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Hire the best Backend Rest API Freelancers in Serbia

Check out Backend Rest API Freelancers in Serbia with the skills you need for your next job.
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  • $60 hourly
    • 5.0/5
    • (6 jobs)
    Results-oriented Sr. Software Engineer with 6 years of experience in enterprise software development. Certified AWS Associate Developer with strong cloud skills coupled with top-notch Python knowledge and solid expertise in developing scalable backend solutions. I have a proven track record in designing cost-efficient architectures, optimizing application performance up to 70%, and streamlining SDLC processes for time savings. Contributed to Open-Source initiatives. Key Skills 🧑‍💻: • Top-notch experience and expert knowledge of Python and its frameworks (Django, Flask, FastAPI, AsyncIO) • Certified AWS Associate Developer with IaaC mindset. Extensive experience working with AWS and Azure • Hands-on experience with SQL and noSQL databases (AWS DynamoDB, Azure CosmosDB, PostgreSQL) • Comprehensive expertise in backend development: RESTful APIs, GraphQL, Serverless and Event-Driven architectures, SAGA pattern, ACID • ETL (AWS Step Functions, Airflow) • Deep understanding of CI/CD process, knowledge of Docker and DevOps • Solid background in VCS: GitHub, GitLab, BitBucket, AWS CodeCommit • Experienced in managing teams of up to 5 people • Proficient English level: C1. Proven by IELTS certificate Worked with S&P500 companies like: ⭐Microsoft ($211.9B revenue for 2023) ⭐EPAM ($4.7B revenue for 2023) I am an enthusiastic team player understanding the big picture and ready to push myself to the limits. Collaborated within diverse multinational teams comprising professionals from the United States, Australia, Germany, India, and various other countries. Comfortable working with both engineers and management to formulate the necessary steps to make the product a success. Experienced in managing teams of up to 5 people, fostering a positive and productive work environment. This is what clients and team members usually say about me: 📍 "… we would like to give visibility of the praise expressed by the CDSIC and Microsoft team for the impact of the work Aleksei has brought to the project. The team has seen a significant acceleration of progress on the rules validation engine since Aleksei has joined the team.  The Microsoft team describes Aleksei as a fantastic resource that brings confidence to the team.  Thank you for the great work!" - Tianna Umann, Chief Innovation Architect at Microsoft 📍 "Reliable as nails. If I had to pick a developer to go to on a dangerous mission with, he'd be at the top of my list" - Maksim Tsvetovat, Principal at EPAM 📍 "On behalf of CDISC, I am writing to share our sincere appreciation of Alex's contribution. Alex was quick to become an effective contributor to the product. Message queuing, cache scaling, and dataframe preprocessing are a few improvements Alex initiated that became the foundation of our application. We wish Alex all the best under the current hardship, hoping the better will soon emerge" - Anthony Chow, Director of Data Science at CDISC
    Featured Skill Backend Rest API
    Azure App Service
    Architecture
    RESTful API
    Agile Software Development
    GitHub
    AWS Lambda
    Amazon Web Services
    Python
    Redis
    Django
    Azure Cosmos DB
    Flask
    Amazon DynamoDB
    PostgreSQL
  • $45 hourly
    • 5.0/5
    • (20 jobs)
    I design and implement reliable, high-performance platforms — from SaaS solutions to complex backend and AI-driven architectures. 🟢 Backend Engineering – High-performance systems built with Java and Spring Boot. Production-grade experience designing modular monoliths and microservices, with robust data layers and event-driven architectures. 🟢 SaaS Development – Multi-tenant systems with subscription management, admin dashboards, and built-in BI analytics. 🟢 Frontend Development – Responsive, modern UIs built with React and TypeScript. 🟢 Desktop Applications – Cross-platform desktop apps built with JavaFX, often integrated with complex backends and real-time data flows. 🟢 AI/ML Integration – Backend support for AI/ML/LLM-powered features. 🟢 Scraping Solutions – Reliable and scalable web scraping pipelines for structured and unstructured data extraction. 🟢 Cloud Infrastructure – Scalable solutions on AWS or GCP, complete with CI/CD pipelines, robust architecture and full monitoring. 🧩 I'm hands-on throughout the entire process – from understanding requirements and choosing the right tech, to designing the architecture, building the core, testing, and launching the solution. 💬 I stay in regular, open communication with the client to make sure we're always on the same page. That way, I deliver work I'm proud of – and they're happy with.
