William Hanemann da Silva, Developer in Ribeirão Pires - State of São Paulo, Brazil
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William Hanemann da Silva

Verified Expert  in Engineering

Full-stack Developer

Ribeirão Pires - State of São Paulo, Brazil
Toptal Member Since
September 20, 2022

William is a web application developer fascinated by networks and security who has spent the last ten years developing various websites and applications. Over the past five years, he has used Vue for projects in industries including business management, medicine, public transportation, and clothing design. William takes pride in his job, and values work dedication.


Dr. Pediatra & Cia
JavaScript, HTML, CSS3, Node.js, Cloud Firestore, CouchDB, PouchDB...
Viação Talismã
JavaScript, CSS3, HTML, Vue, Progressive Web Applications (PWA), Linux...




Preferred Environment

Linux, Windows, Google Chrome, Visual Studio Code (VS Code), Node.js, JavaScript, CSS3, HTML, Vue, HTML5

The most amazing...

...thing I've built is a clinic management app that increased the attendance threshold by 300% and reduced the time spent on monthly health plan billing by 91.6%.

Work Experience

Full-stack Engineer

2017 - 2021
Dr. Pediatra & Cia
  • Designed and developed a clinic management application used by all clinic branches for thousands of patients, leading to a 300% attendance threshold increase and 91.6% less time spent on monthly health plan billing.
  • Created the company website, initially providing clients with basic information about viable medical insurance, available services, clinic employees, and locations.
  • Built and designed a public progressive web application used by patients to schedule and manage their medical appointments by themselves.
  • Collaborated on decision-making and worked closely with company partners as an IT consultant.
Technologies: JavaScript, HTML, CSS3, Node.js, Cloud Firestore, CouchDB, PouchDB, Progressive Web Applications (PWA), Express.js, Vuetify, NW.js, Linux, Visual Studio Code (VS Code), Computer Networking, Vue, HTML5, User Interface (UI), Front-end, User Experience (UX), Web Development, Web App Development, Full-stack, Full-stack Development, Firebase, Chart.js, Front-end Development, REST APIs, Data Visualization, Design, Deployment, Management, PDF.js, Twilio API, XML, Hash, Realtime, Offline Data Synchronization, Data Synchronization, User Management, Database Modeling, Google Material Design, Scheduling, Development, Architecture, OAuth 2, APIs, CSS, Firebase Hosting

Web Developer and Designer

2016 - 2019
Viação Talismã
  • Designed, developed, and maintained the company website.
  • Enabled students and teachers to apply for the free school bus pass online.
  • Developed a dynamic bus schedule, allowing city residents to access bus routes and locations.
Technologies: JavaScript, CSS3, HTML, Vue, Progressive Web Applications (PWA), Linux, Visual Studio Code (VS Code), HTML5, User Interface (UI), User Experience (UX), Web Development, Mobile-first Design, Design, Deployment, Management, Database Modeling, Scheduling, Development, Architecture, CSS

Clinic Management System

I architected, modeled, designed, developed, deployed, and managed a complete clinical management software system utilized in the care of thousands of patients across various industries. The application featured a real-time distributed database, ensuring synchronization across all company branches. It also automated local and remote backups regularly. Even in the event of an internet connection drop, the system continued to function seamlessly and would sync all data once the connection was restored.

The application included:
• Comprehensive appointment management with WhatsApp reminders.
• Creation of prescriptions, exam requests, and certificates.
• Patient management, including medical history and growth development with charts for data visualization. The US CDC provided all reference data.
• User management with role-based permissions and authentication for doctors, employees, and patients.
• Consultation tables with an extensive drug list provided by the national drug agency.
• A comprehensive ICD reference.
• Full support for generating health plan billing in compliance with national government health agency regulations, including creating statistics, reports, and XML files for communication between relevant parties.

Parking Lot Manager App

Created an Android application using Vue, Quasar, and Capacitor to manage the parking of cars, motorcycles, and trucks on a parking lot. Cars and motorcycles would stay parked between a few hours and a few days, while trucks were parked for weeks or over a month and were charged based on the number of axles.

