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Hire the best API Developers in London, ENG

Check out API Developers in London, ENG with the skills you need for your next job.
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  • $150 hourly
    • 4.9/5
    • (44 jobs)
    🥇 Hand picked by Upwork as "Expert-Vetted". This highlights talent that has passed a thorough pre-screening process by experts in their field. These elite freelancers have been evaluated by our Talent Managers for their expertise and excellent soft skills. They represent the Top 1% of talent on Upwork. 🏆 Experienced AI Engineer, CTO & Data Scientist from #1 enterprise software company in the world 🤖 Extensive work with industrial, academic, R&D and start-up scale projects focusing on all aspects of AI Engineering, Data Science and Full Stack Development, such as: 🏢 SAP ➝ #1 enterprise software company in the world. Clients include Greggs, NHS, MindTree, GSK, LSEG, Volvo, Viking and many more... 😇 Halo ➝ Running a global R&D lab focused on delivering tangible results with emerging technology, particularly on human-centric use cases. 🗣️ audico ➝ Built an AI platform for care homes & hospitality including voice, language and generative technologies. As the CTO I architected, implemented and scaled the technology across Europe. 🆙 Upwork ➝ I've built many fruitful long term relationships with clients and pride myself on a 5 ⭐ rating and 100% success rate! My clients range from global corporations to personal projects & startups. The impact that I deliver for clients and where my skillset is most valuable is at the intersection of AI, development and your business objectives. I'm a highly creative technologist that understands the technicalities and complexity of AI, whilst also empathising with the need to deliver value. Whether it's rapidly developing an MVP, optimising an existing AI pipeline or building and deploying a production ready AI system within your existing stack, I would love to help you on that journey using a tried and tested, proven framework that I've used for over 10 years. I'm happiest when I'm working with innovative clients on inspiring projects, building something to make our society a better place! What can we build together? The sky is the limit... ❓WHAT MAKES ME DIFFERENT? 💡 Creativity ➝ A skill that is commonly overlooked in the technical space. Despite my technical education & experience, my passion lies in creativity. I have a keen eye for design and I love creating tangible solutions, services & products. Anything we create together will be bespoke to your exact needs. 🗣 Communication ➝ 90% of AI projects never make it to production, I've seen this first hand. A large contributor to this is ineffective communication and alignment with business value & objectives. I have over 10 years of experience with stakeholders at all levels communicating complex AI projects and selling these concepts into businesses. Hence, communication plays a huge part in my value proposition. I'm a clear & confident communicator with vast experience in public speaking, enablement & onboarding. I was recognised as a “Gifted Public Speaker” at SAP and was Head of Enablement for Machine Learning across EMEA, designing and delivering technical training to over 200 consultants. 🤝 Trust ➝ From running my own businesses I know how hard it is to find people to trust. I'm a friendly, open & approachable person that strives to build rapport with you straight from the start. I value long lasting relationships where we can build incredible technology together! I would love to hear about your business & what you're working on, please reach out! You can rely on me to respond in an honest, timely & advisory manner always 👍🏽
    Featured Skill API Development
    Mathematical Modeling
    Curriculum Development
    Artificial Intelligence
    Virtual Reality
    Digital Signal Processing
    App Development
    Cloud Development
    API Integration
    JavaScript
    Python
    Web Development
    Data Science Consultation
    Data Science
    Machine Learning
    LLM Prompt Engineering
    AI Agent Development
    AI Model Development
    AI App Development
  • $55 hourly
    • 4.7/5
    • (50 jobs)
    With over Eight (8) years of experience as a Full Stack Software Engineer, I thrive on challenges and actively seek projects that push me beyond my current comfort zone, fostering continuous learning and growth. My diverse skill set contributes to the success of organisations, covering the entire life cycle of development. Frontend Technologies and Frameworks: React.js, Next.js, Vue, Nuxt, Javascript, Typescript, Apollo, HTML5, CSS3, Bootstrap, Tailwind CSS, LESS/SASS Material UI, Ant Design Backend Technologies and Frameworks: Node.js, Nestjs, GraphQL, Python Mobile Development: React Native Databases: MongoDB, PostgreSQL, MySQL, Firebase Other Skills: Web scrapping, Web Crawling, Web Automation, Data Extraction, Database Engineering, Product Design and Development; API Development , security and integration. I am eager to discuss how my extensive skills and experience align with the needs of your ongoing projects. I am confident in my ability to make significant contributions. Looking forward to the opportunity! Cheers!
    Featured Skill API Development
    React Native
    Automated Workflow
    NestJS
    Node.js
    Next.js
    React
    TypeScript
    JavaScript
    API Integration
    Mobile App Design
    Mobile App Development
    Software Architecture & Design
    Software Development
  • $20 hourly
    • 5.0/5
    • (7 jobs)
    Full Stack Developer (FLutter, PHP, Angular) With 15+ years of experience in development and business analysis, I have worked across various sectors and international clients to bring their business ideas to reality. My core expertise Flutter, Python. Working frontend and backend for Mobile Applications. Cloud resource deployment including GCP, Azure, CI and CD, Jenkins, GIT Node JS, Python, Flutter, Swift, Kotlin, Laravel, Codeigniter, PHP I always satisfy clients with high end results. Thanks,
    Featured Skill API Development
    Android
    Laravel
    Java
    Hybrid App Development
    Flutter
    Mobile App Development
    CRM Development
    PHP
    Kotlin
    Swift
    WordPress
  • $70 hourly
    • 5.0/5
    • (44 jobs)
    👋 Hello! I'm a seasoned Senior Software Engineer with over 10 years of experience in the industry. I'm passionate about developing high-quality software that meets the needs of my clients and end-users. 💻 My technical expertise includes proficiency in PHP, C# Java, Python, and JavaScript (and TypeScript), as well as experience with agile development methodologies, cloud computing, and DevOps practices. I'm always learning and staying up-to-date with the latest technologies to ensure that I can deliver the best possible solutions for my clients. 👨‍💼 As a team player and effective communicator, I've collaborated with cross-functional teams to develop and implement software solutions that have helped companies achieve their business goals. I'm also an independent problem-solver who can work autonomously to deliver results. 🏆 I'm committed to delivering high-quality work that exceeds my clients' expectations. My hourly rate is $70, but my goal is to provide value that far exceeds that investment. I'm confident that I can help you with your software development needs and look forward to working with you!
