// Custom software development, on demand. // Web apps, APIs, automations, systems — // built to your specification, delivered // on time. Itapecerica da Serra, SP. // NFS-e on every contract.
Custom software development services for businesses in Itapecerica da Serra and Greater São Paulo — from web applications and APIs to automations, internal systems and complete software projects built under contract.
Full-stack web applications built to specification — from internal management tools and client portals to customer-facing platforms and SaaS products.
REST and GraphQL APIs, third-party integrations, payment gateways, ERP connections and all the backend infrastructure that powers modern software.
Business process automation — eliminating manual work, connecting your systems and building the workflows that save your team hours every week.
Custom internal management systems, dashboards, reporting tools and operational software built for how your business actually works.
Architecture advisory, technical scoping, platform selection and software development consulting — the strategic layer before the first line of code.
Ongoing software maintenance, bug fixing, feature additions and technical support for software systems already in production — keeping your software working.
A registered custom software development limited company in Itapecerica da Serra, São Paulo — building web applications, APIs, automations and systems for businesses across Greater São Paulo and beyond. Formalised, LGPD-compliant, NFS-e on every contract.
Guilherme Samuel Desenvolvimento de Programas Ltda is a registered limited company providing custom software development services, based at Rua Ubatuba, 64, in Vila João Montesano, Itapecerica da Serra, São Paulo. A formalised, LGPD-compliant software Ltda building on-demand software for businesses in Itapecerica da Serra, Greater São Paulo and nationally.
CNPJ 48.279.891/0001-93 — duly registered Ltda
Activity: Desenvolvimento de Programas de Computador Sob Encomenda
Located at Rua Ubatuba, 64, Vila João Montesano — Itapecerica da Serra, SP, CEP 06853-520
NFS-e on all contracts — compliance with SEFAZ-SP and ISS/Prefeitura de Itapecerica da Serra
Client data and software protected under LGPD — Lei 13.709/2018
What a properly formalised software development Ltda delivers — spec-first development, LGPD-compliant engineering, NFS-e documentation and the reliability of a registered company behind every line of code.
We define scope, architecture and deliverables before writing code. No moving goalposts, no scope creep — what we agreed is what we build.
Guilherme Samuel Desenvolvimento de Programas Ltda, CNPJ 48.279.891/0001-93, NFS-e on every contract — a registered company behind every software project.
Software we build follows LGPD principles — data minimisation, security by design, proper consent flows and privacy-first architecture from the start.
Based in Itapecerica da Serra — serving São Paulo, Embu das Artes, Cotia and businesses nationally with custom software development.
NFS-e issued on every contract milestone — SEFAZ-SP compliant. Your procurement team has the documentation they need. No informal arrangements.
Every line of source code delivered to you. No lock-in, no black boxes — you own what we build and can take it anywhere when we're done.
// guilherme_samuel_dev · cnpj 48.279.891/0001-93 · itapecerica_da_serra_sp
"Guilherme Samuel built our internal management system — scoped correctly, delivered on time and exactly to specification. The NFS-e was issued on every milestone, the code was handed over completely and the LGPD compliance architecture was right from day one. A properly run software Ltda."
// cto · são_paulo, sp
"Our API integration with our ERP was a mess. Guilherme Samuel scoped the problem, built a clean solution and delivered it in six weeks. No surprises, complete NFS-e documentation and the source code is ours. The kind of software partner every growing company needs."
// operations_director · greater_são_paulo
"The workflow automation they built saves our team twelve hours a week. Scoped well, built clean, documented properly. The CNPJ on the contract meant our procurement could process the project without any issues. For custom software in Greater SP South, Guilherme Samuel is our first call."
// founder · itapecerica_da_serra, sp
Describe your software project — what it needs to do, who will use it, any existing systems it needs to integrate with and your timeline. We'll scope it and come back with an honest proposal.
// address
Rua Ubatuba, 64
Vila João Montesano · Itapecerica da Serra — SP
CEP 06853-520 · Brasil
+55 (11) 9 0000-0000
contato@guilhermesamuel.dev
// hours
Mon–Fri: 09:00–18:00 · Sat: 10:00–14:00
Sun: Closed
// cnpj
48.279.891/0001-93