    Featured Skill Backend Rest API
    Python
    AI Development
    Software Architecture & Design
    DevOps
    Desktop Application
    Web Development
    Apache Kafka
    NoSQL Database
    PostgreSQL
    RESTful API
    Hibernate
    Spring Framework
    Spring Boot
    Java
  • $40 hourly
    • 5.0/5
    • (22 jobs)
    Hi there 👋 Need a reliable expert in WEB software development to build scalable SaaS products? I’m Sergei, a results-driven Full-Stack Developer with over 10 years of experience delivering high-performance solutions for startups and enterprises. 🚀 What I Offer: - Advanced Frontend Development: Angular (2–19), React, Next.js - Robust Backend Solutions: Node.js, Express, NestJS, GraphQL - Database Expertise: MongoDB, PostgreSQL - Cloud & DevOps: AWS, DigitalOcean, Vercel, CI/CD (GitHub Actions, Jenkins) - Testing: Unit and e2e testing for reliable, maintainable code - Architecture & Performance: Scalable, maintainable code optimized for speed and UX 💼 Leadership Experience: - CTO in a Startup: Led tech strategy, secured funding, and grew a product from idea to market - Team Lead: Managed cross-functional teams (10+ people), conducted technical interviews, and mentored developers 🎯 Why Work With Me? - I deliver clean, scalable code that reduces technical debt and accelerates product growth - Proven track record of on-time, budget-friendly project delivery - Transparent communication and a focus on business outcomes Ready to bring your project to life? Let’s connect and discuss how I can help you achieve your goals!
    Featured Skill Backend Rest API
    AI Development
    AI Agent Development
    SCSS
    CSS
    HTML
    Database
    RESTful API
    Front-End Development
    Node.js
    Angular Material
    AngularJS
    JavaScript
    TypeScript
    Angular
  • $30 hourly
    • 5.0/5
    • (12 jobs)
    Hello there! 👋 My name is Mina, and I am a full-stack web developer with a strong background in Java, Spring Boot, web automation, and data scraping. I hold a Master’s degree in Software Engineering and Information Technologies. Since the end of my Bachelor's in 2017, I have been working as a Teaching Assistant in the Informatics Department, where I teach students Java, Spring Boot, and web technologies. Beyond traditional web development, I specialize in web automation and web scraping, particularly for e-commerce platforms. I have worked on projects that involve extracting and analyzing product data from major retailers such as Amazon, Walmart, Best Buy, Costco, and Lenovo. To achieve this, I utilize tools like Selenium (Java & Python), Scrapy, BeautifulSoup, and Requests. Additionally, I have developed price monitoring and comparison systems that track product changes across multiple platforms, integrating features like email alerts, web notifications, and Microsoft Teams API notifications. With a blend of academic and real-world experience, I bring both technical expertise and a passion for problem-solving. I am always eager to collaborate on challenging projects, whether in full-stack development, automation, or data scraping. Looking forward to working on exciting new opportunities! 🚀
    Featured Skill Backend Rest API
    Data Scraping
    Data Mining
    Selenium
    Data Extraction
    RESTful API
    API
    Scrapy
    CSS
    Java
    JavaScript
    MySQL
    Angular
    HTML
    Spring Framework
  • $20 hourly
    • 5.0/5
    • (207 jobs)
    Modern full-stack web apps can transform your business. From streamlining operations to boosting engagement, the right solution unlocks serious potential. But let’s face it, developing and maintaining a robust web platform can feel overwhelming. Between frontend and backend logic, deployment pipelines, user experience, and security concerns... it’s easy to lose valuable time trying to get it all right. That’s where I come in. I'm a full-stack developer with 4+ years of experience building fast, secure, and scalable applications for startups, SaaS businesses, e-commerce platforms, and enterprise teams. Whether you're launching from scratch or modernizing a legacy system, I’ll help you go from idea to fully deployed app—cleanly, efficiently, and without the guesswork. Skills: 👨‍💻4+ Years Experience in Full-Stack Web Development 💡 Passionate about clean code, performance, and creating seamless user experiences 🔹 Programming Languages 🟨 JavaScript (ES6+), TypeScript 🛢️ SQL – MySQL, PostgreSQL 🔹 Front-End Development ⚛️ React.js & React Native – Component-based, high-performance UIs ⚡ Next.js – SSR, SEO, optimized routing, API routes 🎨 Tailwind CSS, Styled Components, Bootstrap, Material UI – Clean, responsive design systems 📊 Redux Toolkit – Scalable state management with code splitting 🎥 GSAP, Framer Motion – Advanced animation and micro-interaction libraries 🧩 React Hook Form + Zod – Scalable form validation and error handling 🌍 react-i18next – Full localization/multi-language support 🔹 Back-End Development 🧠 Node.js & Express – Fast, scalable APIs and server logic 🔗 RESTful & GraphQL API integration 🔐 JWT, Firebase Auth – Secure authentication and user sessions 🗃️ MongoDB, PostgreSQL, MySQL – Structured and NoSQL DBs 📚 Mongoose, Sequelize ORM – Efficient DB modeling 🔹 DevOps & Deployment 📦 Docker – Containerized environments 🌐 Nginx – Web server and reverse proxy configuration 🚀 GitHub Actions – CI/CD automation 🖥️ VPS, Netlify, Vercel, Render – Scalable cloud deployment 🛠️ Git, GitHub, Bitbucket – Version control & collaboration 🔹 Testing & QA 🧪 Jest – Unit testing 🔍 React Testing Library – Component testing I’ve built scalable platforms like Goddess Within, a complete e-commerce system; Melody Mingle, a high-performance music app; and New Horizon, a real estate portal—each deployed in real-world environments with enterprise-level structure. 🌐 andrijadesign.com Let’s chat about your goals and how we can build something great—efficiently, cleanly, and with zero guesswork.