    Featured Skill API Development
    Stripe
    Bot Development
    Web Development
    Node.js
    JavaScript
    NGINX
    Python
    Phalcon
    ASP.NET Core
    Docker
    C#
    .NET Framework
    Laravel
    PHP
  • $40 hourly
    • 4.8/5
    • (48 jobs)
    🌟 14+ Years Of Experience 🌟 Top PHP, Laravel, Node.js, React.js, Next.js and APIs development on Upwork. ✅ Senior Full Stack Developer ✅ Senior APIs Expert 🏆 500+ Upwork hours I have been in this industry for 14+ years and have been providing my services of full stack development locally and globally. I have a strong understanding of front-end and back-end development. Skills: I have command on variety of programming languages and frameworks, including PHP, Laravel, React.js, Next.js, Node.js, etc. I am experienced in working with a variety of project management tools and methodologies. I handle Full-Stack development-From scratch to complete product. I have great suit in third-party API development and integrations.
    Featured Skill API Development
    Full-Stack Development
    REST API
    Web Development
    SaaS Development
    Stripe API
    Web Application
    React
    API Integration
    MySQL
    JavaScript
    Laravel
    Node.js
    PHP
  • $50 hourly
    • 4.6/5
    • (9 jobs)
    I am a very experienced python developer with 6+ years of experience with it as well as a host of full-stack projects in my portfolio. I am proficient with the React, Django, Flask, Tailwind CSS and React-Native frameworks as well as HTML and JavaScript languages. My skills are wide in range and can be applied to many abstract and niche tasks that have specific requirements and require attention to detail and meticulousness.
    Featured Skill API Development
    Progressive Web App
    Django Stack
    Software Design
    Front-End Development
    Back-End Development
    React
    Data Scraping
    Automation
    Python
  • $120 hourly
    • 5.0/5
    • (14 jobs)
    Passionate about delivering real value to real people. Expert at developing high-quality software solutions that leverage appropriate automation techniques.
    Featured Skill API Development
    Back-End Development
    IT Career Coaching
    REST API
    API Framework
    Domain-Driven Design
    Clean Architecture
    Spring Boot
    Scala
    Java
    API Integration
    Kotlin
    DevOps
    Kubernetes
    Agile Software Development
  • $40 hourly
    • 4.9/5
    • (7 jobs)
    As a Data Scientist with my MSc from Durham University, I bring a thoughtful approach to machine learning and predictive analytics challenges. My work combines technical expertise with a keen understanding of business objectives, ensuring data solutions deliver genuine impact. I've had the privilege of helping clients transform their operations through customized applications and data pipelines. Whether implementing time series analysis to forecast revenue patterns or building NLP systems that capture the voice of customers, I focus on creating solutions that provide clear strategic value. What sets my work apart is the integration of data science methodology with strong engineering practices. This has allowed me to develop systems that not only provide insights but operate efficiently in production environments—like the financial analysis pipeline I built that reduced processing time from hours to minutes. My background spans cloud platforms (AWS, Azure, GCP) and includes both freelance consulting and technical leadership roles. I'm passionate about translating complex technical concepts into clear business language, making data accessible to stakeholders at all levels. I approach each project as a true partnership, committed to understanding your unique challenges and delivering solutions that exceed expectations.
    Featured Skill API Development
    ETL Pipeline
    dbt
    Apache Spark
    Apache Kafka
    Google Cloud Platform
    Data Engineering
    Azure DevOps
    Tableau
    Microsoft Power BI
    Data Analysis
    Data Science
    Application
    C#
    Python
  • $350 hourly
    • 5.0/5
    • (2 jobs)
    👨🏻‍💻 Product Executive and Entrepreneur. Building my next venture, helping start-ups 🚀 ➣ Founder and CPO at Advanon. Built a novel credit algorithm that funded over 400m EUR to 1k+ businesses ➣ Product Lead at Revolut. Designed and built the Super App experience that attracted 500k+ businesses ➣ EVP of Product at Uncapped. Built the next generation of banking and funding ➣ Background in Engineering & Management from ETH Zürich & TU Delft ➣ Gained Engineering and Product Management experience at numerous start-ups and corporates such as ING, DNB and Google
    Featured Skill API Development
    API
    App Development
    Data Analytics
    Product Development
    App Design
    SaaS
    Web Design
    Web Development
  • $95 hourly
    • 5.0/5
    • (13 jobs)
    Dynamic, strategic, and entrepreneurial Director with a stellar record of spurring revenue growth and delighting customers by selling the vision, fostering lasting relationships, pinpointing customers' needs, opening doors to key decision-makers, negotiating and closing strategic accounts for large and startup businesses. Astute in leading high-strategic business plans and developing value-driven services and business solutions that boost annual revenues. Keen ability to gauge target markets and forecast trends to source and integrate new sales and marketing opportunities with the company's goals.
