Available for new projects
I build every layer of web systems, SaaS products, Flutter apps and desktop POS software on my own: interface, API, database and deployment. Today that means 4 products live and 4 projects delivered to clients.
VendaíLive
Open the Vendaí projectWhat I built for Vendaí
Offline-first POS ecosystem for small businesses. View the project · Vendaí
Work
Systems, products and interfaces built with attention to detail and a focus on results.
Video previewA complete point-of-sale system for pet shops, feed stores, grocery stores, and neighborhood shops: POS with barcode scanner, cash register, inventory, customer tabs (fiado), accounts payable, PIX (Brazil's instant payment system), 50+ reports, and Secure Receiving — all working without internet, with cloud sync and a mobile management app.
Video previewB2B store for mobile phone accessories: a catalog of 349 products with filtering by device (293 models), progressive pricing by quantity, a cart with color selection, real shipping rates, and a checkout that opens WhatsApp with the order ready to send. Full admin panel for the store owner, Excel/PDF export, and Meta Pixel + Conversions API tracking.
Video previewA complete management system for pet shops: a schedule with real-time status via Socket.io, clients, pets, finances, team members, and monthly/annual subscriptions via Stripe — an installable PWA for phone or computer.
Video previewA complete CRM for Brazilian sales teams: 9-stage pipeline, drag-and-drop kanban, integrated WhatsApp Cloud API, custom fields, funnel reports, sales goals, and an installable desktop app — 4 repositories, one product.
Video previewTwo-sided app for used cooking oil collection: the generator (restaurant, condo, school, household) requests a pickup, collectors send proposals, the platform fee is paid via Pix (Brazil's instant payment system), and in the end the app itself issues the disposal certificate.
Video previewTwo products in one: a static QR Code generator with 17 types that runs entirely in the browser, with no sign-up, and a dynamic QR SaaS built on NestJS where the destination of a printed code can be changed at any time, with scans, campaigns, webhooks, and an API.
Video previewCorporate website for Mais Clean Higienização: 9 routes prerendered at build time, a dedicated page for each service with its own metadata and Schema.org, 8 process videos loaded on demand, an installable PWA and analytics with GA4, Microsoft Clarity and Google Ads.
Four kinds of project. Next to each one, a screen from a project of mine that is running right now.
The system your team opens in the morning and closes at night: scheduling, clients, finances, permissions, and subscription billing.
Petzaraview projectReal-time scheduling and active Stripe subscriptions
A company website or landing page built to be found on Google and end in a WhatsApp conversation.
Mais Cleanview project9 indexable pages, 6 services each with its own page and FAQ
Flutter for Android and iOS; Electron for the checkout counter computer. They work without internet and sync when it comes back.
Vendaíview projectLive for macOS, Windows, and Android, with automatic updates
Catalog, cart, and orders connected to what the business already uses: shipping, Pix (Brazil's instant payment system), WhatsApp, and advertising tools.
EA Centralview project349 products and 293 models registered by the client themselvesFive steps, told through what happened at EA Central: from a PDF catalog to orders arriving in the dashboard.
EA CentralOrders dashboard
I talk to the people who will use it and see how the work gets done today. The scope comes from that, not from a list of screens.
At EA Central: The wholesaler sold from a PDF catalog and a WhatsApp list. Customers sent orders as voice messages and the salesperson worked out the discount tier by hand.
Before building the database and server, a clickable version shows the flow and wording to the people who will use it.
At EA Central: The project started from a single-page HTML prototype, which I rebuilt as a full-stack application.
I model the database and the rules in the API; the screens arrive in parts you can use and test.
At EA Central: Storefront, dashboard and API were delivered as three parts. The quantity price table lives on the server, and every order is recalculated before it becomes a message.
Domain, deployment and analytics set up by me, so we know from day one whether the project is being used.
At EA Central: Storefront on Vercel, API and database on Railway, Meta Pixel and Conversions API tracking orders.
After launch, adjustments come from what the client and the users ask for.
