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As a seasoned IT consultant and Solutions Architect, I offer comprehensive guidance to individuals and businesses seeking expertise in the following areas: Solution Architecture: I can provide guidance on designing robust and scalable software solutions tailored to your specific business requirements. Whether you're looking to migrate to the cloud, optimize your existing infrastructure, or build a new application from scratch, I can help you navigate the complexities of solution architecture and ensure the success of your project. Technical Leadership: Drawing from my experience as an Engineering Manager and Technical Lead, I offer guidance on effective team leadership, project management, and collaboration strategies. Whether you're leading a small development team or overseeing a large-scale IT project, I can provide insights and best practices to help you maximize productivity, foster innovation, and drive success. Technology Selection: With expertise in a variety of technologies including .NET, C#, React, Next.Js, Go, and various databases, I can assist you in selecting the right tools and technologies for your project. Whether you're evaluating different programming languages, frameworks, or databases, I can offer unbiased guidance to help you make informed decisions that align with your business goals and technical requirements. Problem-Solving: I excel in solving complex technical challenges and can provide guidance on troubleshooting issues, identifying root causes, and implementing effective solutions. Whether you're facing performance bottlenecks, security vulnerabilities, or integration challenges, I can help you overcome obstacles and achieve your objectives. Questions I Can Answer: What is the best approach for designing a scalable and secure software architecture? How can I effectively lead and motivate my development team to achieve project success? Which technology stack should I use for my project, and how can I ensure compatibility and scalability? What are the key factors to consider when migrating to the cloud, and how can I mitigate risks? How can I optimize the performance of my application and improve user experience? What are the best practices for implementing DevOps principles and automation in my development workflow? How can I ensure data integrity and security in my application architecture? What strategies can I employ to mitigate risks and ensure project delivery on time and within budget?
Currently, David is unavailable for new clients - please watch this space for updates. ========= David has been a software engineer since 1986. He is a full stack web developer with a wide range of experience. He is *very* good at figuring out solutions that stump engineers with less experience. David has been a Web Engineer at 10 Up, where he had the honor of working with a world class WordPress development team. With the release of WordPress 4.5 he is proud to add "WordPress core Contributor" to his list of accomplishments. David has been the chief software architect and CTO of 3B Alliance, an SaaS provider focusing on eCommerce and business to business solutions. In this role he implemented complex payment processing in a distributed environment. David has over 30 years of Software Engineering and IT experience. Involved in internet development since 1994, David has worked as the Director of IT and Software Engineering for an International Insurance Company and the Chief of South Eastern Operations for an International IT Consulting Firm. His professional writing has been published by Sitepoint, DICE, Microsoft, C/C++ User's Journal, PC Techniques and John Wiley & Sons. He has served as an expert witness in Federal court in a software copyright infringement case. He has worked as a consultant for Fortune 500 companies in the manufacturing and financial industries. As an Artificial Intelligence and Physics Simulation Programmer for a major game developer his credits include NFL Full Contact Football, Indy Racing, Jeff Gordon XS Racing and Centipede 3D. Specialties: WordPress, HTML 5, CSS, JavaScript, Web Development, Software Design, Technical Writing, PHP, mySQL, C++, Application Security, eCommerce, API Based Programming, Game Development.
Full Stack Developer for 9 Years Currently Teaching on Codementor Exclusively on Wednesdays and Fridays. Please DM to schedule Full Stack Javascript Developer React + Redux + Node.js. Strapi.io Winner of multiple Ethereum Hackathons (EthGlobal, Gitcoin, AAVE, theGraph, Matic, Polygon, Badger) DeFi Yield Farming Strategy Developer Former Lead Dev at Ethereum Crypto / DeFi Startup Experienced in developing with Solidity, theGraph, Hardhat, Vyper, Brownie. Tons of Wordpress and some Python. Java during CS. Understanding of Bitcoin and Blockchain Technology (course at UNIMIB + experience) Bachelor in CS.
I'm an experienced full-stack developer who has been working as a freelancer for over 10 years now. Right now I'm focused a lot on developing with Elixir, but most of my time I have spent working on projects with PHP. I love creating software that's usable, testable and maintainable. Front-end wise my current framework of choice is VueJS. My projects range from short term projects for smaller customers to bigger and longer projects with bigger companies. My working times are rather flexible, so I don't have a problem working something out that fits me and my clients. I look forward to working with you!