    Featured Skill API Development
    CRM Development
    CRM Automation
    LinkedIn Lead Generation
    LinkedIn Marketing
    Marketing API Integration
    Automation
    API Integration
    Business Development
    Outbound Sales
    Email Deliverability
    Cold Email
    Email Copywriting
    Email Automation
    Marketing Automation
  • $37 hourly
    • 5.0/5
    • (1 job)
    Hi, I’m Leon 👋 I led AI automation teams at Deloitte ($67.2B rev) & Atos ($2.31B rev). Today I help businesses automate and optimize operational and sales systems. I've saved a UK hospital $240,000 per year, added $6,200 MRR to a marketing agency in just 27 days, and generated $103,000 in 3 months for an eCommerce brand—without paid ads. I design and implement automation systems that improve operational efficiency, drive revenue, and reduce manual work across a wide range of industries. My work spans intelligent scheduling systems, AI-powered lead generation, content workflows, CRM automation, and cross-platform integrations tailored to each business’s needs. Typical projects include: – Hyper-personalised cold outreach systems that generate and send tailored messages using AI and dynamic data – CRM pipeline automations that move deals, update statuses, tag contacts, and trigger next steps automatically – Ecommerce workflows that sync orders, customers, and inventory between platforms like Shopify, WooCommerce, Google Sheets, and fulfilment services – Scheduling automations that manage calendar bookings, send reminders, follow-ups, and dynamically handle reschedules – Onboarding sequences that handle client intake, payment forms, document collection, and internal task setup – Content automation systems that publish blogs, newsletters, and social content on a schedule, with AI-generated drafts – Dashboard and reporting flows that consolidate data from multiple tools into Airtable, Google Sheets, or Power BI for real-time insights – Cross-platform sync automations (e.g. ClickUp ↔ Notion, Trello ↔ Slack, HubSpot ↔ Google Sheets) to keep teams and data aligned without manual effort I work across a broad stack of platforms and tools, including: Automation & AI – Make (Integromat), Zapier, n8n, GPT-4, ChatGPT, Claude, Pabbly CRM Systems – HubSpot, Salesforce, ActiveCampaign, GoHighLevel, Pipedrive, Zoho Project & Ops – Airtable, Trello, Notion, ClickUp, Monday.com Ecommerce & Marketing – Shopify, WooCommerce, Webflow, Klaviyo, Mailchimp Scheduling & Communication – Calendly, Twilio, Gmail, Slack, WhatsApp, Outlook Analytics & Reporting – Power BI, Google Sheets, Data Studio, Airtable Interfaces Whether you're looking to automate operations, streamline your sales funnel, or connect disjointed tools into a cohesive system, I bring a practical, results-driven approach grounded in enterprise experience and real-world ROI.
    Featured Skill API Development
    LLM Prompt Engineering
    Business Intelligence
    HubSpot
    Shopify
    Lead Generation
    Marketing Automation
    Email Automation
    CRM Automation
    Airtable
    GPT-4o
    AI Consulting
    Automation
    Zapier
    Make.com
  • $40 hourly
    • 5.0/5
    • (2 jobs)
    💼 Professional Summary I'm a seasoned Full Stack Developer with 6+ years of experience crafting robust, scalable web solutions across diverse business environments. From secure content platforms to educational tech products and dynamic applications, I deliver comprehensive technical solutions that drive business success. 🛠️ Technical Expertise 🔄 Full Stack Mastery: End-to-end development with seamless frontend-backend integration 📚 MERN Specialist: MongoDB, Express.js, React.js, Node.js implementation and optimization ☁️ AWS Cloud Services: Lambda, API Gateway, DynamoDB, S3, CloudFront, IAM 🏗️ Architecture Design: Serverless, Microservices, Event-driven systems 🖥️ Frontend Development: React.js, Redux, Material UI, Responsive Design ⚙️ Backend Engineering: Node.js, GraphQL, REST APIs, Authentication systems 🔄 DevOps Integration: CI/CD pipelines, Docker, Kubernetes, Automated testing 📊 Database Management: Schema design, Query optimization, Data modeling ✨ What Sets Me Apart 🔹 End-to-End Delivery: Complete project management from concept to deployment 🔹 Performance Optimization: Solutions that enhance speed, efficiency, and user experience 🔹 Cost-Effective Architecture: Smart designs that minimize operational expenses 🔹 Collaborative Approach: Transparent communication and inclusive decision-making 🔹 Technical Excellence: Adherence to best practices and modern development standards 🏆 Notable Achievements 📈 Engineered serverless GraphQL backend for EdTech platform → 200% user base growth 🚀 Led backend optimization at CodeJunkie → 25% system performance improvement 🔌 Developed Chrome extension at NICKLPass → 40% increase in user access 💻 Architected AWS cloud solutions → 35% reduction in infrastructure costs 🔄 Implemented CI/CD pipelines → 70% faster deployment cycles 🤝 Working Philosophy I thrive in collaborative environments where technical excellence and innovation drive success. My approach combines strong technical expertise with clear communication and adaptability, ensuring your project succeeds regardless of complexity or scale. Looking for a developer who can transform your vision into reality? Let's connect and discuss how my comprehensive skill set can elevate your next project.
