Raphael Serafim

Senior Software Engineer · Node.js · TypeScript · React · APIs & Integrations

Summary

Senior Software Engineer with 9+ years of experience designing and shipping scalable web platforms, APIs and developer tools. I build and run Wame API, a multi-channel messaging API (WhatsApp, Instagram, Messenger, Telegram) with 50,000+ instances created, and I have delivered AI-powered systems, blockchain platforms and financial integrations end to end, from architecture to production. Strong in Node.js, TypeScript, React, PHP and Python, with hands-on ownership of infrastructure, performance and reliability.

Experience

Senior Software Engineer
Wame API | January 2019 - Present
Building and maintaining Wame API, a messaging platform that gives developers one API key, one webhook format and one SDK across WhatsApp, Instagram, Messenger and Telegram.
  • Grew the platform to 50,000+ instances created, handling around 20,000 requests per hour with 99.9% uptime.
  • Supports both the official Meta Cloud API and QR code-based WhatsApp connections, including coexistence (the same number on the API and the WhatsApp mobile app).
  • Back end in Node.js and TypeScript on a microservices architecture: Docker containers for isolated instances, Redis queues, MongoDB and SQL storage, running on AWS with Cloudflare at the edge.
  • Built the React dashboards, Stripe billing, and complete Swagger/OpenAPI documentation with Postman collections and llms.txt.
  • Published official SDKs for Node.js (npm) and PHP (GitHub), used by hundreds of developers.
  • Shipped AI and automation integrations: an MCP server so Claude and other AI assistants can send and read messages, plus n8n and Chatwoot integrations.
Senior Software Developer
Hadronlink Connectus | Toronto, Canada | November 2025 - September 2026
Freelance · Remote
Senior Software Developer
Lysterium | Toronto, Canada | February 2025 - June 2025
On-site
Main project: AI-based technical visit scheduling system, where an AI assistant handles phone calls, asks about the customer's equipment and books the technical visit automatically.
  • Owned the full back end and end-to-end API architecture in Node.js, including Twilio integration for automated calls.
  • Built an AI server with Ollama and a Python API for intelligent scheduling and device information collection.
  • Designed and implemented other custom software solutions, including APIs and web systems in Node.js and React.js.
Senior Software Developer
CJ Technologies | Toronto, Canada | April 2023 - October 2024
On-site
Main project: World of Blast, a decentralized gaming platform on the Blast network (Ethereum L2).
  • Led back-end development in Node.js and PHP, including the integration with the Blast network.
  • Designed and deployed Solidity smart contracts: battle logic, NFT collections and an ERC-20 token for the platform's economy.
  • Implemented the front-end MetaMask integration for seamless on-chain interactions.
  • At launch, the platform processed over $40,000 in transactions.
  • Optimized database queries to improve performance and scalability, working with cross-functional teams on new features.
Software Developer
CACHE SISTEMAS | Guarantã do Norte, Brazil | December 2017 - November 2022
On-site
Designed and built the entire college management system for UNIFAMA, owning architecture, back end and front end.
  • Student, class, course, enrollment and financial management in a single platform.
  • Bank integration for automatic invoice generation, plus online contract signing: students sign digitally and invoices are generated automatically.
  • Saved approximately BRL 100,000 per semester by eliminating manual printing and processing of payment slips.
  • Took the project from concept to delivery early in my career, significantly improving operational efficiency.

Open Source Projects

I maintain open-source tools that help developers and companies ship faster: More on github.com/raphaelvserafim.

Contact

✉️ contact@raphaelvserafim.com
🌐 raphaelvserafim.com
💻 github.com/raphaelvserafim
💬 api-wa.me
📍 Toronto, ON, Canada

Skills

Languages
TypeScript · JavaScript · PHP · Python · SQL · Solidity
Back End
Node.js · Laravel · REST APIs · Webhooks · Microservices · Socket.IO · Ratchet · Serverless
Front End & Mobile
React · Next.js · React Native · Electron · HTML5 · CSS · Tailwind · Bootstrap
Data
MySQL · MongoDB · Redis · Firebase · Database Design & Optimization
Cloud & DevOps
AWS · Cloudflare · Docker · Linux · CI/CD · Git / GitHub
Messaging & Integrations
WhatsApp (Meta Cloud API) · Instagram · Messenger · Telegram · Twilio · Stripe · Banking & Pix
AI
LLM Integration · MCP Servers · OpenAI · Ollama · n8n · Machine Learning
Blockchain
Smart Contracts · Web3 · MetaMask · NFTs / ERC-20 · DeFi
Practices
Software Architecture · System Design · Testing · Security Best Practices · Agile · SEO

Languages

Portuguese Native
English Intermediate

Education

Bachelor's Degree
Information Systems
UNIFAMA
Graduated in 2020

Certifications

Driving License
Social Worker License

Personal Information

Willing to relocate: Yes