Websites & Web Applications
Professional websites, customer portals, dashboards and complete browser-based business applications.
Laravel · React · TypeScript · FastAPIFull-stack software development
I build complete
digital products.
Marcos Cesar / Full-Stack Product Developer
I design and build websites, SaaS platforms, mobile and desktop applications, APIs, payment systems, AI-powered tools and custom software — from the first idea through to deployment. I can also improve, fix or extend existing software.
New product buildsExisting software improvementsFrom idea to deployment
Product development
What I can build for you
From a new product to an existing application that needs work, I can help shape the requirements, build the right parts and move the software forward.
SaaS & MVP Development
Turn a product idea into working online software, from accounts and dashboards to subscriptions and administration.
Customer portals · Business tools · MVPsMobile Apps
Cross-platform apps for Android and iPhone, connected to backend services, accounts and APIs.
Flutter · FastAPIDesktop Software
Windows applications for specialised business, privacy, networking and operational needs.
C++ · Win32 · CEF / ChromiumAPIs & System Integrations
Connect apps, websites and external services so they can exchange information reliably.
REST APIs · WebSockets · WebhooksSystem Integration & Data Bridges
Build software that connects systems that were never designed to work together.
MT5 market-data bridge · FastAPIPayments & Subscriptions
Add online checkout, recurring billing, payment status and customer access controls.
Stripe · Webhooks · EntitlementsAI & Automation
Add AI-enabled features and automated workflows that handle repetitive tasks inside a product.
AI integrations · Workflow automationAdmin & Customer Portals
Give customers, staff and administrators a clear place to manage accounts and business workflows.
Accounts · Dashboards · Admin toolsFix, Improve or Finish Existing Software
Diagnose bugs, add features, connect services, stabilise unfinished apps and prepare software for release.
Debugging · Integrations · StabilisationDeployment & Production
Move an application toward a live environment with server, domain, database and HTTPS configuration.
Linux · VPS · Nginx · PostgreSQL · RedisFrom a first idea to a working product
One connected process, shaped around your project.
Scope can include each stage or focus on the part your product needs next.
- Requirements
- Interface
- Backend & data
- Integrations
- Testing
- Deployment
Selected projects
Products built and in development.
Four live products and four projects in active development. Each case study distinguishes shipped product work from current development scope.
NovaBridgeVPN
A VPN service with desktop and mobile applications that connect customers to centrally managed VPN servers.
TakeAIEmployee
A SaaS product designed to let small businesses create AI employees and AI-powered customer assistants.
TestiFollow
A service that helps businesses collect customer testimonials, review submissions and display approved testimonials on their websites.
ETAApply
An independent online service that guides travellers through a structured UK ETA application-assistance process.
BLACK
A privacy-focused Windows web browser being developed as a native desktop application.
NVBGlobal
A private web trading platform and evaluation system where users can view markets, place simulated trades and track challenge rules and performance.
Fans24Hours
A creator platform in development with creator profiles, subscriber-only content, private media and moderation workflows.
GetTraffic365
A marketing platform for analysing websites, organising campaigns, distributing content and tracking visits and conversions.
Tools & technologies
A practical toolkit.
For technical teams, here are some of the technologies I’ve used across these products. The case studies show where each stack is applied.
Frontend
ReactTypeScriptJavaScriptFlutterBladeTailwind CSSHTML / CSS
Backend
LaravelPHPFastAPIPythonNode.jsFastify
Data
PostgreSQLRedisSQLAlchemyEloquentAlembic
Infrastructure & Integrations
LinuxNginxREST APIsWebSocketsStripeGit / GitHub
Specialised
C++20Win32CEF / ChromiumWireGuardWindows Filtering PlatformMT5 market-data integration
About Marcos
One developer. Complete product capability.
I’m an independent developer who builds practical software products across SaaS, AI-enabled applications, APIs, payments, data systems and cloud infrastructure.
I work across the product lifecycle: understanding requirements, designing a solution, building its interface and backend, connecting data and services, testing, deployment and ongoing improvements. That includes products taken into production.
Practical engineering, reliable integrations and software built around real requirements.
Freelance development
Have something you want to build?
Whether you’re starting with an idea, improving an existing product or trying to finish a project that’s stuck, tell me what you need.