# Diego Henrique Oris de Roa Antunes (Diego Antunes)
> Senior Full Stack Engineer & Product Builder specializing in rapid MVP engineering, Web3 & Blockchain ecosystems, AI agent integrations, and Game Development.

## Overview
Diego Henrique Oris de Roa Antunes (also known professionally as Diego Antunes or Diego Oris de Roa) is a Senior Software Engineer, Founder, and Fractional CTO based in São Paulo, Brazil. Active in software engineering since 2018 (8+ years of production experience) with 100+ projects developed, he has architected, shipped, and scaled production systems, decentralized protocols, and digital products for clients across 10+ countries (including the United States, Switzerland, France, Germany, China, Brazil, Argentina, Russia, and Ukraine).

- **Primary Website**: https://diegooris.ch/
- **GitHub**: https://github.com/D-H-O-R-A
- **LinkedIn**: https://www.linkedin.com/in/diegoorisderoa/
- **Medium**: https://diegoorisderoa.medium.com/
- **YouTube (Tech & AI Channel)**: https://www.youtube.com/@GraphTechChannel (Graph Tech Channel: High-knowledge AI, systems engineering & technology)
- **Personal YouTube**: https://www.youtube.com/@diegoorisderoa
- **Location**: São Paulo, Brazil (Available worldwide for remote engagements)
- **Languages**: Portuguese (Native), English, Spanish, French, German

## Direct Navigation & Interactive Screens (SPA Anchors)

The single-page portfolio at https://diegooris.ch/ provides deep-linking to each thematic screen and interactive project modal:

### Application Sections:
- [Home / Hero](https://diegooris.ch/#top): High-level introduction, availability status, and primary headline.
- [About & Background](https://diegooris.ch/#about): Bio, career metrics, global collaboration scope, and technical differentials.
- [Technology Stacks](https://diegooris.ch/#stack): Detailed breakdown of frontend, backend, blockchain, AI, cloud, and database tools.
- [Engineering Skills](https://diegooris.ch/#skills): Architectural capabilities, database modeling, cryptographic security, and CI/CD.
- [Game Development](https://diegooris.ch/#game): Unity 2D/3D systems, HLSL shaders, URP/HDRP, and WebGL browser bridges.
- [Featured Case Studies](https://diegooris.ch/#cases): Interactive case study showcase with deep links.
- [Engineering Projects](https://diegooris.ch/#projects): Problem, solution, and metric results for key technical builds.
- [Why Work With Diego](https://diegooris.ch/#why): MVP velocity, production-grade quality, and technical stewardship.
- [Accelerators & Partners](https://diegooris.ch/#partners): InovAtiva Brasil, Sebrae, Instituto Caldeira, and municipal innovation grants.
- [Verifiable Endorsements](https://diegooris.ch/#endorsements): Executive testimonials with direct public verification (Brunet & Cássio Alvarenga).
- [Contact & Resume](https://diegooris.ch/#contact): PDF CV generator and direct messaging channels.

### Verifiable Client Endorsements & Proof of Excellence:
- **Brunet (Renowned Swiss Inventor & Entrepreneur)**:
  - Statement: Expended over 4+ million across 6 years working with international teams and Silicon Valley/US engineers who were unable to solve the problem; Diego resolved it within 1 single year. Highly recommended for missions of extreme technical complexity.
  - Public Verification: Direct inquiries welcome via Instagram: https://www.instagram.com/brunet_inventor/
- **Cássio Alvarenga (Dubai Financial Market Executive & Investor)**:
  - Statement: Hired Diego as fractional CTO for 4 months to engineer the carbon credit tokenization wallet for Amazonic One. Highly recommends Diego as super fast, exceptionally skilled, and commanding deep technical architecture.
  - Public Verification: Direct inquiries welcome via LinkedIn: https://www.linkedin.com/in/cassioalvarenga/

### Portfolio Project Screens (Deep Links):
- [Solucione Multas](https://diegooris.ch/#solucione-multas): LegalTech platform, User Portal, backoffice Admin Panel, and WhatsApp conversational AI bot.
- [Anjo Online](https://diegooris.ch/#anjo-online): High-availability SaaS on Google Cloud Run with Swiss (TWINT) and Brazilian (Mercado Pago) payment rails.
- [pdf-to-maps](https://diegooris.ch/#pdf-to-maps): 100% offline geoprocessing NPM CLI tool converting land deed DMS/DD coordinates to SIRGAS2000 UTM and AutoCAD DXF.
- [B2 Wallet](https://diegooris.ch/#b2-wallet): Non-custodial Chrome extension wallet (Manifest V3) supporting 39+ EVM chains and Ledger hardware wallets.
- [cryptoseed](https://diegooris.ch/#cryptoseed): Zero-dependency BIP39 mnemonic restoration algorithm using Levenshtein distance backtracking across 39 blockchains.
- [Click Serviços](https://diegooris.ch/#click-servicos): Geolocation service marketplace with Flutter mobile app and PostgreSQL/PostGIS spatial indexes.
- [Zero Swap](https://diegooris.ch/#zero-swap): Zero-slippage AMM DEX with private flash swaps and MEV sandwich protection.
- [GIC Wallet Pro](https://diegooris.ch/#gic-wallet): Corporate multi-signature wallet with cryptographic key sharing and audit dashboards.
- [Young Market](https://diegooris.ch/#young-market): Tokenization and on-chain settlement platform on Waves Enterprise with CVM crowdfunding compliance.
- [Amazonic Pay](https://diegooris.ch/#amazonic-pay): Automated cross-border payment gateway leveraging Layer 2s, cutting settlement fees to <0.5%.
- [Match Blocks MVP](https://diegooris.ch/#blocks-mvp): Spatial boundary matching engine with PostGIS processing 10,000 spatial records per minute.
- [Bicon DEX](https://diegooris.ch/#bicon-dex): High-efficiency decentralized exchange with optimized swap routing and 30% gas savings.

