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Hire the best API Developers in Warsaw, PL

Check out API Developers in Warsaw, PL with the skills you need for your next job.
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  • $35 hourly
    • 4.1/5
    • (6 jobs)
    I'm a Python developer from Poland with more than 4 years of experience working with frameworks Odoo, Scrapy, Selenium and etc. I can help with site's data extraction, scrape pdf, build API, creating Discord or Telegram bot and etc. I easily collaborate with other developers, project managers, and stakeholders. I'm good at understanding project requirements, designing software solutions, and then implementing them using Python and related technologies. Testing, debugging, and maintaining the codebase to ensure that software is running smoothly and meeting the needs of end-users will also be my responsibility. Personal qualities - communicative, good team player, responsible, non-conflict, quick learning skills, organizational skills, multitasking, understanding the importance of work.
    Featured Skill API Development
    Python Script
    Odoo Development
    Odoo
    Django
    API
    JavaScript
    Scripting
    Selenium
    Scrapy
    Data Extraction
    Python
    Data Scraping
    Data Mining
  • $29 hourly
    • 5.0/5
    • (7 jobs)
    I'm a Senior Full Stack Developer with 10+ years of experience in Full Stack development. 🏆 Certified Senior Full Stack Developer in React.js, Node.js, Next.js, Nest.js, ExpressJS 🏆 Top Rated Upwork Full Stack Developer React Node.js 💎 10+ Years of commercial experience as a Full Stack Developer 🏆 20+ Successfully finished projects on Upwork with 5 stars feedback 🕒 1500+ Total Working Hours on Upwork 🏆 Master's Degree in Computer Science , I have strong experience in providing development services: 💎 As Front End Developer - Creating responsive and user-friendly interfaces on React and Next.js. 💎 As Back End Developer - Building robust and scalable server-side applications and APIs on Node.js. It also could be NestJS backend or ExpressJS backend as I'm NestJS developer and Express JS developer, too 💎 As Full Stack Developer - Providing comprehensive solutions by writing clean, maintainable, and reusable code, covering both front-end and back-end development, also working with MERN stack. I have strong and proven expertise & skills in: 🛠 Front-End Development - React, Next.js 🛠 Back-End Development - Node.js, Nest.js, Express.js 🛠 Database - MongoDB, Firebase, MySQL, PostgreSQL, Supabase 🛠 Programming Languages - JavaScript, TypeScript 🛠 Communication - RESTful APIs, GraphQL, WebSockets 🛠 Design Tools - Figma, Adobe XD, Sketch 🛠 Version Control - Git & GitHub & GitLab & Bitbucket 🛠 CI/CD - Jenkins GitLab CI 🛠 Project Management - Jira, Trello, Asana, Notion 🛠 Testing Frameworks - Jest, Mocha, Unit testing 🛠 Libraries - Bootstrap, Moment.js, Redux, Redux-toolkit, Redux-saga, Material-UI, React-query, Axios, Sequelize, TypeORM, Socket.IO, JsonWebToken, Formik, React Hook Fosm, ANTD, Storybook, Highcharts, RxJs; Tailwind CSS; React Twilio Why My Full Stack Development Solutions Stand Out:
 📍 I successfully built and maintained a lot of scalable SaaS solutions, Web applications (web apps), websites, landing pages, PWA, SPA, Admin Panels, CRM, ERP, E-commerce marketplaces, IoT, Proof of Concept (POC), MVP, machine learning, Booking platforms, Shopify apps, E-learning platforms, Finance apps, chatbot development, Stock trading app for day trading and others. 📍I have proven experience in development for: E-commerce, Healthcare, Real Estate, Education, Fintech, AI solutions, Management, Travel and Hospitality. 📍 I successfully integrated: WebSockets, RESTful APIs, and third-party APIs such as: Stripe API, Zoom API, OpenAI API, ChatGPT, shopify plugin, capacitor vue, wordpress speed. 📍 Have proven experience with such authorization services: OAuth, JWT, OAuth2, Web Tokens As I enjoy thinking outside the box my clients got the next extra benefits: ✅ +20% Efficiency Increase: My work helps projects be delivered faster using streamline workflow and agile methods. I write code efficiently so products reach the market quickly. ✅ +30% User Engagement Enhance: My designs and responsive interfaces attract users and make them interact more, which leads to higher satisfaction and conversion rates that grow business. ✅ 100% Scalability & Performance: I build systems that can handle heavy traffic with fast performance and very little downtime. This supports your business operation success. ✅ 100% Custom Fit Solutions: I create tailor-made solutions that match each client's business needs, resulting in real improvements in productivity and ROI. ✅ 15% Cost Saving: By optimizing code and infrastructure, my solution reduces long-term maintenance costs and resource expenses, saving money for business. 🏆 As an Expert in Full Stack development, I have strong experience working as: React Developer, Front end Developer, Back end Developer, Full-Stack developer, Full Stack React Developer, JavaScript Developer, React JS Developer, React Web Developer, Nest.js developer, MERN Stack developer, Software developer, Web developer, SaaS developer, Full Stack developer React, Next.js Developer, Node.js Developer, WordPress developer, React Native developer, Mobile App developer, Python rest api developer, Python developer, Java developer, Python NodeJS developer, React Native Full Stack developer and DBA, SaaS marketing adviser, front end WordPress, Full Stack Web developer, API developer, JavaScript Developer. Also, helped with UX UI web design as a ui ux designer. Have experience working with: angular, laravel, ruby on rails, spring framework. I excel both as an independent developer and as part of a team, and I would be delighted to collaborate with your team if the opportunity arises. As an Expert Full Stack Developer and CEO of a Development company, I'm ready to elevate your project to new heights of success! 🚀🚀🚀