    Featured Skill API Development
    Redux
    TypeScript
    GraphQL
    Amazon DynamoDB
    Sequelize
    PostgreSQL
    Database Design
    SQL
    Google Chrome Extension
    Serverless Stack
    Node.js
    React
    Amazon Web Services
    JavaScript
  • $49 hourly
    • 4.9/5
    • (59 jobs)
    Need an expert developer or consultant to develop API end points and integrate your heterogeneous platforms on the right foot with large scaled, standard and secured way? I've worked with over 50 USA/UK/Canada/Australia based companies in planning, designing and developing APIs for heterogeneous platforms in a way that fits your business. Whether it's customizing existing API or web application with features that align with your business processes and goals or recommending third-party API/apps to help bridge that gap, I have a true passion for delivering the right mix! Beside API developer, I'm certified web and enterprise application developer for last 10 years which greatly help me to face challenges and provide efficient solutions on complex business requirement. Keeping your business data secured and confidential is my first priority. List of certificates from international vendors: - PHP Certified Developer (zend.com/en/yellow-pages/ZEND011275) - Java Core Developer ( Certified by ORACLE) - Java EJB Developer Expert ( Certified by ORACLE) - Java Web Service Developer Expert ( Certified by ORACLE)
    Featured Skill API Development
    Custom PHP
    PHP Script
    Laravel
    CakePHP
    Node.js
    PHP
  • $40 hourly
    • 4.9/5
    • (9 jobs)
    With 14+ years of expertise, I specialize in Salesforce implementation & customization, AI-driven solutions, and full-stack development. As the Head of WTT Solutions and a Salesforce Consulting Partner at Innovadel Technologies, I lead teams delivering cutting-edge web, mobile, AI, and CRM solutions for startups to Fortune 500 companies. 🔹 Salesforce Solutions – Sales, Service, Marketing, Experience, Health & Commerce Cloud, AppExchange Development, CRM Migrations, API Integrations (Stripe, Mailchimp, DocuSign, etc.), and Solution Architecture. 🔹 Full-Stack & AI Development – MERN, PHP Laravel, Node.js, ASP.Net, Python (AI-focused), React Native, AI/ML (OpenAI, ChatGPT, Object Detection). 🔹 Cloud & Databases – AWS, MongoDB, PostgreSQL, MSSQL, MySQL. 🔹 Core Services – SaaS Development, AI Integration, MVP Building, Technical Consulting, and Scalable System Architecture. Trusted by industry leaders like Turner Broadcasting, Movado, Superdrug, Experian, and Cloudinary, I deliver high-impact, scalable technology solutions that drive business growth. Let's build something innovative together! 🚀
    Featured Skill API Development
    Web Application
    Mobile App
    Salesforce App Development
    Apex
    Salesforce Marketing Cloud
    Salesforce
    Demandware
    Salesforce CRM
    Salesforce Sales Cloud
    Salesforce Service Cloud
    Ecommerce Website Development
    Salesforce Lightning
    JavaScript
  • $45 hourly
    • 5.0/5
    • (12 jobs)
    **Trying to get fresh activity on this old account - Offering discounted rates for the first few projects I log on Upwork** Feel free to look me up on LinkedIn and see my work experience. I'm co-founder of a services agency specialised in marketplace management. I have 10 years of case studies available, and plenty of happy client references. - Grew Le Mieux on Amazon from 0 to 1 million in 9 months. - Took WhiteStuff to 400% growth on eBay in 12 months. - Boosted WooWoo sales by 500% domestically and 1,900% internationally. - Nisbets conversion rates up 190% Amazon Stats (average in first 9 months): - 208% Sales increases - 213% Conversion increases - 54% Buy box ownership increases eBay I grow on average by 259% in the first year. I run roughly 150 other channels in the UK, USA and EU. I make Marketplace Store Management easy, affordable, scalable and efficient so you don't have to. The key is automating the daily routines and streamlining process through technology, so opportunities and growth is the main focus. If you lack the technology, don't worry, I can bring that with me. In 2024, focusing on Brand marketing management, Marketplace advertising and analytics is critical. Reporting on how things are going, and where the opportunities are, in monthly / weekly check in's ensures we are always testing theories and pursuing possibilities. Data is key to everything, so its important we have the metrics and insights ready made for examination. Expertise in: - eBay - Amazon Seller and Vendor - Amazon PPC Management - Etsy - Onbuy - Cdiscount - Zalando - Debenhams - Trademe - Tesco (Beta Launches) - ASOS - BnQ - Google Shopping - ... and many other channels. Experts with: - ChannelAdvisor (Now Rithum) - Linnworks - ChannelEngine - Sellbrite - Skucloud - eSellerpro (Now Volo) - Shopping Feed - Netsuite - ... and many more providers. I can run, launch or help you transition marketplace operations. Or, just coach your team with advice and methodologies. I also have a robust time tracking reporting custom suite you can license independently if you want to better police and report on your existing team's work and time. I work with brands and sole traders alike. From Disney (3 year on Amazon UK/EU) to small start ups, to mid range physical store owners like Mountain Warehouse (7th year), to successful online retailers like Charles Bentley (6th year), I forge long lasting partnerships.
    Featured Skill API Development
    Business Operations
    On-Page SEO
    eBay API
    Facebook Marketplace
    Amazon PPC
    Ecommerce Website Development
    Amazon Listing Optimization
    Strategic Plan
    Amazon Web Services
    Product Research
    Magento
    Graphic Design
  • $75 hourly
    • 5.0/5
    • (48 jobs)
