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I'm a Senior Full-Stack AI Developer with 7+ years of software engineering experience, specializing in building AI-powered SaaS platforms, intelligent automation systems, and scalable web applications. I help startups and businesses turn ideas into production-ready AI products that generate revenue and scale efficiently. Over the years, I've built and deployed: - End-to-end SaaS products (MVP -> Scale) - LLM & GPT-powered applications - AI automation system that reduce operational costs - High-performance frontend & backend architectures - Secure APIs & third-party integrations - Cloud-native infrastructure & DevOps pipelines I combine strong engineering fundamentals with deep AI integration expertise - meaning I don't just build features, I built scalable AI products. If you are looking for a developer who understands architecture, performance, and business impact - let's build something exceptional.

I’m a backend and full-stack engineer. I spend most of my time on slow systems, broken search, and things that shouldn’t require a human sitting there clicking through spreadsheets. Some numbers from a platform with 1.4M+ users: • Migrated 100+ production queries to a new data warehouse. Average execution went from 190s to 2s. • Built a search relevancy pipeline (Elasticsearch + cross-encoder reranking). Went from 80% to 96% relevancy, measured through iterative benchmarks. • Automated a report that took someone 2 hours of pulling from multiple spreadsheets. Runs in 5 minutes now. Day to day I work across: • Backend and APIs — Django, FastAPI, Node.js/Express, REST, WebSockets • Search — Elasticsearch, semantic search, reranking pipelines • Data — BigQuery, PostgreSQL, Redis, Airbyte, ETL, query tuning • Automation — Python/Selenium, Puppeteer, workflow scripts • Infra — Docker, CI/CD, Heroku, Cloudflare • Some frontend when needed — React, TypeScript I scope upfront and flag trade-offs before they become problems. I reply fast (under 30 minutes during work hours) and I don’t disappear mid-project. Top Rated on Upwork.

🚀 Experienced Software Engineer | Java, Spring & Kotlin Specialist | Oracle-Certified | 10+ Years in Web & API Development Hi, I'm Daniel — a passionate software engineer with over a decade of hands-on experience in designing, developing, and delivering robust solutions using Java, Kotlin, Spring Boot, and RESTful APIs. I’m also Oracle-certified and have contributed to a wide range of successful projects across industries, from startups to large enterprises. 💻 Tech Stack Highlights Java, Kotlin, Spring Framework (Boot, MVC, Security) Angular & React for modern web interfaces AWS for cloud infrastructure JasperReports for reporting solutions PostgreSQL, MySQL, and other RDBMS AI Agents (Augment, Cortex) 🌐 My background includes full-stack development (Desktop and Web), integration with cloud services, and leading feature development in agile environments. Whether it's building scalable microservices, modern APIs, or intuitive UIs, I bring technical depth and adaptability to every project. ✅ Open to remote opportunities ✅ Fluent in English and Portuguese ✅ Strong communication and teamwork

I'm a backend developer with over 15 years of experience in building scalable and secure web applications, specializing in Ruby on Rails. I have solid expertise in Linux infrastructure, automation, and cloud platforms (AWS, Azure). I'm currently pursuing a PhD in Computer Science at UFPE, with a focus on distributed systems and virtual machine performance. I'm looking to contribute to challenging and purpose-driven projects.

