Hire Vetted Web Application Engineers at Upstaff - Page 5

• 7+ years of experience, specializing in full-stack development with React, Vue, Next.js, Node.js, NestJS, and TypeScript.
• Expertise in architecting dashboards, multi-currency payment forms, and microservices using Prisma, PostgreSQL, and MongoDB.
• Skilled in state management (Zustand, Redux, TanStack Query), real-time data handling (Socket.io, WebSockets), and performance optimization (Redis caching, code splitting).
• Background in test-driven development with Jest, React Testing Library, and Cypress, plus containerization and AWS deployment.
• Skilled in designing role-based access systems and integrating OAuth 2.0, JWT, and complex API workflows in distributed architectures.

• Full Stack Engineer with 20+ years of experience in scalable web platforms, specializing in React, TypeScript, Node.js, and cloud-native architectures (AWS, GCP, Azure).
• Expertise in designing modular frontend architectures, reusable component libraries, and backend microservices with performance optimization and high-load scalability.
• Experience integrating AI-assisted development workflows using LLM APIs and agentic coding tools.
• Background in system design, distributed systems, event-driven architecture, and secure financial/payment processing platforms with multi-provider integrations.
• Knowledge of SDLC, CI/CD automation, DevOps practices, and engineering leadership in Agile environments.

• Full Stack Engineer with 10+ years of experience delivering scalable SaaS platforms and cloud-native systems using React, TypeScript, Python, FastAPI, Django, Node.js, PostgreSQL, Redis, and AWS.
• Proven expertise in legacy system modernization, reducing API response times from 3s to under 1.8s by migrating C#/.NET services to modern microservices architectures.
• Strong background in system design, distributed systems, event-driven workflows with Kafka, Celery, and Redis, improving performance and reducing blocked API requests by 40%.
• Skilled in cross-platform development with React Native and Expo, cutting duplicated implementation by 25% while maintaining consistent UX across web and mobile.

Senior Front-End Developer (React Native mobile / React web) with 10+ years of experience. Skilled at JavaScript, TypeScript, and React. I’ve worked on various projects and have extensive expertise. I have experience developing projects from scratch through to market release.

• Backend engineer with expertise in NestJS, Node.js, and TypeScript, specializing in building secure, scalable REST APIs and auth systems
• Proven experience in Web3 integrations, smart contract auditing on Celo, and blockchain technologies including Solana, Farcaster SDK
• Skilled in container orchestration and infrastructure automation using Docker SDK, docker compose, and Caddy for zero-downtime deployments.
• Developed AI-powered platforms leveraging Google Gemini and Elasticsearch for real-time payment reconciliation and natural language query parsing into SQL.
• Strong focus on clean architecture, security best practices, and system design demonstrated through multiple end-to-end projects.

Software Developer with over 5 years of experience building scalable APIs and full-stack web applications using .NET Core and React.js. Experienced in designing efficient database solutions with MySQL and SQL Server, integrating third-party systems, and optimizing application performance. Proven track record of delivering production-ready systems for small to medium-sized businesses, with a strong emphasis on clean architecture, maintainable code, and business-driven solutions. Comfortable working in distributed teams using Git-based workflows.

• 18+ years in software engineering with expertise in C++, Qt/QML, Python, Django, Node.js, React, and AI integration using OpenAI APIs.
• Proven track record in building end-to-end production software including embedded automotive HMI, multi-tenant SaaS platforms, and AI-driven web applications.
• Led design and development of complex systems such as multi-app payroll/HRMS platforms, AI-powered recruitment automation, and supply-chain optimization backends.
• Strong background in database management (PostgreSQL, MySQL, SQL Server), cloud infrastructure (Docker, GCP Cloud Run), and REST API design.

• 18+ years in software engineering with expertise in C++, Qt/QML, Python, Django, Node.js, React, and AI integration using OpenAI APIs.
• Proven track record in building end-to-end production software including embedded automotive HMI, multi-tenant SaaS platforms, and AI-driven web applications.
• Led design and development of complex systems such as multi-app payroll/HRMS platforms, AI-powered recruitment automation, and supply-chain optimization backends.
• Strong background in database management (PostgreSQL, MySQL, SQL Server), cloud infrastructure (Docker, GCP Cloud Run), and REST API design.