    🔸 Top 1% in Upwork. 🔸 100% Job Success. 🔸 2,700+ hours. 🔸25+ years experience. I deliver high-quality, engineered software that is robust, works at scale, and can grow as fast as your business grows. ❝ High-quality software is not complicated - it just requires discipline and steadfast attention to detail on each step of the journey. ❞ What's stopping you from starting your journey to software excellence and fixing your business' pains? You can arrange a call with me to discuss your project needs for free in a 30-minute consultation call! Hi. I'm Jason - an experienced (25+ years) software architect and engineering professional involved in all parts of the SDLC (Waterfall, Agile and Hybrid methodologies). With a wealth of experience across industries such as commercial aviation, banking (real-time payments processing & FX), 24/7/365 manufacturing lines, e-commerce, and public transport (smart card), I will bring a passion for delivering elegant and reliable solutions to your project. I will work with you (and your team) to provide the best possible technical solution to your business problem. No matter the business domain or challenges you are facing, l have deep technical and architectural knowledge, as well as excellent communication skills, to help solve your business problem with the right software solution. I will bring to bear a highly focused set of technical and people skills to help your project succeed. The recommendations and advice I provide focus on minimizing risks and maximizing your project's chances of success. This is what my 25+ years of experience bring you: honest, robust, and intelligent solutions to see you succeed. When asked to build software, I deliver high-quality server-side C# .NET software solutions that give what you need: Software engineered to be robust, scalable, and designed to exceed your business expectations. What you'll get when you choose me to work with you: ⭐️ Clear, effective communication ⭐️ Precise, quality recommendations to ensure success for your project ⭐️ A focused, collaborative approach to work with you and your team ⭐️ A no-nonsense, results-focused approach that delivers value to your project For example, this are what a couple of my clients had to say: ❝Jason is by far the best architect I have ever worked with. He displays extreme ownership of his work and it's incredibly refined. Every deliverable was on time or ahead of time. Not only did Jason provide an incredibly performant and scalable architecture, the documentation he provided was top notch. I will forever keep Jason and my goto for any and all technical and solution architectural needs.❞ Cade - VP Engineering - US Software Company ❝Jason helped get our team on our feet for doing proper documentation and much more, actually. He helped improve the engagement of our team members and how they work together. If we can, we will surely ask for his help again in the future. I can only give high praise of Jason's quality of work. We highly recommended for documentation and general architectural design work.❞ Alexander L - Acting CTO - Global On Media If you are interested in working together, please invite me to your job on Upwork. I look forward to hearing from you soon and helping you deliver on your software vision. Regards, Jason. A highlight of my technical specialties I can help you with: ✅ .NET Technical and Solution architecture consultancy and design ✅ C#.NET ✅ Team leading, technical .NET mentoring, and coaching ✅ High availability solution designs (24/7/365) ✅ Event-driven architectures (including actor-based systems) ✅ Highly concurrent software design (thread-safe) ✅ High volume, low latency software designs ✅ Cloud (MS Azure and AWS) solutions ✅ Hybrid (on-premise and Cloud) solutions ✅ Microservices ✅ Message brokers and ESB ✅ SOLID, DDD, OOP, and TDD ✅ Experienced in Agile and Hybrid delivery models ✅ Container (Docker) deployments software using CI/CD (Azure Devops) ✅ Dependency Injection (DI using Autofac, DryIoc) A highlight of the software products I'm experienced with: ✅ Sparx Enterprise Architect ✅ JetBrains Rider IDE ✅ Confluence, JIRA ✅ Git ✅ Resharper, DotMemory, DotTrace ✅ VMWare (Fusion) ✅ Visual Studio 2019 IDE Other clients had this to say about my work with them: ❝Jason was a tremendous professional, outstanding architectural skills and understanding both technical and business requirements.❞ Brian V - COO - LaunchControl
    Featured Skill API Development
    Requirements Specification
    Multithreaded Programming
    Microservice
    C#
    .NET Core
    Cloud Computing
    Software Architecture & Design
    Enterprise Architecture
    TOGAF
    Enterprise Software Development
    Software Consultation
    Solution Architecture Consultation
    Solution Architecture
    Akka.NET
  • $65 hourly
    • 4.9/5
    • (58 jobs)
    Hi! I’m a Full-Stack Developer and Consultant who helps businesses grow with custom web applications, high-converting e-commerce stores, and results-driven marketing sites. As an Upwork Expert-Vetted professional (top 1%), I've maintained a 100% success rate across 50+ projects by focusing on what truly impacts your business: revenue and operational efficiency. I excel at managing projects end-to-end, from gathering requirements through to design and development. I have experience with large team projects with 20+ people and small-team initiatives. I can deliver resourceful solutions that align with your business goals and budget. My tech stack includes: Languages: PHP, JavaScript, Python Frameworks: Laravel, Vue.js, Nuxt.js E-commerce: Shopify, WooCommerce CMS: Statamic, WordPress Hosting & Cloud: AWS, DigitalOcean If you’re looking for a partner to handle your tech so you can focus on serving your customers, let’s discuss your project in detail. How about we schedule a call?
    Featured Skill API Development
    WordPress e-Commerce
    Product Design
    Front-End Development
    Marketing
    Marketing Audit
    Amazon Web Services
    API
    WordPress
    JavaScript
    Theme Development
    PHP
    Website Optimization
    HTML5
    Landing Page
    CSS
  • $27 hourly
    • 5.0/5
    • (3 jobs)