I build the execution, data and backtesting infrastructure that lets a trading strategy run unattended, plus the LLM and agent systems around it, inside your repo, without needing your alpha. Lead developer at a Swiss fintech building automated trading systems. Founder and lead developer of a finance-and-AI software consultancy. Author of a Python open-source project with ~37,000 GitHub stars, featured on the Hacker News front page four times and endorsed by Mr Andrej Karpathy, co-founder of OpenAI. Published the video course "Hands-on Reinforcement Learning with TensorFlow" with Packt. I do not build "guaranteed profit" bots or sell signals. I build the systems that run yours safely, and I will tell you in the first fifteen minutes whether what you have is an infrastructure problem or a strategy problem. What people book me for: - Trading-system architecture and execution-path review: order management, partial fills and all-or-none orders, reconciliation after disconnects, persistent order state, kill switches, paper-trade-first deployment. - Exchange and broker connectivity: WebSocket and REST integrations (Alpaca, CCXT-supported venues, Binance), rate limits, idempotent order submission. - Backtesting infrastructure and the backtest-versus-live gap: fills, slippage and latency assumptions, replay fidelity, parameter search without overfitting. - Market making and liquidity tooling across venues. - LLM and agent systems for finance workflows: orchestration, evaluation pipelines, tool-use design, reinforcement-learning approaches where they actually fit. - Python systems engineering: asyncio, PostgreSQL, FastAPI and Django, production reliability. How a first session usually goes: you share the repository or a design, I ask three questions (budget and timeline; whether you already own the strategy, accounts and data; whether you want infrastructure or "a profitable bot"), and we spend the rest of the hour on the highest-risk part of your system. Longer work continues as a fixed-scope code-review job or an hourly engagement on this platform. Based in Bengaluru (IST), with daily overlap with European hours and the US-East morning. I reply to trading, fintech and AI requests within minutes when online. More at https://satwikkansal.xyz | Consultancy: https://zobyt.com
Software Engineer with 12+ years of experience in web development, backend development, and server architecture. Expertise in building and maintaining various web/backend solutions, from automobile websites to job portals to freelance platforms with live chat integration . Proficient in server architecture setup, deployment, and optimization.
Passionate Android Developer with 7+ years on hand with the Android Framework, Google Developer Expert @ Android & Firebase, Google Associate Android Developer Certification, have made several apps and created delivery app Uh-lala! My mission is to **help you understand the ins and outs of android development** and let you progress in your Android development career. I have been in multiple startups and worked with different apps (fintech, delivery apps, uber apps, and social media apps) which brought to me a broad range of knowledge on these different areas. Currently I'm working as a **Senior Android Engineer** for a big eCommerce app located in LA called ThriveMarket I'm also focused on **backend development** with Firebase which will let you scale your application for large apps and Architecture with MVVM. I have a strong love for **Clean Architecture** and best practices while coding, love to read, and learn every day.
I build the thing end-to-end. Prototype → PRs → deployed system with evals, guardrails, and monitoring. iOS/Swift + Python + agents. You get handover-ready code in your repo, not spaghetti AI. Ex-Uber. 16 years shipping. WHAT I DELIVER: • Production AI systems — not prototypes that break in prod • Evals, guardrails, and monitoring built in from day one • iOS/Swift frontends + Python/agentic backends • Handover-ready code, not spaghetti AI PROOF: • WhisperBoard — 50K+ downloads, 4.8★ rating • mcp-browser-use — 850+ GitHub stars • Ex-Uber engineer, 16 years building production systems • 5.0 rating on Codementor (30 reviews)
Staff Software Engineer with **8+ years of experience building scalable full-stack systems, developer platforms, and fintech integrations**. Currently at **Visa Inc.**, where I architect AI-native developer platforms and developed a **Model Context Protocol (MCP) framework** that enables LLMs to generate production-ready payment integration code while preventing API hallucinations—reducing merchant onboarding time from **30 days to 3 days**. Strong expertise in **Node.js, TypeScript, and Java** for backend systems, along with **React.js** for building developer portals and complex frontend dashboards. Experienced in designing **REST APIs, distributed systems, SDK platforms, and secure payment architectures**. I actively leverage AI coding tools like **ChatGPT and GitHub Copilot** to accelerate development, refactor legacy systems, and improve engineering productivity across full-stack applications.
Full-Stack Web Developer, started coding from 15. A goal-oriented web developer with strong commitment to collaboration and solutions-oriented problem-solving. A self-motivated Web Developer with a high level of experience working on multiple projects. Passionate and hardworking with penchant for meeting deadlines. Interested in roles with companies promoting best practices and offering diverse customer projects. Enjoy process of development, learning new things. Habit of clean,elegant,sophisticated design style to make code maintainable, reusable. Technology Stack: - React.js/Vue.js/Angular.js - MySQL/PostgreSQL/MongoDB/Redis - Node.js/Python/Php - Express/GraphQL/Firebase - Docker/Nginx - Socket.io/REST/WebRTC - Google/Facebook/Twitter/Stripe APIs - Server-Side Configuration(Ubuntu,HTTP->HTTPS) - AWS Services
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The length of a project depends on many factors, including the scope of your project and the technical complexity of it. When you post a freelance Payment systems project request on Codementor, you’ll have the option to indicate when you’d expect the project to be completed. We suggest chatting with the interested developers to ensure both sides are on the same page. For more information on how to post a freelance Payment systems request on Codementor, check out our article.
We don’t charge anything when you post a freelance hiring request for Payment systems developers! You’ll have the chance to determine what the budget for your project is when you post the request. You’ll only need to pay the developer if you’re 100% satisfied with their work. Please know that Codementor charges a small service fee when a developer completes the job.
We do a comprehensive technical and communications screen of all Payment systems developers at Codementor. Our network includes book authors, popular open source contributors, top Stack Overflow users and engineers at top tech companies. In addition, to continually ensure the quality of our freelancers, we regularly check in on existing Payment systems developers’ user satisfaction rates.
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