Because some vehicles were charged based on the number of parked minutes rather than hours, there were many possible pricing solutions. The most challenging part of the project was creating a simple and easy-to-use interface to create and manage the parking prices and maintain the automated list of the available parking spots for every vehicle type.

The application calculated the parking price for every vehicle based on additional factors, such as the time of day and existing parking subscriptions. When entering the parking lot, the drivers were given receipts with QR codes that they would scan when leaving to generate invoices.

Inventory Manager for Local Tailors and Dressmakers

Volunteered on an application development project to keep an inventory of fabrics and patches in available sizes, colors, types, and quantities, with the app able to compare, combine, and track available materials. Users could upload unlimited photos for each record and comment, describe the fabric, and add keywords and favorites.

The record included all known fabric types within the app's internal database. It used color palettes and studies extracted from uploaded photos to help users choose threads, buttons, and accessories that work well with their material.

The app organized new ideas, pictures, and documents in filtered and classified galleries, giving users a place to keep their inspiration photos and notes while also being able to attach images and PDFs. Everything was searchable by keywords, colors, fabric names, titles, and descriptions. Users could create patterns based on geometric shapes, following the quilt-sewing technique, and obtain information on what they need to work on their project based on the available inventory.

Cryptocurrency Dashboard

A fully customizable desktop dashboard designed to follow cryptocurrency prices and transactions, offering support feedback lacking from exchange platforms, like the possibility to check prices by considering trading fees.
The best matching pair for a selected currency is suggested, aiming for the highest possible profit and the owned assets that could bring more profits upon selling, with or without considering the owned amount. All data is fetched in real-time through exchange platforms' APIs, and as a privacy protection measure, all user data and calculations are kept and processed on the user's device. As expected, the application has scrolling price ticks, multiple charts and views for each trading pair (including floating cards and ticks), price alerts, calculators, and more. Its financial calculator allows the user to quickly check possible transaction profit and losses considering the fees, which substantially supports trade analysis.

Clothing Store | eCommerce

An online store created with Nuxt.js and Strapi aimed at selling children's and adult (women's) clothing. It had integration with the local postage system for freight calculation and with payment API (Mercado Pago).

Emergency Care BMI and Age Calculator

A clean BMI and age calculator used during medical care in emergency care units. The requirements were simple:

• Doctors needed fast and instant access to inputs upon launching the app.
• All content should be available on the initial screen, with no page changing or scrolling.
• Input data should be masked, validated, and auto-corrected so that doctors should not worry about manual corrections or measurement units (weight, height, and dates). Results were always consistent.
• Charts show the current person's indexes according to data provided by the US CDC.

Although initially requested by a doctor, four years later, the entire team still uses the application today.
2016 - 2019

Associate's Degree in Information Security

FATEC - São Paulo, Brazil


Vue, Vue 2, Vue 3, REST APIs, Node.js, NW.js, Chart.js, Twilio API


Figma, Mongoose, Capacitor


Vuetify, Quasar, Nuxt.js, Jest, OAuth 2, Realtime, Express.js, Electron


Linux, Windows, Google Chrome, Visual Studio Code (VS Code), Firebase, PDF.js, Android, iOS


JavaScript, CSS3, HTML, CSS, HTML5, Sass, TypeScript, SCSS, Python 3, C#, XML


CouchDB, PouchDB, Database Modeling, Data Synchronization, Cloud Firestore, MongoDB




Operating Systems, Progressive Web Applications (PWA), APIs, User Interface (UI), Front-end, Web Development, Web App Development, Full-stack, Full-stack Development, Front-end Development, Mobile-first Design, Architecture, Development, Deployment, Computer Networking, Cryptography, Firewalls, Firebase Hosting, User Experience (UX), Vitest, Design, Data Visualization, Offline Data Synchronization, User Management, Google Material Design, Scheduling, Security, Vite, Content Management Systems (CMS), Payment APIs, Online Payments, Strapi, Hash

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