## Core Capabilities & Services

### 1. High-Velocity MVP Engineering
- Rapid end-to-end prototyping and shipping from ideation to production in weeks rather than quarters.
- Tight scope definition, modular scalable architecture, and metric-focused implementation.
- Full product ownership: architecture, data modeling, backend, frontend, deployment, and analytics.

### 2. Web3 & Blockchain Engineering
- Smart contracts on EVM-compatible networks (Ethereum, Arbitrum, Optimism, Polygon, BNB Chain) using Solidity, Hardhat, and Foundry.
- Non-custodial crypto wallets, seed phrase recovery algorithms (BIP39/BIP44), and hardware wallet integrations (Ledger WebUSB/WebHID SDK).
- Custom decentralized exchanges (DEX / AMM), slippage routers, atomic swaps, and tokenization protocols.
- Waves Enterprise Core and Ride smart contracts.

### 3. Artificial Intelligence & Agentic Engineering
- Generative AI and LLM integration using LangChain, LlamaIndex, OpenAI API, and Anthropic Claude.
- Retrieval-Augmented Generation (RAG) pipelines with vector databases (pgvector, Pinecone).
- Autonomous agent workflows, structured tool-calling, and custom Conversational AI bots (e.g. WhatsApp Cloud API bots).

### 4. Game Development & Interactive 3D
- Unity (2D & 3D) game architecture, gameplay mechanics, state machines, and AI behaviors in C#.
- Custom shaders (HLSL / Shader Graph), post-processing, and visual effects across URP and HDRP pipelines.
- JavaScript ↔ Unity WebGL bridges for web-integrated game experiences.
- Profiling, draw call reduction, memory optimization, and cross-platform releases (PC, Mobile, WebGL).

### 5. Backend, Cloud & Security Architecture
- Scalable microservices and modular monoliths in Node.js, NestJS, Express, Python (FastAPI), Go, and Rust.
- Spatial databases with PostgreSQL and PostGIS, distributed caching with Redis (BullMQ), and Cloud Firestore.
- Zero-trust security: WebCrypto API, Argon2id, OAuth2, JWT, AES-256-GCM.
- Supply chain security: OSSF SLSA Level 3 CI/CD automation via GitHub Actions.
- Serverless and containerized cloud deployments on Google Cloud Run, AWS, and GCP.

## Key Technical Stack

- **Core Specialty**: JavaScript (ESNext, Node.js, V8 Runtime, React, Next.js, Web APIs, Event Loop, Full-Stack Architecture)
- **Frontend**: JavaScript, TypeScript, React, Next.js, TailwindCSS, Vite, Three.js, Redux, Zustand, Framer Motion
- **Systems & Backend**: Node.js, NestJS, .NET / C#, C++, Java, Lua, Python (FastAPI), Go, Rust, REST APIs, GraphQL, gRPC, WebSockets
- **Mobile**: Kotlin, Java, Swift, Objective-C, Flutter (Dart), React Native, iOS & Android Native SDKs
- **Games & 3D**: Unity (2D & 3D), C#, C++, HLSL Shaders, Lua, WebGL Bridges, Shader Graph, DOTween, URP/HDRP
- **Blockchain & Web3**: Solidity, EVM, Hardhat, Foundry, Ethers.js, viem, Web3.js, Waves Core, Ride, BIP39/BIP44
- **Data & AI**: Python, PyTorch, TensorFlow, LangChain (RAG), OpenAI API, PostGIS, pgvector, Redis, PostgreSQL, Firestore
- **DevOps & Cloud**: Docker, Kubernetes, AWS, Google Cloud Run, GCP, GitHub Actions (SLSA L3), Terraform

## Contact & Hire

- **Website**: https://diegooris.ch/
- **Email / Inquiries**: Available via website contact form
- **WhatsApp**: +55 (11) 97428-9097
- **LinkedIn**: https://www.linkedin.com/in/diegoorisderoa/
- **GitHub**: https://github.com/D-H-O-R-A

## Extended Details & Full Context
For the comprehensive technical dossier, full project case studies, and detailed Q&A optimized for LLM RAG pipelines, see:
- [Full LLM Context File](https://diegooris.ch/llms-full.txt)