At EA Central: The dashboard gained bulk actions so the client could finish setting up 349 products without opening 349 forms.
29 technologies, each running in at least one of the 9 projects that are live or delivered to clients. The icons show where.
Filter by project
Web, mobile and desktop
APIs and business rules
Where the information lives
Where it runs and how it's monitored
Payments, messaging and analytics
This site, too: Next.js 16, React 19 and Tailwind CSS v4.
Reviews and recommendations
Client reviews on Google and public recommendations received on LinkedIn, unedited.Recommendations and reviews are shown in their original language (Portuguese).
Atencioso e prestativo! Trabalho bem feito.
Ótimo profissional.
Ótimo criador de site e programador! bem atencioso e profissional, recomendo 🤝
Profissional que super recomendo para fazer site para sua empresa e desenvolve sistema muito top. Obrigado Lucas.
Google reviews, in the relevance order set by Google (up to 5). Source: Google Maps.
Tenho o prazer de recomendar o Lucas Batista como desenvolvedor. Tive a oportunidade de acompanhar de perto seu trabalho e posso afirmar com tranquilidade: ele é o tipo de profissional que entrega mais do que o esperado.
Lucas tem uma capacidade rara de transformar ideias complexas em soluções claras e funcionais. Seu domínio em tecnologias web modernas (especialmente React e Node.js) é notável, mas o que realmente se destaca é sua capacidade de aprender rápido, refatorar com inteligência e manter o código limpo e sustentável — sempre pensando na experiência final do usuário e na escalabilidade do sistema.
Além do lado técnico, o Lucas é um colega colaborativo, que sabe ouvir, propor e resolver. Ele tem uma postura madura frente a desafios e uma mentalidade de crescimento que o impulsiona constantemente a ir além.
Se você procura alguém que una competência técnica, visão de produto e espírito de equipe, o Lucas é, sem dúvida, uma excelente escolha.
Durante os três anos em que esteve na nossa instituição, nunca vi tamanho comprometimento & responsabilidade com a tecnologia como o demonstrado pelo Lucas.
Ele não apenas se destacou pela sua afinidade com tecnologia, mas também pelo seu empenho em dominar novos desafios e soluções inovadoras, sempre buscando novas tecnologias e habilidades.
Lucas é um profissional excepcional, cuja dedicação são inspiradoras para todos ao redor de nossa equipe, e recomendo ele para qualquer equipe que deseje um profissional qualificado e dedicado para entregar as melhores soluções do mercado.
Choices that repeat across my code, shown in the part of the screen where each one happens.
The browser displays; the API decides price, discount and minimum order. At EA Central, every order is recalculated from the database before it becomes a WhatsApp message.
View the EA Central project
At the counter, a sale can't wait for the connection. Vendaí runs 100% offline; changes go into a queue and sync on their own when the internet comes back.
View the Vendaí project
Barcode scanner and F2–F9 keyboard shortcuts in the Vendaí POS; three steps to book in Petzara. Whoever is serving a customer doesn't hunt for buttons.
View the Vendaí project
EA Central's prices, tiers, brands, models, banners and shipping are edited in the dashboard, with no deployment. The 293 device models were entered by the client.
View the EA Central projectWhere I work today, where I've been and where I studied.
Current
CupCakeLabs Tecnologia
Oct 2026 – present · 1 mo
Software development company: custom systems for clients and our own products.
Experience
Beyond-System · Freelance
Aug 2024 – Apr 2026 · 1 yr 9 mos
Development of web and mobile applications for Beyond-System's clients, with Flutter on mobile and React on the web.
Education
Etec Adolpho Berezin
Feb 2022 – Dec 2024
High school with a technical degree · Mongaguá, SP
6 courses and certificates, including React from Zero to Mastery (Hora de Codar), AWS Educate Introduction to Cloud 101 (Amazon Web Services), Microsoft Certified: Azure AI Fundamentals (Microsoft). See all
A system, a SaaS product, a landing page or an app — let's talk about turning your idea into a well-built digital experience.