I’m Felipe Hamasaki, a full stack developer in Brazil. I turn complex intelligence, tracking, and fraud-prevention workflows into clear, dependable products.
Production systems are private. These concise case studies explain the problem, my contribution, and the result without presenting confidential work as a public demo.
Technologies I use in production, grouped by the job they do — without arbitrary percentage bars.
I’m a full stack developer based in São Paulo state. I build and modernise operational software for corporate intelligence and fraud prevention, where reliability matters because people use the product all day.
I started on the frontend and now work across the stack. I like being close to product decisions, making trade-offs explicit, and improving the conventions that help a small team move together.
Before software, I taught English for two years and spent six years in HR. Payroll taught me that some bugs are personal; the classroom taught me to explain complicated things without hiding behind jargon.
Building intelligence and fraud-prevention products used around the clock by approximately 100 analysts.
Built and maintained a private package of approximately 50 React components and introduced conventions adopted by a five-developer team.
Built responsive operator interfaces with React, TypeScript, and Tailwind CSS.
Ran payroll, time-and-attendance systems, onboarding, offboarding, and management reporting for an American manufacturer.
Supported personnel administration and built reporting and data cross-referencing in Excel.
Taught beginner-to-intermediate English for two years.