    Featured Skill API Development
    AI Development
    Full-Stack Development
    API
    Tailwind CSS
    Next.js
    ExpressJS
    RESTful API
    Web Development
    JavaScript
    TypeScript
    MongoDB
    Node.js
    React
  • $40 hourly
    • 5.0/5
    • (44 jobs)
    👋 Nice to meet you, I’m Alena 🍋 For over 7 years, I’ve been working in Salesforce development and administration. I value honest relationships and delivering high-quality work. Led a team of 15 professionals to complete projects on time and within budget 🟡 I have been building, improving, and managing a variety of systems with diverse user bases and business types to meet clients' requirements. My passion lies in AppExchange product development, and I have successfully listed multiple packages and passed the Security Review. 🟡 Handle all aspects of the Salesforce.com platform, including Sales Cloud, Service Cloud, Experience Cloud, B2B Commerce, CPQ, and Pardot. Assignments I can complete: ☁️ Any Salesforce implementations and customization ☁️ SaaS development ☁️ Custom Salesforce development. Backend and frontend (Apex, VF, Lightning, Aura, LWC). ☁️ API Integrations with other platforms, apps ☁️ Data migration from other CRMs ☁️ AppExchange product development ☁️ Security review for AppExchange ☁️ Support & Maintenance of existing Salesforce apps ☁️ Hybrid applications development. Ionic, Cordova ☁️ UI/UX Frontend (JavaScript, JQuery, Angular, ReactJS, VueJS, CSS3, HTML5) ☁️ Heroku or AWS Backend (NodeJS, PHP, MySQL, PostgreSQL, MongoDB). Your goal is my mission 💛 ✉️ Contact me, and we’ll achieve it together!
    Featured Skill API Development
    API
    Commerce Cloud
    Heroku
    Apex
    Salesforce App Development
    Salesforce Service Cloud
    Dashboard
    Salesforce
    Visualforce
    AppExchange
    Salesforce Lightning
    Hybrid App Development
    Salesforce CRM
    Node.js
  • $50 hourly
    • 5.0/5
    • (9 jobs)
    I'm an e-commerce expert with over 7 years of experience in the field. My journey as a developer and e-com consultant started with Magento 2 (I'm a certified Magento 2 Specialist) and Woocommerce. For the past 3 years, I've been doing Shopify projects exclusively. - Shopify Theme Development - Shopify App Development - Shopify Support - Shopify Consulting - Shopify Storefront APIs - Migrations from any other e-commerce platform to Shopify - Shopify Design - Shopify bulk product upload - Shopify SEO - Shopify conversion rate optimization - Shopify Store marketing Stores I've made or was involved with: Suzie Store - kids clothing brand (design, theme development, bulk product upload, CRO) Neon Signature - Led Neon Sign production company (I developed the interactive neon signs constructor from scratch, as well as did the theme development, product bulk upload, CRO) Hargroves Cycles - one of the biggest bike retailers in the UK (design, theme development, bulk product upload, app development)
    Featured Skill API Development
    React Native
    Ecommerce Website Development
    Shopify Templates
    MySQL
    PHP
    CSS
    React
    Shopify
    HTML
    HTML5
  • $50 hourly
    • 5.0/5
    • (6 jobs)
    Hi 👋! If you are looking for a Full Stack Software engineer, then you are in the right place! I have more than 5 years of experience in full-cycle development and have successfully completed several huge web projects. My expertise is ⤵️ ✔️.NET ✔️ASP.NET ✔️ASP.NET MVC 5 ✔️Razor Pages ✔️EntityFramework ✔️HTML ✔️CSS (SCSS) ✔️Bootstrap ✔️JavaScript ✔️React.js (Redux, RESTful API, React Router) I'm result-oriented person, always trying to find optimal solution and making your business work faster⚡️
    Featured Skill API Development
    Code Refactoring
    .NET Core
    TypeScript
    ASP
    CSS
    Git
    Microsoft SQL Server
    C#
    JavaScript
    HTML
    AJAX
    jQuery
    GitLab
    Entity Framework
  • $39 hourly
    • 5.0/5
    • (4 jobs)
    I have worked in full stack engineering for my entire over 15 years career. As a senior full-stack developer proficient in JavaScript/TypeScript, PHP, Python, I bring a comprehensive skill set to every project, seamlessly integrating cutting-edge technologies and frameworks such as Codeigniter, Laravel, React, Vue to make the goal of client. SKILLS - PHP, MySQL (15 years of experience) - HTML, JavaScript, jQuery, CSS (15 years of experience) - Yii, Codeigniter, Laravel (10 years of experience) - Yii, Codeigniter, Laravel (10 years of experience) - React, NodeJs (5 years of experience) - Vue, Angular (2 years of experience) Thank you in advance for your time and consideration. I look forward to working with you soon.