    Featured Skill Backend Rest API
    CSS
    Tailwind CSS
    SaaS Development
    MERN Stack
    Redux
    MongoDB
    TypeScript
    PostgreSQL
    RESTful API
    NestJS
    Node.js
    React Native
    Next.js
    React
    JavaScript
  • $35 hourly
    • 4.5/5
    • (26 jobs)
    I'm your one-stop backend expert for building and deploying fast, reliable, and maintainable systems, using Python, FastAPI, MongoDB, and modern async tooling. Whether you need to: 🔍 Build a fast and scalable query DSL or full text search API 🧠 Refactor/migrate and scale an existing backend 💲 Set up a subscription system and integrate a payment gateway like Stripe ⚙️ Add background processing with Celery or Dramatiq 🔗 Integrate third-party APIs and develop async data pipelines for seamless data exchange 📊 Optimize SQL queries and database performance …I can help you move from bottlenecks to clean, scalable solutions — with CI/CD pipelines, error monitoring, and clear, tested code. Tech I work with: • modern, typed and async Python • FastAPI • Flask • Django • Pydantic • MongoDB • PostgreSQL • Elasticsearch • Redis • Celery • dramatiq • OpenAPI Swagger Specs • Sentry • GitHub Actions CI/CD • Docker • Stripe
    Featured Skill Backend Rest API
    Linux
    Redis
    Celery
    Django
    Docker
    RESTful API
    CI/CD
    Back-End Development
    DevOps
    Python
    Elasticsearch
    MongoDB
    PostgreSQL
    Flask
    FastAPI
  • $55 hourly
    • 4.6/5
    • (72 jobs)
    🌟 Microsoft Power Platform and SharePoint Expert 🌟 Over 5+ Years of Experience 🌟 50+ Successful Projects 🌟 5-Star Reviews Hi, I'm Bojan, a skilled Microsoft Power Platform and SharePoint Developer with over 5 years of experience helping organizations automate their work processes with 50+ custom business management apps. My primary focus is on delivering value to my clients by understanding their needs and providing tailor-made solutions. My expertise includes: ✅ Power Apps Canvas App Development ✅ Power Automate Cloud & Desktop Automation ✅ SharePoint Customization and Integration As a dedicated part-time freelancer, I prioritize clear communication and a client-centric approach. I can assist you with: 🔹 Streamlining business processes and automating manual tasks 🔹 Creating insightful dashboards and reports for data-driven decision-making 🔹 Designing, developing, and implementing custom applications 🔹 Providing expert advice to help you achieve your ideal goals My toolkit includes Microsoft PowerApps, Power Automate, and SharePoint. I am committed to delivering high-quality solutions that exceed expectations and help my clients focus on their core business activities. I pride myself on being responsive, available, and transparent in all my interactions. To maintain a perfect responsiveness score, I promptly reply to invitations and messages, update my profile visibility, and adjust my availability status accordingly. Feel free to contact me to discuss your project requirements and discover how my expertise in Microsoft Power Platform and SharePoint can drive your business success. Let's work together to bring your vision to life!