Need a senior architect who designs business-focused solutions and handles backend AI pipelines, RAG, or complex ETL at scale? Whether Python, Node.js, Go, or many others, I've shipped production systems for 16+ years, including: HIPAA-compliant platforms, identity infrastructure, and LLM-powered APIs on AWS. What sets me apart: behind my backend specialization, speed, quality, and cost stay balanced because you see every trade-off and make the call with me. I don't just wire up an API. I architect the data flow, own the cloud infrastructure, and handle complex auth (OAuth2, OIDC, SAML),so you don't need to manage different contractors. With Top Rated Plus status and $150K+ earned across 7 active contracts, my clients keep coming back for two simple reasons: I communicate clearly, and I ship on time. 🐍 Python backends — FastAPI, Flask, Django, async workers, parallelism ⚡ Node.js / TypeScript APIs — Express.js, Nest.js, REST, GraphQL, Supabase integrations 🐹 Golang services — high-performance APIs, concurrency, microservices 🤖 AI & RAG pipelines — LLM orchestration, vector search, embedding workflows 📊 ETL & data engineering — GCP BigQuery, PostgreSQL, MongoDB, Kafka, RabbitMQ, SQS ☁️ Cloud & DevOps — AWS (Lambda, EC2, S3, Step Functions), GCP, Docker, Kubernetes, Helm 🔐 Identity & Auth — OAuth2, OIDC, SAML, OpenID Connect 🌐 Full-stack when needed — React.js, Next.js, Redux, Vue.js ✅ Top Rated Plus on Upwork — top 3% of talent ✅ 16+ years of software development experience ✅ Led HIPAA-compliant mental health platform as sole technical owner (Node.js + AWS) ✅ Redesigned inbound identity module of Gluu, open-source IAM platform (SAML → OpenID Connect proxy) ✅ Certified: Programming with Google Go (UC Irvine) | Cloud Native Dev with Node.js, Docker & Kubernetes ✅ Acted as Product Lead and CTO — I understand business context, not just code Send me a message with what you're trying to build or fix — a single sentence is enough to start. I'll tell you how I'd approach it and the trade-offs to expect, so you can evaluate the fit before we scope anything. Detailed spec or just a rough idea, send it over.

12+ years building software for JPMorgan Chase, Cisco, Avaya, and Ford. 12,400+ hours on Upwork alone. AI-augmented engineer running parallel agents with Claude Code and Codex. Production-grade output at a pace that would normally require a team. Built ML-powered palm biometrics kiosk apps for Keyo (Series A, $30M+ raised, thousands of devices deployed, backed by Netflix co-founder), deployed at JPMorgan Chase. Shipped AI-driven identity verification SDKs at Journey.ai (Gartner Cool Vendor, Zero Knowledge Network, multi-modal biometrics with 99.9999% accuracy) used by Cisco Webex and Avaya, and on prototypes for unreleased Ford partnerships. Worked on an AI teaching assistant active in 125+ UK classrooms, 40,000+ questions answered by AI. Led the development of the POV Disposable Camera Android app (3M+ users, 4.9 stars). AI feature integration (OpenAI, Anthropic, Azure), web applications (Next.js, TypeScript), full-stack products with Firebase, Supabase, and Cloud Functions, Kotlin Multiplatform apps, app refactoring and modernization, native Android and AndroidTV apps (Kotlin, Jetpack Compose), IoT and kiosk applications, and video streaming solutions (ExoPlayer, HLS). Software engineer building mobile apps, web apps, and backend systems. Engineering Manager and CTO experience. Delivering multiple times faster than traditional development without sacrificing code quality or architecture. "Excellent development manager. Writes clean code, good eye for design, successfully managing a team of mobile developers. A core manager in our organisation." - Chris Cooper, CEO at NeoMatrix "Takes initiative and drives the product forward, not only through technical skills but understanding the what and the why of what we're building." - Todd Zusman, Director of Engineering at Journey.ai "Strong technical skills, excellent communication, a true team player and great manager. Architect of a complex cross-platform project. We'd happily work with him again." - Cayetana Polanco, CPO at Keyo "A rare find and very dedicated engineer, team lead and manager. Thiago always delivers." - Al Calendario, Director of Integration at Keyo "Accomplished all tasks very well, sometimes beyond expectations. In command of the Android API, managed tasks with little supervision, keen interest in the business purposes of the app." - Stephen Hosking, CEO at NoPowerTXT "Communication is impeccable, incredibly reliable, very detail-oriented. The kind of leader who grows through adversity and never loses sight of the people." - Lynda Yang, SHRM-SCP at Untitled Shows Kotlin, Java, TypeScript, Python Jetpack Compose, MVVM/MVI, Hilt, Room, Retrofit, Coroutines, ExoPlayer Kotlin Multiplatform Firebase (Firestore, Cloud Functions, RTDB), Node.js, Next.js Claude Code, Codex, OpenAI API, Anthropic API, Azure AI GitHub Actions CI/CD, automated code review, multi-worktree workflows PostHog, Crashlytics, Sentry Check the portfolio below and send a message. Happy to discuss your project.