• Over 4 years of experience in 1 outsourcing and 1 outstaffing company.
• For the last 3 years, I have been working on:
• updating legacy code to smth normal and usable (PHP/Laravel + Angular)
• adding new features to both app/api of e-commerce project (PHP/Laravel + Angular)
• creating a new project from scratch (Python/FastAPI + Angular)
• adding new features to the dating project (Python/FastAPI + Angular)

• Over 10 years of expertise in Ruby on Rails and PostgreSQL, specializing in scalable web applications and performance optimization.
• Proven track record in designing modular microservices and implementing automated KYC systems, enhancing verification success, and reducing manual workload.
• Extensive experience with Angular (5+ years) and React for full-stack development, delivering high-traffic social networks and CRM platforms.
• Skilled in REST/GraphQL APIs, real-time high-concurrency backend architectures, and cloud technologies including AWS and Docker.

• Proficient in full-stack development with expertise in TypeScript, React, Rust, Swift, and backend technologies including Prisma, PostgreSQL, and Bun, demonstrated through building scalable CMS, native macOS apps, and terminal tools.
• Skilled in asynchronous programming, Rust backend refactoring, and cross-platform development using Tauri and React Native, enhancing startup latency and memory usage.
• Hands-on with CI/CD pipelines, AWS deployment, and monitoring to maintain 99.9% uptime, alongside advanced automation integrating AppleScript and AI-driven transaction parsing.

• Over 6 years of experience in full-stack development, AI/ML engineering, and cloud-native architecture, with a BSc. in Computer Engineering from University of Ghana
• Proficient in JavaScript, TypeScript, Python, and frameworks like React, Next.js, Node.js, and Express, delivering scalable SaaS and mobile solutions
• Led end-to-end product development as CTO, architecting high-availability systems with 99.9% uptime and automated CI/CD pipelines on AWS and GCP
• Skilled in agile methodologies, test-driven development, and DevOps practices, optimizing cloud workflows and ensuring robust, maintainable codebases

• 7+ years of experience in full-stack development using Node.js, TypeScript, Vue.js, and PostgreSQL for scalable SaaS and AI-powered platforms.
• Skilled in database design, query optimization, and managing large-scale datasets for high-performance applications.
• Experienced in AI/LLM integration using OpenAI and Anthropic APIs for automation and intelligent workflows..
• Strong knowledge of algorithms, data structures, software architecture, and modern design patterns.
• Proficient in AWS, Azure, Docker, CI/CD, and cloud-native deployments for enterprise systems.

• 5+ years of freelance experience building custom WordPress platforms with Python/PostgreSQL backends and AI-powered features.
• Skilled in FastAPI, ETL automation (Pandas, Airflow), and serverless deployments on AWS Lambda.
• Experienced in WordPress plugin/theme development, Gutenberg blocks, performance optimization, and access control systems.
• Proficient in AI/LLM integration, prompt engineering, summarization, and OpenAI/Anthropic APIs.
• Strong frontend skills with JavaScript, DataTables, Chart.js, and remote collaboration across EST time zones.

• 5+ years of experience building custom WordPress platforms
• Expertise in building REST APIs with FastAPI, ETL pipelines using Pandas and Airflow, and deploying serverless applications on AWS Lambda.
• Skilled in developing WordPress plugins, themes, and Gutenberg blocks for subscriber-based platforms, with expertise in role-based access control and performance optimization.
• Proficient in AI/LLM integration including prompt engineering, natural-language querying, and summarization using OpenAI and Anthropic APIs.
• Strong frontend development skills with JavaScript, DataTables, and Chart.js for dynamic, interactive data visualizations and reporting interfaces.

• 10+ years of experience delivering scalable SaaS platforms and cloud-native systems using React, TypeScript, Python (FastAPI, Django), Node.js, and AWS.
• Proven expertise in legacy system modernization, reducing API response times from 3s to under 1.8s by migrating C#/.NET services to modern microservices.
• Strong in system design, distributed systems, event-driven architectures with Kafka, Celery, Redis, and performance optimization.
• Skilled in full SDLC ownership, CI/CD pipelines, containerization (Docker, Kubernetes), and infrastructure as code for reliable cloud deployments.