    Featured Skill API Development
    PHP
    React
    Database
    International Development
    API
    Database Management System
    Product Development
    Review
    Code Review
    GitLab
    Docker
    CSS 3
    Git
    HTML5
  • $40 hourly
    • 4.5/5
    • (29 jobs)
    🚀 Certified Salesforce Developer | Workflow Automation Expert | API Integration Specialist| Industry-Specific Solutions | Web Portals Looking for a seasoned Salesforce expert to transform your business processes and drive efficiency? With 14 years of experience, I specialize in designing and implementing tailored Salesforce solutions that align with your industry’s unique requirements. My goal is to help you leverage Salesforce to streamline workflows, improve customer experiences, and solve complex challenges. ☁Customized Salesforce solutions for industries such as Financial Services, Recruiting, Wholesale, eCommerce, Education, Marketing, Hospitality, and more. ☁Ensure the platform is optimized to meet the demands of your specific business model. What I Can Do for You: 💥Salesforce Customization: Tailored solutions to meet your unique business needs, from process automation to advanced reporting. 💥API Integrations: Seamless integration of Salesforce with tools like Google Sheets, NextGen, and other CRMs or EHR systems. 💥Data Automation: Real-time synchronization, dynamic reporting, and analytics dashboards. 💥Problem-Solving Expertise: From debugging to scaling existing systems, I ensure your processes are always optimized. Why Choose Me? ✅Proven track record of delivering high-quality, efficient solutions. ✅Expertise in creating HIPAA-compliant workflows for sensitive industries. ✅Strong communication skills to ensure we’re always on the same page. ✅Commitment to deadlines and excellence – your satisfaction is my priority. Results You Can Expect: 📌Streamlined business processes tailored to your industry. 📌Enhanced customer and partner experience through modernized digital tools. 📌Increased operational efficiency and reduced manual effort. If you're looking for someone who can deliver innovative solutions, prioritize your goals, and ensure seamless execution, I’d love to chat! Let’s discuss your project and how I can help you achieve your business objectives. 📩 Contact me now to discuss your project and take the next step toward success☁
    Featured Skill API Development
    Web Application
    Salesforce App Development
    Node.js
    MySQL
    AppExchange
    Salesforce Marketing Cloud
    JavaScript
    Visualforce
    Salesforce
    Salesforce Service Cloud
    Salesforce Sales Cloud
    Salesforce Lightning
    Apex
    Salesforce CRM
  • $40 hourly
    • 5.0/5
    • (33 jobs)
    Hi guys, I am a Senior Salesforce Developer and Solution Architect with over 16 years of experience. My Salesforce journey began in 2008 and I have been specializing in: - AppExchange application development & Security review - Salesforce API integrations - Migration from any other system (Hubspot, Zoho, Microsoft, etc) to Salesforce - Experience (Community), Sales, Service, Marketing, Health, Commerce clouds implementation and enhancements - Hybrid app development - Long-term support with any of your Salesforce needs. I am also the founder of a Salesforce ISV and Consulting partner and lead a dedicated team of specialists in Poland. Drop me a line anyime and let's work together to make your Salesforce journey more efficient and effective.