    Hi! My extensive experience includes 3D modelling/texturing/rendering/ray-tracing and proficiency in WebGL library Three.js. I create interactive and visually stunning 3D graphics directly in the browser. I am also well-versed in react-three-fiber, a React renderer for Three.js, blender, babylonjs, WebGPU and WebGL which enables me to efficiently build dynamic and responsive 3D web applications. I can create web application using ReactJS, Python, and .Net. With 4 years of experience in web technologies i can use Django, MongoDB, Postgres, Node/Express, and AWS technologies for optimized and stunning web applications. I can create CRMs, CMS, Profile, Service Based, IoT based web applications. I can work on Native technologies to create IoT, Ecom, Service based, AR/VR/XR, 3D, and specialised applications for disabled users. I can work on Flutter, React Native, Java, Kotlin, Swift and C#. Why me? ⭐️ Communication guaranteed. Explain application's idea, I will create road map and designs and will follow agile methodology ⭐️ I've been working in this AR/VR and 3D web development field for 4 years. ⭐️ I come from a Design background and I am a creative developer ⭐️ Strong 3D mathematical/MatLab skills ⭐️ Strong Mobile Application Development Skills Key skills I bring to the table? 👉 Three.js 👉 React-Three-Fiber 👉 React 👉 D3 👉 MUI 👉 GreenSock/GSAP 👉 Tween.JS 👉 3D Mesh Design using Blender & Maya 👉 PBR shaders, OpenCL Shaders, SSAO Shaders and Phong Shaders 👉 Graphics Pipeline Optimization 👉 Node.js/ Express 👉 MongoDB 👉 Relational Databases/ No-SQL 👉 Django 👉 Lead Generations/ Email Marketing 👉 OpenAI APIs, Chatbots, ChatBoxes, and custom Neural Network Models My commitment to staying at the forefront of 3D web development trends drives me to explore new tools and techniques continuously. With adaptability and enthusiasm, I am always ready to take on new challenges. Let's connect if you are looking for a skilled 3D web developer who can transform your vision into innovative and captivating 3D web experiences. Together, we can create something extraordinary that sets your brand apart and engages your audience like never before! You can find my portfolio below for some examples of my three.js pages. Feel free to contact me for any inquiries as well
    Featured Skill API Development
    API Integration
    React Native
    React
    Three.js
    ARCore
    JUnit
    Selenium
    Spring Boot
    API Testing
    Android App Development
    Hibernate
    JavaFX
    Database Integration
    OpenGL
    Microsoft SQL Server
  • $25 hourly
    • 5.0/5
    • (3 jobs)
    ✅ Experienced Full Stack Developer Ready to Elevate Your Projects ✅ 6+ years of experience ✅ 100+ projects delivered ✅Level 2 saller of Fiverr Hello there! I'm Ahsan, a seasoned Full Stack Developer with over 6+ years of hands-on experience in MEAN/MARN stack development. Whether you're looking to build a robust web application or enhance an existing one, I've got you covered. Here's what I bring to the table: ✅Expertise in Responsive HTML/CSS coding, including HTML5/CSS3, SASS/LESS/SCSS, and frameworks like Bootstrap/Material Design. ✅Proficiency in front-end technologies such as React, Next.js, Angular, and Vanilla JavaScript, with legacy support for jQuery. ✅Strong backend development skills using Node.js (ExpressJS, NestJS, etc.), with a focus on Test-Driven Development (TDD) and Swagger documentation. ✅Extensive experience working with databases and data stores, including MySQL, PostgreSQL, MongoDB, Redis, and MSSQL. ✅Familiarity with various web hosting platforms like Digital Ocean, Heroku, AWS, and Hetzner, along with CDN setups using Cloudflare, AWS S3, and Canaray. ✅Knowledge of other technologies such as WebSockets, Nginx, RabbitMQ, MailChimp, Paypal Integration, FCM Notifications, TypeORM, Sequelize, Mongoose, PWA, Offline SPA, and more. ✅Proficient in QA and test automation techniques, including Checklists, Test Cases, Test Plans, and Automated Testing with TDD. ✅Skilled in UX/UI development, including Wireframes, Branding, Mockups, Color Schemes, and Style Guides. ✅Expertise in optimizing page performance and load speed, utilizing tools like Google Page Speed Insights. Since 2016, I've been dedicated to delivering high-quality web solutions from inception to completion, consistently meeting deadlines and exceeding client expectations. Now, I'm excited to bring my expertise to your project and help you achieve your goals. Whether you need assistance with CMS implementation, CRM management, or streamlining your business processes, I'm here to help. Let's connect today to discuss how we can collaborate effectively. ✅Looking forward to working together!
    Featured Skill API Development
    NestJS
    CSS
    CSS 3
    HTML5
    RESTful Architecture
    PostgreSQL
    Web Application
    MongoDB
    MySQL
    ExpressJS
    Node.js
    Angular
    Next.js
    React
  • $25 hourly
    • 5.0/5
    • (3 jobs)
    🔝TOP RATED PLUS SELLER 🏆100% Job Success 🏆Top 1% Freelancer Looking for a Full Stack Developer who can build fast, scalable, and modern web apps from the scratch? You’ve landed on the right profile. I’m a highly experienced Full Stack Developer with over 6 years of hands-on experience building complete web applications using the MERN stack, React.js, Next.js, Vue.js, Node.js, NestJS, PHP, Python, and TypeScript. From frontend UI/UX to backend APIs and database architecture, I build clean, responsive, and secure applications tailored to your business goals. Whether you're launching a startup, scaling an existing product, or modernizing legacy code, I’m here to deliver end-to-end solutions that perform and scale. ✅ What I Specialize In: 🚀 Frontend Development: 🔹React.js development – reusable components, hooks, responsive layouts 🔹Next.js development – server-side rendering, static site generation, SEO optimization 🔹Vue.js development – lightweight interfaces, clean state management 🔹TypeScript – type-safe, scalable frontend code 🔹Tailwind CSS / Bootstrap – responsive, mobile-first design 🛠️ Backend Development: 🔹Node.js development – fast, event-driven backend services 🔹NestJS development – modular, scalable backend architecture 🔹Next.js API routes – serverless backend with frontend integration 🔹PHP backend – custom APIs, CMS integration, legacy app support 🔹Python backend – scripting, automation, and lightweight APIs 🔹TypeScript – backend structure with type safety and maintainability 🔹Database integration – MongoDB, PostgreSQL, MySQL 🔹Authentication & Security – JWT, OAuth, session handling 🔍 Why Hire Me: ✅ Full stack expertise from UI to server logic ✅ SEO-optimized, fast-loading apps with React.js, Next.js, and Node.js ✅ Proven track record with the MERN stack and modern frameworks ✅ Clean, maintainable, scalable code ✅ Great communication, clear timelines, and reliable delivery If you're looking for a full stack developer with real experience in React.js, Next.js, Vue.js, Node.js, NestJS, PHP, Python, and TypeScript, let’s connect. 📩 Send me a message and let’s build something amazing together.
