I like understanding how things work on both sides of the application. I might be refining a React interface one moment and modeling a business rule or backend integration the next.
I've spent more than three years building for the web. In that time I've worked with React, Node.js, TypeScript and SQL on applications that had to work for real: authentication, third-party integrations, REST APIs and responsive interfaces that stand up to actual use.
I've shipped event management systems, payment gateways, reservation flows, registration and check-in. I've learned that the hard part is almost never writing the code - it's understanding the problem well enough not to write too much of it.
I started in support and infrastructure, and I think that left a mark: I like knowing what sits under the abstraction. Today I'm studying Software Engineering and pulling that thread toward architecture, backend and systems closer to the hardware.
Studying now
Summary
I also work with
And the topics behind them
Quaestum Consultoria Empresarial
Building and maintaining full stack web applications, from the interface to business rules and third-party integrations.
Fale Alto
Building responsive sites and landing pages, from gathering requirements with the client through delivery and maintenance.
CERO Imagem Digital
First professional contact with technology: support, infrastructure and the curiosity to automate whatever could be automated.
From bank slip to payment receipt, without leaving the browser.
Drop the PDF of a payment slip, the app pulls out amount, date, payer and authentication code, and lays out an A4 receipt ready for a Gov.br digital signature. Parsing with pdf.js and PDF generation run on the client: no document or amount ever touches a server.
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An API foundation meant to grow without turning into a mess: separated layers, edge validation, structured logs and errors that say what happened.
A lean interface for project progress: clear states, high information density and no decoration that gets in the way of reading.
A PWA study that validates credentials via QR Code without a network, stores records locally and syncs as soon as connectivity returns.
More projects on GitHub@dollyzn
A lot of the complexity we write exists because we skip this step. I ask more up front so I rewrite less later.
The commit is the beginning of the code's life, not the end. I write for whoever opens that file in six months - usually me.
Clear contracts, errors that explain what happened and predictable states. That's what separates a system that works from one that only works on the happy path.
Universidade Cruzeiro do Sul
2025 - 2029
In progress
Instituto Federal Fluminense
2021 - 2023
Completed
I read docs, articles and code in English every day - that's where the information arrives first.