    Featured Skill API Development
    HTML
    API Integration
    Heroku
    Salesforce App Development
    Salesforce Email Studio
    JavaScript
    Visualforce
    Salesforce
    Salesforce Marketing Cloud
    Salesforce Sales Cloud
    Salesforce Service Cloud
    Salesforce Lightning
    Salesforce CRM
    Apex
  • $60 hourly
    • 4.9/5
    • (17 jobs)
    With a rich background in software development, I specialize in Java and related technologies. My experience spans teaching, back-end development, and architecture, involving diverse projects from large-scale platforms to tailored client applications. Currently, I focus on designing and deploying cloud-based back-end solutions with a specialization in serverless architecture, security, integrations, and databases. I've collaborated with global corporations, provided consultancy services, and freelanced for SMEs and startups. My project portfolio ranges from high-traffic e-commerce applications to data-centric and cutting-edge solutions like low-code platforms and AI-integrated tools. Leveraging my extensive experience, I not only offer technical expertise but also provide valuable business insights to clients, advising on the strategic aspects of their applications. Moreover, I hold AWS certifications and boast a strong educational background with degrees in Computer Science and Organization Management.
    Featured Skill API Development
    Amazon S3
    Continuous Integration
    Amazon EC2
    AWS Lambda
    AngularJS
    Hibernate
    Spring Framework
    Java
    SQL
  • $39 hourly
    • 5.0/5
    • (37 jobs)
    Full-stack web developer with solid experience in PHP, MySQL, JavaScript, AJAX, jQuery, HTML, CSS, and Bootstrap. I write clean, efficient, and scalable code using modern tools and best practices — including Git for version control and tools like cURL and Guzzle for external integrations. I work with both custom-built CMS platforms and popular systems such as WordPress, OpenCart, ZenCart, LiveStreet, InstantCMS, Joomla, DLE, Magento, ocStore, and Osclass — allowing me to adapt to a wide range of project requirements. Seamless API integration is a core part of my work. I’ve connected applications with services like Google, YouTube, 2Checkout, Last.fm, SoundCloud, AssistAPI, WebPay — as well as major cryptocurrency exchange APIs (Binance, Bybit, OKX, etc.). My crypto-related experience includes building dashboards, trading bots, price trackers, and other automated systems. I also develop custom data tools — including parsers, scrapers, and content generators — to help clients automate processes, collect insights, and scale faster. Some of the projects I’ve contributed to include: ecarstrade.com, availabletradeinternational.com, stabot.ru, despotdepot.com, discount-supplements.co.uk, targowy.pl, belpodium.ru, rusmunich.info, automalinovka.com, and others. If you're looking for a reliable developer who delivers high-quality results and understands both technical and business needs — let’s work together.
    Featured Skill API Development
    Data Mining
    CSS
    HTML
    AJAX
    jQuery
    MySQL
    Google Maps API
    JavaScript
    Data Scraping
    PHP
  • $65 hourly
    • 5.0/5
    • (4 jobs)
    Ruby on Rails Architect with 10+ years of expertise in building and scaling web applications for Marketplaces, CRM systems, and Fintech. Sold my first desktop app at 13. Integrated ML model that helped to save $30K monthly. One of the first Amazon Elastic Kubernetes Service users Master of Science in Engineering Tech skills: • Full cycle of application development from scratch for monolithic & microservices architecture. Ruby, Ruby on Rails, Python, Django, Flask • Database design and optimization - PostgreSQL, MySQL, SQLite. Redis • Search engines - Solr, ElasticSearch, Sphinx • Frontend solutions - Javascript, jQuery, Bootstrap, Stimulus, VueJS, ReactJS • Deployment, provisioning, and containerization - Capistrano, Ansible, Heroku, Docker, Kubernetes • Application tests coverage and CI/CD configuration - BuildKite, Jenkins, CircleCI, GitHub Actions • Background processing - Resque, Sidekiq, Whenever, Delayed Job, Sneakers, etc • Push notifications - Firebase • Message queues - RabbitMQ, AWS SQS • General and high-load application optimization • Coud infrastructure: Amazon Web Services: ELB, EC2, RDS, SQS, ECR, ECS, EKS, Cloudfront, Cloudwatch Heroku & addons, VPS instances • Ruby on Rails cybersecurity monitoring • Building public & private APIs - RestAPI & GraphQL • API Integrations: AI: GhatGPT, Image recognition, Image scoring Payments & subscription: Stripe, PayPal, ChargeBee, Chargify Social networks: Facebook, Instagram, Twitter, Google, Telegram Media: Cloudinary, AWS S3, Youtube, Dropbox, Google Drive Marketing: Mailchimp, FB pixel, Hubspot, Google Ads, GTM, Firebase, Twilio, SendGrid, Keitaro, Amplitude, Mailgun, GTM Messengers & bots: Slack, Telegram KYC: KycMatic, Onfido, SumSub Geolocation: PostGIS, OpenStreetMap, Google Maps, Geocoder Other: Datadog, Sentry, NewRelic, Rollbar, Grafana, PaperTrail, Recaptha, Spotify, Apple, Turnstile • Project Management: Agile, Scrum, Market Research, Technical Documentation, Data Analysis and Interpretation, Marketing & Sales, Atlassian Jira, Confluence, Trello, Todoist, Clickup