    Featured Skill Backend Rest API
    Automation
    Microsoft Azure SQL Database
    Microsoft Dynamics Development
    Microsoft Power Automate Administration
    RESTful API
    Microsoft PowerApps
    Microsoft SharePoint
    Microsoft Power Automate
    HTML
    Microsoft Power BI
    Microsoft Dynamics 365
    SOAP
    Microsoft Azure
    C#
    SQL
  • $40 hourly
    • 5.0/5
    • (6 jobs)
    I am a software engineer with a passion for building robust and efficient web applications. My skills include: ⦁ PHP (Laravel, Livewire) ⦁ CSS (Tailwind CSS, Bootstrap) ⦁ JavaScript (Vue.js, Alpine.js, jQuery) ⦁ Databases (MySQL, PostgreSQL, Redis) I have a strong understanding of software engineering principles and best practices, and I enjoy applying these to solve complex problems. My expertise lies in designing and developing robust, scalable, and high-performance web applications using PHP language and Laravel framework. I enjoy solving complex problems, and I'm always looking for ways to improve my skills and stay up-to-date with the latest industry trends and technologies. If you're looking for a skilled software engineer who can deliver high-quality work on time, I'd love to hear from you!
    Featured Skill Backend Rest API
    Tailwind CSS
    Web Application
    RESTful API
    Software Architecture & Design
    Vue.js
    Database
    Custom PHP
    Web Development
    SQL
    PHP
    CSS
    MySQL
    HTML
    API
    JavaScript
  • $75 hourly
    • 5.0/5
    • (20 jobs)
    Hello! I'm a Software Engineering graduate and a dedicated Web Developer with a passion for crafting seamless digital experiences. I specialize in front-end development with strong expertise in HTML, JavaScript (ES6), TypeScript, jQuery, Angular, ReactJS, NextJS, NodeJS, ExpressJS and Git. I'm also experienced in building responsive interfaces using React Bootstrap, CSS/SCSS, Sass, Bootstrap, TailwindCSS, and Material UI. For email development, I bring precision and a keen eye for detail. When it comes to design, I work efficiently with Adobe XD, Photoshop, and Figma to create visually appealing web experiences. With a strong academic background, I'm quick to research and master new technologies, staying on top of the latest trends in web development. I thrive in team settings, easily integrating with development teams and contributing to a collaborative, productive environment. My flexible working hours mean I can adapt to your schedule seamlessly. I'm eager to bring my skills to your project, and I look forward to working with you!
    Featured Skill Backend Rest API
    ExpressJS
    Node.js
    RESTful API
    Next.js
    Responsive Design
    TypeScript
    Web Application
    Bootstrap
    SCSS
    React Bootstrap
    JavaScript
    React
    HTML5
    CSS 3
    SQL
  • $45 hourly
    • 5.0/5
    • (5 jobs)
    If you're seeking a web developer capable of creating engaging web apps, enhancing site performance, expertly handling APIs, streamlining content with Strapi or Django, crafting collaboration platforms, and developing blockchain technologies such as Web3 applications and smart contracts, you've come to the right place. Let's work together to transform your web development obstacles into accomplishments—get in touch to kick-start our journey! When you opt to collaborate with me, you're doing more than just employing a developer. You're establishing a partnership with a committed professional who's dedicated to delivering tangible results. Here's what you can expect from our collaboration: - Superior User Experience: I design web apps that are visually attractive and prioritize user-friendliness, responsiveness, and intuitiveness, resulting in increased user engagement and satisfaction. - Boosted Site Performance: Utilizing the most up-to-date optimization methods, I'll ensure your website loads rapidly, maintains visitor attention, and boosts your SEO ranking. - Smooth Integration: I specialize in integrating third-party or custom-built APIs, thereby expanding your web app's capabilities and enriching the user experience. - Streamlined Content Management: By using Strapi or Django, I'll simplify your content management process, enabling you to effortlessly update and publish content to keep your website relevant and fresh. - Collaboration Platform Creation: I'll design efficient and user-friendly collaboration platforms that will enhance team communication and productivity. - Blockchain Development: With deep expertise in blockchain technology, I can develop Web3 applications and smart contracts, paving the way for decentralized and secure transactions. - Quality Assurance and Reliability: I follow industry-standard coding and testing practices to deliver superior products that consistently surpass expectations. These are not just theoretical promises; they are tangible benefits I've delivered repeatedly to my clients. If these are the results you desire, don't hesitate to send me a message. Let's set the wheels in motion! I offer a comprehensive set of technical skills as a web developer: - Frontend: React.js, Next.js, JavaScript (ES6+) - Backend: Node.js, Express.js, Nest.js, Python, FastAPI, Flask - Databases: PostgreSQL, MySQL, MongoDB, Redis, SQLite, LevelDB - APIs: RESTful, GraphQL, Stripe API, PayPal API - CMS: Strapi, Django - Blockchain: Web3.js, Ethers.js, TronWeb.js, Solidity (Smart Contract development) - Collaboration Platforms: Customized solutions designed for efficiency and user satisfaction. - Testing & Debugging: Jest, Mocha, PyTest, Selenium, Chrome DevTools, Cypress - Deployment & DevOps: AWS, Azure, Heroku, Netlify, Docker, Kubernetes - CI/CD: Github Actions, GitLab Pipelines This diverse tech stack allows me to choose the most effective tools for your specific requirements, ensuring an efficient and effective solution. If you're ready to utilize these skills for your project, drop me a line! In addition to my technical capabilities, I pride myself on being a proactive, reliable team player. I emphasize clear communication, a problem-solving approach, and a steadfast commitment to quality in all of my projects. I'm flexible with availability and open to both long-term contracts and standalone projects. Regardless of your project's size or complexity, I'm prepared to jump in and make a difference. Interested? Want to discuss your project or chat about potential collaborations? I welcome you to send me a message. Let's explore how we can turn your web development goals into a reality!