Senior Software Engineer with 10+ years of experience building scalable backend and data-intensive systems. Focus on clean architecture, and real-world impact

• Full-Stack Engineer with 3+ years of experience in scalable SaaS and AI-driven platforms, specializing in React, Next.js, Node.js, GraphQL, and asynchronous event-driven systems.
• Proficient in integrating OpenAI APIs, RAG pipelines, vector databases, and secure authentication (Auth0, OAuth) for enterprise-grade, multi-tenant architectures.
• Cross-platform apps serving 1,500+ users with optimized APIs, message queues, and AWS cloud infrastructure.
• Skilled in modular component design, performance optimization, CI/CD pipelines, and cloud using AWS, Docker, and Supabase.
• Bachelor’s in Computer Science with achievements including ICPC Asia ranking and leadership roles in developer communities.

• Over 9 years of experience in software development with a focus on Java 8/17 back-end applications, utilizing Spring Boot and HAPI FHIR frameworks.
• Proficient in designing and developing APIs, business logic, and database solutions using PostgreSQL, Kafka, Docker, and Liquibase in healthcare and finance sectors.
• Strong expertise in object-oriented design, design patterns, and software development lifecycle within Agile methodologies including Scrum and Kanban.
• Hands-on experience with HL7/FHIR protocols and standards, contributing to protocol converter projects for healthcare applications.

• Senior React Native engineer with 7+ years building mobile apps with React Native (Expo, CLI) and React, focusing on scalable app architecture and feature delivery.
• Experience with video features in social and communication apps (live streams, video calls, feed-based consumption), including HLS playback, buffering, and performance tuning on mobile.
• Worked on mobile-first video UX: smooth playback, fast loading, adaptive bitrate, and seamless navigation between video items.
• Hands-on with monetization, analytics, and integrations (Firebase, GraphQL), plus mentoring and collaboration across product and backend teams.

• Backend Engineer with 4+ years of experience in Java, TypeScript, and Python, working with Spring Boot and NestJS in microservices architectures.
• Experience in healthcare integrations: worked with Epic/MyChart, HL7 (R4) data processing and conversion into internal services.
• Built and maintained backend services handling high-load systems using Kafka, Redis, Cassandra, and PostgreSQL.
• Developed integration services for third-party systems, including batch processing and REST-based communication in AWS environments.

• Engineering background from IIT Patna with a strong CGPA of 8.97 in Computer Science and Engineering.
• Hands-on experience in modernizing high-stakes trading platforms using React functional components and Material UI, enhancing performance and scalability.
• Proficient in C++, Python, JavaScript, Node.js, and web technologies with expertise in algorithmic trading strategies and risk management, achieving 2500% returns in simulated markets.
• Demonstrated competitive programming excellence with top global ranks in ICPC and Hacker Cup, and advanced problem formulation for AI code generation.

• Senior Java Engineer with 10+ years of experience specializing in Java, Spring Boot, Hibernate, and microservices architecture.
• Proficient in full-stack development using Angular, React, TypeScript, and RxJS, with strong expertise in PostgreSQL, Redis, and cloud platforms (GCP, AWS, Azure).
• Hands-on experience delivering scalable solutions in real estate compliance, ticket management, and corporate social networking domains.
• Skilled in CI/CD pipelines, containerization (Docker, Kubernetes), automated testing (JUnit, TestNG, Mockito), and code quality tools (SonarQube).
• Holds a Bachelor’s degree in Informatics and certifications in Java and Google Cloud.

Led full-stack development of 20+ production applications combining React frontends with AI-powered Python backends. Integrated LLM APIs (Groq, Gemini, Anthropic) into customer projects, building RAG systems and fine-tuned models on local GPUs. Mentored 5+ junior developers. Recently built production React+Flask chatbot with Groq API, deployed on Vercel. Portfolio: https://pro-two-chi.vercel.app/

Backend-focused Full Stack Developer with 1+ year of experience in Node.js, Express.js, TypeScript, and Sequelize ORM. Skilled in building scalable REST APIs, JWT authentication with RBAC, and database optimization using MongoDB and MySQL. Experienced in React.js, Next.js, and Tailwind CSS for frontend development. Proficient in Firebase Cloud Messaging, ExcelJS, Puppeteer, AWS EC2, and Cloudinary. Strong understanding of asynchronous programming, middleware architecture, OOP, and API integration. B.Tech graduate in Information Technology with a passion for developing secure, scalable, and high-performance applications.

