Front-end & web developer · Brazil · EN / PT / ES

Web apps and websites that are fast, tested and ready to ship.

I build React + TypeScript web apps (dashboards, e-commerce, booking systems) and fast marketing sites for small businesses. Every project comes with clean code, automated tests, documentation and a live preview link before final delivery.

ReactTypeScriptViteTailwind CSSZustandRechartsVitest + Testing LibraryNetlifyPythoni18n / RTL

Featured web apps

Full applications with routing, state management, validation and test suites. Fictional data.

Pulse Analytics dashboard overview with KPI cards and revenue chart

Pulse Analytics: SaaS dashboard

Auth flow, KPI cards with period deltas, interactive charts, 500-row customer table with search, filters, sorting, pagination and CSV export, validated settings forms, dark/light theme. 29 automated tests.

ReactTypeScriptTanStack TableRechartsZod
Open live app → Maré Coffee store catalog with filters and product cards

Maré Coffee: e-commerce store

Faceted catalog with URL-synced filters, product variants, persistent cart with coupons and free-shipping bar, 3-step checkout with card validation, order history, English/Portuguese with currency formatting. 40 automated tests.

ReactTypeScriptZustandi18nVitest
Open live store → Bookly booking flow with a weekly calendar of available time slots

Bookly: appointment booking system

Client booking flow with real availability (staff hours, breaks, existing bookings, DST-safe), .ics confirmation, reschedule/cancel by code, plus an admin panel with stats, drag-to-reschedule calendar, bookings list and services/team management. 32 automated tests.

ReactTypeScriptdate-fnsZustandVitest
Open live app →

Backend & APIs

Production-style services with auth, validation, tests and docs.

Ledgerly API documentation overview

Ledgerly: multi-tenant invoicing REST API

Node 24 + TypeScript + Fastify + zod + Drizzle. JWT with rotating refresh tokens and reuse detection, owner/member RBAC, strict tenant isolation, invoice status machine with integer-cent math, idempotent payments, rate limiting, RFC 7807 errors, OpenAPI 3.1 generated from code. 33 tests, 95% coverage.

Node.jsTypeScriptFastifyOpenAPIVitest
Open API docs →

AI & automation

Tools that answer customers and remove repetitive work.

Concierge chat widget answering a question on a dental clinic website

Concierge: AI chat widget for any website

One script tag adds a support assistant that answers from the business's own FAQ with cited sources, hands off to a human when unsure, speaks EN/PT/ES and logs unanswered questions. Shadow DOM, 11 KB gzipped, LLM provider via secure server proxy. 33 tests.

TypeScriptBM25 retrievalShadow DOMLLM-readyVitest
Try the live demo → PriceWatch report with biggest price moves chart

PriceWatch: Python price-monitoring automation

Scrapes multiple stores (HTML grids, tables, JSON-LD, pagination) with retries, rate limits and robots.txt checks, stores history in SQLite, detects price/stock changes and generates Excel, CSV and HTML reports. Typer CLI, Docker, CI. 45 tests, mypy strict.

PythonhttpxSQLiteopenpyxlpytest
See sample report → SheetFlow Google Sheets automation kit overview

SheetFlow: Google Sheets + Apps Script automation

Turns a Google Sheet into a back office: lead CRM with enforced pipeline, duplicate detection and business-day follow-ups; invoice PDFs from a Docs template with Gmail drafts; weekly KPI tab with chart; form-intake routing. Typed, tested core logic (21 tests) compiled to Apps Script.

Apps ScriptTypeScriptGoogle SheetsesbuildVitest
See the kit + samples → Clipwise Chrome extension showcase with live in-page demo

Clipwise: Chrome extension (Manifest V3)

Save highlighted text with its source via context menu or shortcut; popup with search and tag/site filters, side panel per site, Markdown/CSV/JSON export and import, offline summaries with optional AI via proxy. Minimal permissions, typed message passing, storage migrations, EN/PT/ES. Try it in the browser without installing. 27 tests.

Chrome MV3TypeScriptService workeri18nVitest
Try the live demo →

Websites for small businesses

Fast, mobile-first sites built to get bookings and messages.

Veterinary clinic website demo

Vet clinic site + 24/7 AI assistant

Online booking, new-client form and an assistant that answers FAQs, flags emergencies and never gives diagnoses.

View demo → Aesthetic clinic website demo

Aesthetic clinic site + AI assistant (PT)

Treatments, prices, GDPR-compliant booking and an assistant in European Portuguese.

View demo → Landing page templates

3 landing page templates

SaaS, dental clinic and app waitlist: responsive, accessible, tested (23 tests), ready to customize.

View templates → Salon website

Salon site + 24/7 AI assistant

Services, prices and a chat assistant that answers clients and sends them to book.

View demo → Clinic landing page

Clinic landing page

Trust signals, services, testimonials and one clear booking call-to-action.

View demo → Restaurant website

Restaurant website (PT)

Menu with prices, reservations and a WhatsApp button.

View demo →

How I work

Clear scope

We agree on pages, features and deadline in writing before I start.

Preview link early

You get a live preview within days, not at the end.

Revisions

I adjust until it matches what you need.

Clean handoff

Source code, README and deployment on your account.

Also

Translation PT ↔ EN

Website and product copy, localization of apps (i18n files).

Automations

Python and Google Apps Script tools that remove repetitive work.

Spreadsheets

Google Sheets and Excel trackers and dashboards.