for applications and databases, Route53 to configure the domain and S3 for storing files. Both frontend and backend were served with NGINX.