    Featured Skill API Development
    Ecommerce Backup & Migration
    Payment Gateway Integration
    App Development
    Ecommerce Development Consultation
    Ecommerce Website
    MySQL
    Stripe
    Elasticsearch
    Apache Solr
    PostgreSQL
    PayPal
    Sphinx
    Ruby on Rails
    Amazon Web Services
  • $40 hourly
    • 5.0/5
    • (35 jobs)
    Poland-based Senior Salesforce developer with 8 years of expertise in: ‧ Salesforce Experience (Community), Marketing, Sales, Service, Health, Nonprofit, Commerce Clouds ‧ AppExchange application development, Security review and ongoing support ‧ Salesforce API integrations (Stripe, Mailchimp, DocuSign, Quickbooks online, HubSpot, Zendesk, etc.) ‧ Migration from any other CRM to Salesforce (HubSpot, ServiceNow, Monday, Pipedrive, etc.) ‧ Salesforce implementation & custom development ‧ Salesforce Solution architecture design and data modeling I am with a Salesforce ISV & Consulting partner team in Poland, let's enhance your Salesforce journey now! ☁
    Featured Skill API Development
    Salesforce
    Salesforce Marketing Cloud
    Salesforce Service Cloud
    Salesforce Sales Cloud
    Salesforce App Development
    AppExchange
    Visualforce
    Salesforce Lightning
    Apex
    Salesforce CRM
    JavaScript
    Node.js
    Web Application
    API Integration
  • $40 hourly
    • 5.0/5
    • (13 jobs)
    I’m a seasoned Fullstack PHP Developer with extensive experience in crafting complex Software-as-a-Service (SaaS) applications from scratch. Specializing in the Laravel framework, I have a deep understanding of OOP and adhere to the highest coding standards (SOLID/KISS/DRY) to ensure clean, maintainable, scalable and efficient code. Beyond typical web development skills, I have a profound knowledge AI (beyond a simple API integration), which allows me to design and seamlessly integrate AI capabilities to any web app. Key Expertise: - Fullstack Development: Proficient in both backend and frontend technologies with a focus on PHP (Laravel) and JavaScript. - SaaS Applications: Experienced in designing and building scalable SaaS platforms from the ground up, tailored to unique business needs. - AI Integration: Skilled in seamlessly integrating AI features to any web app. - Best Practices: Committed to code quality, security, and performance optimization. Why Choose Me? - Proven Track: 100% job success and more than 31500 hours worked on Upwork! - Collaborative Approach: Excellent communicator, I believe in building strong working relationships and am committed to understanding and meeting your project requirements. - Continuous Improvement: Passionate about learning and adopting new technologies and methodologies to stay at the forefront of the development landscape. Whether you are starting a new project from the ground up or looking to enhance an existing application, I am here to help you achieve your goals with precision and professionalism. Let's connect and bring your vision to reality with cutting-edge technology and top-quality implementation.
    Featured Skill API Development
    RESTful Architecture
    Object-Relational Mapping
    MVC Framework
    PHP
    Vue.js
    Laravel
    AJAX
    JavaScript
    jQuery
  • $40 hourly
    • 4.3/5
    • (42 jobs)
    Software development expert with more than 9 years of experience. I have a bachelor's degree in software development and information technology. Mainly focused on development of complex custom web applications. Experienced both in backend and frontend development. My tech stack: Python, Django, DRF, DRF JSON API, Flask, FastAPI, Celery, Docker, Docker-compose, HTML, CSS, JS, Less/Sass, Ansible, VueJs, Vuex, Nuxt, Vuetfiy
    Featured Skill API Development
    Web Design
    Web Development
    React
    Django
    SQLAlchemy
    Automation
    Vue.js
    Website Optimization
    Landing Page
    HTML
    PostgreSQL
    Python
    CSS
    JavaScript
  • $50 hourly
    • 0.0/5
    • (0 jobs)
    My experience includes 20+ years in cloud telephony and contact centre solutions. My professional interests are high-loaded cloud voice and text communication and AI automation technologies like speech and NLP. I'm proud I've played a significant role in projects processing millions of calls and chats. Moreover, with our team, we have developed a Conversational AI Platform — a complete solution designed to help companies expand and improve their services quickly. This platform offers a no-code development solution that helps businesses design, develop, and integrate intelligent IVR, voice bots, and chatbots. The platform is for digital service providers, startups, and B2B/B2C businesses looking to enhance their services, improve customer interactions, and cut costs through automation. Learn more about the platform by following the link provided in the portfolio section below.