    Featured Skill API Development
    Python
    PHP
    Vue.js
    AWS Lambda
    NestJS
    Next.js
    Node.js
    React
    API Integration
    Back-End Development
    Front-End Development
    Web Application
    Web Development
    Full-Stack Development
  • $30 hourly
    • 5.0/5
    • (2 jobs)
    Flutter🚀, Dart🎯, Cross-Platform Development🌍, UI/UX Design🎨, API Integration🔌, PHP🐘, Laravel⚔, Ionic📱, AngularJS🅰️, Yii🖥️, Joomla!📚, WordPress📝, OpenCart🛒, Moodle🎓, Yii APIs🔧, CodeIgniter🛠️, Amazon S3☁️, Google APIs🔍, CSS💅, SCSS🎨, Less🖌️ Hi, I’m a full-stack developer from the UK, passionate about transforming your web and mobile visions into reality. Boasting 5 years of experience with PHP and Laravel, I specialize in creating exceptional plugins, themes, and custom features that uplift your projects. Over my career starting in 2017, I’ve successfully delivered thousands of websites, online stores, and eye-catching landing pages that boost user engagement. My dedication to quality and affordability ensures your projects exceed expectations without exceeding your budget. I pride myself on excellent communication and punctuality, always available through Skype or Gmail for any queries or updates. Let’s collaborate to make your ideas stand out in the digital landscape! 🚀Flutter: Expertise in leveraging Flutter to create seamless, high-performance mobile apps for both Android and iOS platforms. 🎯Dart: Skilled in utilizing Dart programming language to develop maintainable and efficiently functioning applications. 🌍 Cross-Platform Development: Proficient in creating apps that provide consistent and high-quality user experiences across multiple platforms. 🎨UI/UX Design: Passionate about designing intuitive and visually appealing user interfaces that enhance usability and user engagement. 🔌API Integration: Experienced in connecting applications with various APIs and backend services to enhance functionality and user experience. And so on for each skill listed in the initial skill set, providing clarity on what each entails. Let’s work together to turn your vision into a reality. Reach out now! Skills 1. Full-Stack Developer: Flutter, Laravel, UI/UX, API Integration Expert 2. Flutter & Dart Specialist | Cross-Platform App Developer 3. PHP & Laravel Developer | Custom Web Solutions Expert 4. UI/UX Designer & Full-Stack Developer | Tech Innovator 5. Web & Mobile App Developer | Flutter, UI/UX, PHP, Laravel Pro
    Featured Skill API Development
    Drupal
    WordPress
    Vue.js
    .NET Core
    WooCommerce
    Laravel
    AngularJS
    JavaScript
    Ionic Framework
    Android App Development
    iOS Development
    React Native
    PHP
  • $28 hourly
    • 5.0/5
    • (2 jobs)
    A highly resourceful, innovative, and competent PHP , Laravel , Wordpress, Node, React, NextJS, AI, Angular developer with extensive experience in the layout, design, and coding of websites. Possessing considerable knowledge of the development of web and mobile applications. Experienced in developing applications and solutions for a wide range of corporate, charity and public sector clients and having the enthusiasm and ambition to complete projects to the highest standard. Looking for a suitable developer position with an ambitious & exciting company. * 7 years of professional experience as a software engineer * Excellent knowledge of relational databases * Experience in common third-party APIs * Good in managing time and organizing tasks * Quick learner and ability to learn new concepts and technologies * Career oriented, hard-working and ability to handle multiple tasks Looking forward to work with you. cheers
    Featured Skill API Development
    CSS
    AJAX
    Node.js
    Next.js
    React
    MySQL
    HTML
    CodeIgniter
    Shopify
    WordPress
    jQuery
    API
    Laravel
    SQL
    PHP
    JavaScript
  • $25 hourly
    • 5.0/5
    • (3 jobs)
    I'm a quantitative financial analyst and algorithmic trading data scientist with over 15 years of professional experience in technical and trading roles at hedge funds and major trading companies. I'm an expert at all aspects of systematic trading, going from raw idea, to fully automated systematic trading strategy. Strategy design & signal development Whether you arrive with a rough sketch or a fully-formed hypothesis, I help translate it into clear rule sets or statistical signals. Robust back-testing I build event-driven test environments that respect market microstructure: realistic fills, spreads, latency, and transaction costs. Applied machine learning (when it adds value) Some problems benefit from additional pattern-detection—regime classification, order-flow imbalance, or adaptive position sizing. Where appropriate, I incorporate ML techniques, but only when they improve risk-return relative to simpler rules. Deployment & oversight Strategies can be delivered as semi-automated tools (you review signals, click to trade) or fully automated pipelines posting orders to Interactive Brokers, Alpaca, or exchange APIs. Independent model review Funds often retain me for a “second opinion” on in-house or vendor models before capital is committed. I examine code, data-handling, leakage risk, and performance attribution, then provide a concise report highlighting strengths, weaknesses, and remedial steps. Expert witness & litigation support I assist in cases involving algorithmic trading, model risk, or market abuse—providing clear technical analysis and expert testimony. --- I'm very laid back about how engagements begin, and I appreciate that clients are keen to have conversations with multiple freelancers before choosing one. I'm happy to have a call and chat through your ideas and what I can add while you're deciding. Whilst I'm not new to quant finance, I am new to Upwork, and I've set my rate artificially low while I get some initial reviews. Pls see my work history, bio, and website for more information. Bayesmetricanalytics.com
    Featured Skill API Development
    Deep Learning
    Natural Language Processing
    Statistical Analysis
    Financial Analysis
    Sales Analytics
    Data Science
    Cloud Computing
    Time Series Analysis
    Machine Learning
    Quantitative Research
    Data Analysis
    Database
    SQL
    Python
  • $100 hourly
    • 0.0/5
    • (0 jobs)
    PROFILE iOS Developer first with about a decade of experience. Keen interest in smart back-end engineering and systems design. Believe in "not re-inventing the wheel" approach. Previous experience in start ups, starting up and running companies, building and managing teams, as well as taking products from idea and concept level to fully launched and profitable. Biggest praise I ever got from a client was "you're not like a normal IT guy, people can talk to you". Proven track record of remote work or at the office. Photography and coffee keep me sane and grounded, firmly believe in direct and open approach to interacting with people. Croatian national (EU), speaking Croatian (native), English and basic German., SKILLS Objective-C, Swift, SwiftUI - I've built apps from heavy UI/UX oriented, to deep iOS integration apps and full projects/solutions on Enterprise level. Mostly working on Swift these days, but equally happy to use Objective-C or transcode.
