I build production-oriented SaaS products, automation platforms, APIs, dashboards, and AI-powered tools with a strong focus on architecture, performance, usability, and business impact.

Portfolio • DevFlow Labs GitHub • LinkedIn • Email

• 💻 Fullstack Developer focused on React, Next.js, Node.js, TypeScript, Python and PostgreSQL
• 🧠 Founder & Product Engineer at DevFlow Labs
• 🛠️ Creator of products such as Investiga+, ApplyFlow, WhatsApp Platform, DevFlow Financeiro, and Career Suite
• ⚙️ Experience with REST APIs, authentication, JWT, Prisma, Docker, CI/CD, webhooks and third-party integrations
• 🤖 Practical experience applying AI/OpenAI to product workflows, automation, documentation, ATS analysis and productivity tools
• 🎓 B.Sc. in Computer Science from Centro Universitário FEI
• 📍 Based in Santos, São Paulo, Brazil
• 🌎 Advanced English — available for remote opportunities

Product lab focused on SaaS, automation, AI-assisted workflows and business tools.

GitHub Organization: https://github.com/devflow-modules
Portfolio: https://devflowlabs.com.br

Stack: Next.js, TypeScript, React, Tailwind CSS, Node.js, Prisma, PostgreSQL, Supabase, Stripe, OpenAI, WhatsApp Cloud API, Vercel, GitHub Actions.

Focus: product architecture, multi-tenant SaaS, automation, AI workflows, billing, dashboards and integrations.

SaaS platform for company data lookup and CNPJ analysis, built with secure authentication, API integrations, cache, history, webhooks and automated tests.

Repository: https://github.com/devflow-modules/investiga-mais
Live: https://investigamais.com

Stack: Next.js, React, Node.js, Express, Prisma ORM, PostgreSQL, Chakra UI, Docker, Jest, GitHub Actions.

Focus: secure authentication, company data analysis, external API integration, cached searches, usage history and SaaS-ready architecture.

Local-first workflow assistant for job applications, focused on LinkedIn Easy Apply productivity, job tracking, metrics and candidate intelligence.

Stack: Chrome Extension MV3, Next.js, TypeScript, local storage, automation helpers, privacy-first architecture.

Focus: privacy-first automation, local-first data, candidate productivity and application tracking.

Multi-tenant WhatsApp Cloud API platform for customer support, automation, AI replies, operational metrics, activation control and billing.

Stack: Next.js, TypeScript, Prisma, PostgreSQL, Meta WhatsApp Cloud API, Stripe, OpenAI, role-based access, webhooks.

Focus: inbox operations, AI-assisted replies, usage-based billing, activation workflows and production monitoring.

Financial management product with health score, insights, monthly checklist, categorization and operational dashboard.

Stack: Next.js, TypeScript, Prisma, PostgreSQL, Tailwind CSS, product analytics and business rules.

Focus: financial health score, actionable insights, monthly routines and user-oriented dashboards.

AI-assisted career tools for resume analysis, job matching, interview preparation and application workflows.

Stack: Next.js, TypeScript, local-first analysis, OpenAI API, ATS-style scoring, documentation as product.

Focus: resume matching, job analysis, interview preparation and AI-assisted career workflows.

React.js • Next.js • TypeScript • JavaScript • Tailwind CSS • Chakra UI • ShadCN UI • Styled Components • HTML5 • CSS3 • Framer Motion

Node.js • Express.js • Python • FastAPI • Prisma ORM • REST APIs • Webhooks • JWT • Cookies HttpOnly • Authentication & Authorization

PostgreSQL • SQLite • Supabase • Redis • Docker • Vercel • Railway • Render • GitHub Actions • CI/CD

Jest • Playwright • Selenium • Testing Library • Pytest • RPA • API testing • E2E validation

OpenAI API • WhatsApp Cloud API • Stripe • ReceitaWS • Webhooks • CRM integrations • Automation workflows

• Building scalable SaaS products under DevFlow Labs
• Improving AI-powered product workflows
• Strengthening frontend architecture with Next.js, React and TypeScript
• Creating automation and productivity tools with real business use cases
• Growing as a Fullstack/Product Engineer for remote and international opportunities

• LinkedIn: https://www.linkedin.com/in/gustavo-marques-00
• GitHub: https://github.com/gustavomarques00
• DevFlow Labs GitHub: https://github.com/devflow-modules
• Email: gustavomarquesmm@gmail.com
• Portfolio: https://devflowlabs.com.br