    Featured Skill API Development
    Cloud Computing
    Chatbot Development
    VoIP
    FreeSWITCH
    Product Development
    RabbitMQ
    Automatic Speech Recognition
    API
    Python
    PostgreSQL
    Cloud Services
    C++
    RESTful API
    Architecture
    Architectural Design
  • $32 hourly
    • 0.0/5
    • (0 jobs)
    I am a .Net backend developer, and sometimes take responsibilities as a DevOps, interesting in ML English - Fluent Russian - Academic Belorussian - Fluent
    Featured Skill API Development
    Continuous Integration
    .NET Core
    CI/CD
    DevOps
    ASP.NET Web API
    Microsoft Active Directory
    Microsoft Azure
    Docker
    RESTful API
    ASP.NET
    .NET Framework
  • $40 hourly
    • 0.0/5
    • (0 jobs)
    👋 In IT since 2009. Experience in Development for Custom Business Solutions domains since 2013. Experienced in API design, database design, data modeling, and building complex solutions that meet business requirements. Clean code supporter. My strengths are good communication, project management, problem-solving skills, and getting things done. Well-focused and can meet the expected deadlines. Why me? ● 10+ years of experience ● Proactivity and Autonomy ● Regular communication ● Problem-solving skills ● Getting things done. Who am I ● 10+ years of experience in all phases of the Software Development Life Cycle (SDLC) ● Wide experience using Open Source frameworks. ● Expert knowledge in designing and developing complex applications. ● I extensively worked with the Java / J2EE design patterns and regular expressions. ● Experienced in database design and data modeling. ● Extensive experience in Client-Server architecture and MVC frameworks. ● Highly motivated, results-oriented, and has leadership skills and great team ethics. ● Good Communication, interpersonal skills, and problem-solving skills. ● Well-focused and can meet the expected deadlines. What do I know? ● Java 7 - 21 expertise: ● Spring: Core, Data, DI, AWS, DB migrations, Rest Services, API modeling, gRPC, SOAP ● DB: SQL, noSQL ● Messaging: Rabbit MQ, SNS, SQS, Kafka ● Build tools: Maven, Gradle ● Testing: JUnit, Mockito ● VCS: Git, Subversion ● Containerization: Docker, Kubernetes ● CI/CD: Jenkins, Gitlab ● CLI: bash ● OS: any ● Networks technologies advanced level of understanding ● Microservices Architecture
    Featured Skill API Development
    Web API
    SQL
    Amazon Web Services
    Web Development
    API Integration
    REST API
    Integration Testing
    API
    PostgreSQL
    Apache Maven
    Spring MVC
    Spring Framework
    Spring Boot
    Java
  • $5 hourly
    • 5.0/5
    • (1 job)
    I'm a semi-experienced app developer. - API Creation - Node/React Web Develpment - C# .Net Framework Accesibility Polish Native Speaker
    Featured Skill API Development
    Software
    C++
    Web Development
    React
    .NET Framework
    C#
    Node.js
    JavaScript
  • $78 hourly
    • 0.0/5
    • (0 jobs)
    I have 12+ years of experience in different roles; Product Owner, Business & System Designer, Analyst. Gained technical and business background in industrial sectors: energy , automotive, maps, and first steps in fintech area. Experienced in: product management and business design, research & innovation, lean and agile methodologies, requirements and business needs elicitation, problem solving, BI data analytics and insights reports, processes optimization. Currently: >> ProductOps: Engineer and Product Consultant - hands-on Python / FastAPI - prototyping, PoC, hypothesis verification and MVP for new initiatives >> Data-driven, business and IT solutions designer. >> B2B cooperation within new and digital products delivery. Quick summary of previous experience: >> 4+ years of experience at Transition Technologies related to research, design and implementation of dedicated IT solutions for energy sector. Responsible for Billing System - product for
    Featured Skill API Development
    Product Management
    Generative AI
    Artificial Intelligence
    Scripting
    Database
    API
    API Documentation
    Design Analysis
    Terraform
    FastAPI
    Python
    Claude 3.5 Sonnet
    OpenAI API
  • $32 hourly