    Featured Skill API Development
    API
    Machine Learning
    Agile Project Management
    Git
    Figma
    Agile Software Development
    Firmware Programming
    Design Validation
    Apple Xcode
    Amazon Web Services
    Firebase Cloud Firestore
    Amazon DynamoDB
    iOS
  • $70 hourly
    • 4.5/5
    • (10 jobs)
    As a full stack developer with 10+ years of experience building websites and mobile applications for high-traffic brands, startups, and individuals, I'm passionate about turning ideas into reality. ✅ React & React Native: As a seasoned web and mobile app developer, React and React Native are my second nature. I build fluid, user-friendly, and visually stunning user interfaces that elevate the overall user experience. ✅ TypeScript: By incorporating TypeScript into projects, where possible, I ensure codebases are more structured, scalable, and easier to maintain. ✅ Node: Leveraging the asynchronous, event-driven architecture of Node.js, I design backends that handle concurrent connections efficiently, ensuring seamless user experiences for applications of any scale. ✅ CI/CD Pipelines: Automating the deployment process is essential for efficiency. I have designed many CI/CD pipelines that streamline development using tools such as GitHub Actions, AWS CodePipeline, Jenkins, Bitrise, and more. ✅ Testing Champion: I am a strong advocate for code quality and believe that incorporating comprehensive unit and integration testing, along with static analysis tools, helps with the delivery of bulletproof software. 🌟 Client-Focused Approach Your satisfaction is my ultimate goal. I take pride in delivering projects not only on time but also exceeding your expectations. I understand that effective communication and collaboration are key to achieving your project's success. 🔑 Let's Collaborate! Whether you need a high-impact website, a cutting-edge mobile app, or a custom software solution, I'm here to help you bring your vision to life. Reach out today, and let's discuss your project goals and how I can turn your ideas into a digital reality.
    Featured Skill API Development
    Tailwind CSS
    Hugo
    CSS
    Web Design
    Next.js
    CI/CD
    Web Accessibility
    Microservice
    Jest
    React
    JavaScript
    TypeScript
    React Native
    Node.js
  • $70 hourly
    • 3.1/5
    • (11 jobs)
    Zoho expert in consultation and developing all Zoho apps. Zoho Books, Desk, Creator, CRM, Campaigns, Recruit, etc. Deluge and API expert. Widgets and Client Script implementations. 5 years of experience in Zoho. Former direct employee of Zoho. Expert in Zoho Books implementation and migration for businesses.
    Featured Skill API Development
    CSS
    Zoho Analytics
    Zoho Survey
    Zoho Recruit
    Zoho Projects
    Zoho Books
    API
    Zoho Desk
    HTML
    Zoho CRM
    C++
    Zoho Creator
    Cloud Computing
  • $180 hourly
    • 4.1/5
    • (8 jobs)
    Hi there! I'm an MIT-trained AI expert and CTO with a specific focus on AI. To demonstrate commitment to my clients' success, I offer 10 hours of FREE work to let new clients assess our working dynamics and my expertise. Previously, I worked with big banks and led a technical team at a Snapchat-backed startup as a CTO. I love working on complex problems that require AI solutions implemented in a highly-scalable, cost-effective infrastructure that leverages the power of serverless computing and elegant user interfaces. COMMITMENT TO LONG-TERM SUCCESS 
First 10 hours for FREE! Why? Choosing the right developer for your product is a big financial decision. I get it. That's why having the time and clarity to decide without financial pressure is so important. To build a lasting partnership, I offer the following discounts to my new clients: ☝️ FREE for 10 hours to give you confidence in your selection, while allowing you to assess our working dynamics and my expertise. ✌️ 50% Discount for the first 2 weeks as we align on project goals and dive deep into the details. 🙌 25% Discount for the next 2 weeks to maintain momentum and strengthen our collaboration. If you have a small 10-hour task and are in need of help, we can still chat and see how I can help you. Please be considerate of others and don’t try to game the system! TECHNICAL EXPERTISE I am skilled in using Infrastructure as Code (IaC) frameworks, especially AWS SAM, enabling me to establish a resilient and easily navigable infrastructure. This methodology ensures streamlined deployment, monitoring, and updates to your infrastructure, irrespective of its complexity. On the front-end development front, TypeScript is my go-to language, providing the highest degree of precision and safety in our rapidly evolving tech environment. With over 5 years of hands-on experience with React Native, I have successfully built production-grade, cross-platform apps that cater to tens of thousands of users. 🤖 AI/ML Expertise: * Generative/LLMs: GPT-4, DALL-E 2, MidJourney, Stable Diffusion. * Deep Learning: Transformers, CNN, RCNN, YOLO v7 * Neural Networks: Perceptron, MLP, Hopfield Network * Regression techniques: OLS, Linear/Logistic/Ridge/Multi-Output Regression, LASSO * Bayesian methods: Naïve Bayes, Gaussian Naïve Bayes * Clustering: K Means, Hierarchical Clustering * Dimensionality reduction: PCA, LDA, t-SNE * Ensemble methods: Bootstrap Aggregation, AdaBoost, Blending * Frameworks/libraries: TensorFlow, Keras, PyTorch, Caffe, Scikit-Learn, NLTK, Hugging Face, OpenCV, LangChain, Pinecone, Chroma, ChatGPT Plugins Languages: Python, JavaScript, TypeScript. FIRST PRINCIPLES 📐 Simplicity: I follow the principle of least privilege for enhanced security. Adopting a component-driven approach ensures easier implementation, maintenance, and documentation. 📈 Scalability: My designs, crafted with growth in mind, seamlessly combine event-driven components and Function-as-a-Service (FaaS) serverless infrastructure for innate scalability. 💰 Cost-efficiency: By building serverless architectures tailored to a specific use case, I'm dedicated to ensuring my clients only pay for what's essential, cutting down on redundant costs. ✅ Quality: To maintain code consistency, I rely on tools like ESLint and Prettier, always backed by a comprehensive suite of unit, integration, and smoke tests. 📱 Product focus: After spending five years in startups, I understand the importance of aligning tech and product visions. I always aim to find the best technical solutions that support product goals. LEARN MORE I invite you to explore my GitHub profile for insights into my past projects and a firsthand look at the quality of my work. I'm eager to connect and discuss how I can contribute to your objectives. Talk to you soon!
    Featured Skill API Development
    Machine Learning
    CI/CD
    Artificial Intelligence
    Deep Learning
    ChatGPT
    Prompt Engineering
    TypeScript
    JavaScript
    React
    React Native
    Python
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