• Senior Software Engineer with 5+ years in frontend and full stack development, specializing in Next.js, Angular, and scalable architectures for Web3 and AI-driven platforms.
• Proven expertise in blockchain integrations, real-time systems, and API design, delivering features like automated on-chain actions and wallet-based authentication.
• Strong backend skills with FastAPI, Python, PHP, and database optimization (PostgreSQL, SQLite), improving performance and reducing errors by up to 25%.
• Experienced in mobile app development using Ionic and Cordova, enhancing user engagement and offline functionality for global clients.

• Software Engineer with 1+ years of experience in developing scalable full-stack applications using .NET (C#), React.js, and SQL Server, focusing on responsive UI and efficient backend integration.
• Expertise in AI-driven automation, including LLM-powered applications, Retrieval-Augmented Generation (RAG), prompt engineering, and vector embedding pipelines using Python and AI frameworks like TensorFlow and PyTorch and Exploratory Data Analysis (EDA) to support AI/ML model development and deployment
• Proficient in designing and optimizing REST APIs, database query workflows, and integrating intelligent automation solutions within Agile cross-functional teams.

• 7+ years expertise in Go, specializing in distributed systems, microservices, and legacy system modernization with zero downtime.
• Contributor to open-source projects (KrakenD API Gateway), with published works on distributed teams and mesh networking, demonstrating commitment to software architecture excellence and continuous learning.

• Software engineer with over 7 years of experience specializing in full stack and front-end development.
• Proficient in AngularJS, Sockets, and web/mobile tool development, with a strong background in modern web technologies and frameworks.
• Experienced in Agile methodologies and collaborative team environments across international projects in Spain, the US, Dominican Republic, Argentina, and Venezuela.
• Holds a degree in Informatics from Universidad de Oriente, providing a solid foundation in computer science principles and software development lifecycle.
• Demonstrated ability to maintain and enhance commercial platforms, integrating user feedback and ensuring robust, scalable solutions.

• AI/ML Engineer and Python Developer with 6+ years of experience designing and deploying production-grade AI systems and scalable backend services using FastAPI, PostgreSQL, Redis, and Docker.
• Expertise in Generative AI, LLMs, RAG pipelines, multi-agent systems, and real-time Voice AI, demonstrated by leading complex projects integrating Whisper, ElevenLabs, LangChain, LangGraph, and pgvector.
• Proficient in asynchronous programming with Python asyncio, building custom real-time voice pipelines, and managing multi-phase conversational agents with compliance-critical logic.

• Built LLM and RAG features (prompt engineering, structured JSON outputs, multi-model fallback), including a RAG memory layer for continuous, personalized AI sessions.

• Shipped 8+ full-stack, user-facing features in a 4-month AI platform internship using FastAPI, Next.js, React, and TypeScript.

• Automated tasks and built web scrapers in Python (Selenium, BeautifulSoup, PyAutoGUI) in fintech environments.

• Strong in backend, REST APIs, and cloud (Azure, GCP, Firebase), with CI/CD and Agile.

• Master's in Computer Engineering & Big Data; game projects built in Unity and Unreal Engine 5.

• Software Engineer with 4+ years in secure, scalable enterprise systems using ASP.NET Core, React.js, Node.js, AWS, and Okta identity platforms.
• Expertise in architecting authentication flows, including MFA, SAML integrations, JWT validation, and session management.
• Proven experience in cloud-native solutions, serverless architectures, Terraform automation, and CI/CD pipelines.
• Skilled in troubleshooting production issues, performance optimization, and implementing GenAI-enabled automation tools.
• Bachelor's in Computer Science & Engineering with strong background in IAM, API architecture, and DevOps monitoring tools.