    • 5.0/5
    • (11 jobs)
    I am a freelancer, full stack developer, and have great experience as python/django/javascript/typescript frameworks (like VueJS, Angular, ReactJS, jQuery) programmer. Also familiar with AI and Machine Learning concepts. I worked many (9) years as python/django/javascript programmer for one of the bigest magazine publishers in Poland (Murator S.A.) related to housing, daily news, fashion & styles, health. So I know what efficient, scalable, well optimised for big traffic, safe, seo friendly, covered with tests and professional code mean. I am not only a backend developer, but have a good experience in many frontend technologies like (angularjs, vuejs, jquery; sass, css3, typescript). I am able to build sites from scratch and help you to design your application (but I am not a graphic designer) Main technologies: 1. Python technologies: - Django (15 years of experience) - Flask - REST API - Pandas, PyCaret, OpenAI, Streamlit, and other related to AI, ML, EDA 2. Javascript technologies: - Typescript - Vue.js - Angular - ReactJS - Ionic - AngularJS - Jquery + jquery UI - ESLint - Chrome extensions 3. Other frontend technologies: - CSS, Sass, html5, Bootstrap 4. databases: - Mysql, - Postgres, - Sqlite - Non-relational databases: MongoDB 5. Other technologies: - pdfkit, wkhtmltopdf (generating pdf-s) - Webpack - Nginx - GIT - Payment APIs (PayPal, Stripe) 6. Additionaly (python-related technologies): - Pytest - Selenium - Mongoengine - PEP8, Flake8 (using this as a hook in git) - wxPython - Jinja2 - Pillow - Haystack - Celery Also had experience with: - Redis
    Featured Skill API Development
    HTML5
    AngularJS
    Ubuntu
    Stripe API
    Vue.js
    jQuery
    CSS 3
    Flask
    MongoDB
    Sass
    Python
    Django
  • $50 hourly
    • 0.0/5
    • (0 jobs)
    With 8+ years of experience in software development, I specialize in ETL, Big Data, and AI technologies, enabling businesses to build scalable, efficient, and reliable data-driven solutions. ✅ End-to-End Expertise – I handle analysis, development, deployment, and monitoring, ensuring your software is both robust and maintainable. ✅ Custom Data Pipelines – I design and implement tailored ETL workflows that optimize data flow and processing for your specific business needs. ✅ AI & RAG Solutions – Leveraging cutting-edge LLMs, retrieval-augmented generation (RAG), and machine learning, I build intelligent, high-performing applications. Let’s discuss how I can help you transform your data into actionable insights and AI-powered solutions!
    Featured Skill API Development
    API Integration
    Indexing
    Database
    Python
    Chatbot
    Data Engineering
    Vector Database
    LangChain
    Prompt Engineering
    Retrieval Augmented Generation
    Large Language Model
  • $34 hourly
    • 0.0/5
    • (2 jobs)
    Ambitious young developer. Made in Russia, but currently in Poland. Open to cooperate with good products. You will definitely like our partnership. Code in JavaScript (NodeJs, Typescript, VueJs). Acknowledge with AWS systems, SQL/noSQL databases, real-time apps, elasticsearch.
    Featured Skill API Development
    RESTful API
    AWS Lambda
    Elasticsearch
    Nuxt.js
    MongoDB
    JavaScript
    MySQL
    Node.js
    Vue.js
  • $17 hourly
    • 5.0/5
    • (1 job)
    As a developer, I possess over six years of commercial development experience, having worked with both large enterprise projects and small startups. I take pride in receiving great reviews from all my clients for my work. Whether working solo or as part of a large team, I focus on ensuring the success of your application and utilize all of my expertise to help your business thrive. It's worth noting that my contributions extend beyond mere code writing. Top Skills: - JavaScript / ES6 / Typescript - React / Next.js - React Native - Angular / Ionic - Node.js / Nest.js - Flutter (Android & iOS development) - Firebase Also I have an experience with Tailwind, GraphQL, Apollo, PostgresQL, Amazon services (S3, Cloudfront, EC2 and etc.), Docker, Bash scripts. If you're seeking an excellent solution for your ideas, please feel free to get in touch with me.
    Featured Skill API Development
    CSS
    Next.js
    Web Development
    Angular
    TypeScript
    React Native
    JavaScript
    Firebase
    HTML5
    React
    Node.js
    Mobile App Development
    Ionic Framework
    Flutter
  • $25 hourly
    • 4.1/5
    • (2 jobs)
    Available for new project II Always using latest trends in developemnt II Direct communication with client ➡️ SERVICES +Profound Angular proficiency encompassing Angular Material, Angular Universal, and Angular 2+ +A holistic grasp of web application security and performance optimization +Navigating the intricacies of RESTful APIs with ease +Seamless collaboration with cross-functional teams including UI/UX designers, product managers, and backend developers ➡️ EXPERTISE Mastering the arts of 𝐉𝐚𝐯𝐚𝐒𝐜𝐫𝐢𝐩𝐭, 𝐓𝐲𝐩𝐞𝐒𝐜𝐫𝐢𝐩𝐭 Crafting seamless experiences with 𝐀𝐧𝐠𝐮𝐥𝐚𝐫𝟐+ 𝐚𝐧𝐝 𝐈𝐨𝐧𝐢𝐜 Navigating the 𝐍𝐨𝐝𝐞𝐉𝐒 landscape alongside 𝐄𝐱𝐩𝐫𝐞𝐬𝐬.𝐣𝐬 Empowering cross-platform apps with 𝐂𝐨𝐫𝐝𝐨𝐯𝐚 𝐚𝐧𝐝 𝐂𝐚𝐩𝐚𝐜𝐢𝐭𝐨𝐫 Expertise in 𝐇𝐓𝐌𝐋, 𝐂𝐒𝐒, 𝐒𝐂𝐒𝐒, 𝐋𝐄𝐒𝐒, 𝐁𝐨𝐨𝐭𝐬𝐭𝐫𝐚𝐩, 𝐚𝐧𝐝 𝐅𝐢𝐫𝐞𝐛𝐚𝐬𝐞 Harnessing the power of 𝐌𝐨𝐧𝐠𝐨𝐃𝐁, 𝐌𝐲𝐒𝐐𝐋, 𝐚𝐧𝐝 𝐅𝐢𝐫𝐞𝐛𝐚𝐬𝐞 Skilled in 𝐀𝐖𝐒 𝐚𝐧𝐝 𝐍𝐑𝐖𝐋 Moreover, my proffessional English skills facilitate smooth communication. If you're seeking a 𝐟𝐮𝐥𝐥-𝐭𝐢𝐦𝐞, 𝐥𝐨𝐧𝐠-𝐭𝐞𝐫𝐦 partner for your projects, I'm at your service. Feel free to reach out and let's bring your ideas to life!
    Featured Skill API Development
    Web Application Framework
    NodeJS Framework
    Front-End Development
    Web Application Development
    Mobile Angular UI
    AI Development
    Full-Stack Development
    TypeScript
    JavaScript
    Desktop Application
    Web Application
    Web Development
    Node.js
    Angular
  • $30 hourly
    • 0.0/5
    • (0 jobs)
    Greetings! I have been working as a Java developer for more than 7 years, my main clients are from Europe and USA. I am developeping backend systems(APIs, microservices, integrations, etc). You can safely entrust me with the work on your project and will never be disappointed in our cooperation, I can guarantee the high responsibility and quality of the tasks that I carry out, which you can be sure of when you take me to your team. Main technologies: - Java 11, 17, 21 - Spring: Core, MVC, Boot, Data, Security, Config, Cloud - AWS: DynamoDB, RDS, S3, Cognito, IAM, SQS, SNS, etc - JUnit - JMS: Kafka, RabbitMQ - JDBC, Hibernate 3.x - Docker, Jenkins - etc
    Featured Skill API Development
    Docker
    PostgreSQL
    Apache Kafka
    Database
    API Integration
    Kotlin
    Spring Framework
    Java
    Amazon Web Services
    Software Development
  • $25 hourly
    • 5.0/5
    • (2 jobs)
    Hi! I am Python developer. Over the course of a year, I developed the Tasker application as part of a small team. I was responsible for creating features, API, text chat, tests. Right now as a freelancer I am involved in a project from Interexy. The work is related to algorithms. I've only been studying programming for a few years. During this time I have written a lot of bots and parsers for myself and to order. I offer many services on the Fiverr. I am actively looking for a job and realize the peculiarity of the current situation. My skills: * Python3 * Django, Flask, FastAPI * MySQL, PosgresQL * Redis, RabbitMQ * Docker, Git, GitHub * Pytest * Selenium, BS4 * Telethon, aiogram Feel free to contact me Welcome!
    Featured Skill API Development
    Chatbot
    Server Administration
    Bot Development
    API
    Telegram API
    Telegram
    Python
  • $70 hourly
    • 0.0/5
    • (0 jobs)
    I am a systems optimization engineer specializing in automation, efficiency improvements, and building scalable solutions. My approach focuses on creating reliable and structured systems that reduce load, eliminate bottlenecks, and make processes more predictable and manageable. Key areas of expertise: Server optimization and load balancing Automation of processes and complex system integrations Development of reliable backend solutions Implementation of effective monitoring and control mechanisms Optimization of business processes, eliminating inefficiencies and reducing time costs I don't just write code—I design well-thought-out, structured systems that operate efficiently, reliably, and without unnecessary overhead.
    Featured Skill API Development
    Business Analysis
    Server Administration
    Process Architecture
    System Administration
    MySQL
    PHP
    Node.js
    JavaScript
    Python
    DevOps
    Problem Solving
    Database
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