    Featured Skill Backend Rest API
    web3.js
    MongoDB
    Flask
    Django
    Python
    Bot Development
    CSS 3
    Docker
    RESTful API
    TypeScript
    Next.js
    Node.js
    ExpressJS
    RabbitMQ
    React
  • $35 hourly
    • 4.7/5
    • (3 jobs)
    Hello! I am a Full-Stack Web Developer with 7+ yrs of experience in Building Scalable and Responsive Web and Mobile Apps with ReactJS, React Native, PHP Laravel, Node.js, Python I have strong skills in both front-end and back-end web development. I use HTML, CSS, JavaScript and ReactJS, VueJS, Angular for the front-end, and PHP Laravel, Node.js, Python for the back-end. I also use React Native for building cross-platform mobile apps. I am proficient in using databases such as MySQL, PostgreSQL and MongoDB, as well as APIs and web services My skill set includes: - React.js, Next.js, Angular, Vue.js, Nuxt.js, Redux, Vuex - React Native - Tailwind CSS, Bootstrap UI, Material UI - Node.js, Nest.js, express.js - PHP Laravel, Nova, Livewire, Alpine.js - Python, Django - Micro Service, REST API, GraphQL, Apollo Client - MySQL, PostgreSQL, MongoDB, Apache Casandra - Docker - AWS, Google Firebase, Supabase If you are looking for a reliable and creative full-stack web developer who can turn your ideas into reality, look no further. I am ready to start working on your project today. Just send me a message or invite me to your job and let's get started!
    Featured Skill Backend Rest API
    Next.js
    Vue.js
    RESTful API
    NestJS
    Laravel
    Python
    TypeScript
    JavaScript
    GraphQL
    PostgreSQL
    React Native
    React
    MySQL
    Node.js
    Angular
  • $50 hourly
    • 4.9/5
    • (93 jobs)
    🔊 Vibe Programming available 💻 Programming Languages 🟣 C# | 🔵 VB.NET | 🟢 SQL | 🟡 JavaScript/TypeScript | 🟠 Node.js ☁ Cloud Platforms 🔹 Azure: AppService, Functions, ServiceBus, CI/CD (GitHub Actions), CosmosDB, VM 🔹 AWS: Lambda, DynamoDB, EC2 (VM) 🔹 Google Cloud: Firebase 🏗 ORM & Data Access 🟢 Entity Framework | 🔵 Dapper | 🔸 ADO.NET | 🟠 LINQ 🌐 Backend Development ✔ ASP.NET Web Forms/MVC | ✔ Web API | ✔ SignalR ✔ Blazor (Server & WebAssembly) | ✔ MAUI ✔ WCF Data Services | ✔ IdentityServer/Duende | ✔ Keycloak ✔ MediatR (CQRS & Request/Response Patterns) ✔ Node.js (Express, Fastify, NestJS, WebSockets, WebRTC) 🎨 Frontend & UI Technologies 🔹 React | React Native 🔹 AngularJS 1.5+ / Angular 2+ 🔹 jQuery | Bootstrap 3,4,5 | Material Design 🔹 WebRTC (Real-time Audio/Video Communication) 📱 Mobile & Hybrid Development 🔹 Ionic | NativeScript | Xamarin | MAUI | React Native 🖥 Desktop Development 🔹 WPF | WinForms | UWP | MAUI 🗄 Database & Data Storage 🔹 Relational Databases: MS SQL Server (2000 - 2016) | PostgreSQL | SQLite | Oracle (9i, 10i, 11i) | MS Access | MySQL 🔹 NoSQL & Vector Databases: MongoDB | RavenDB | Firebase Firestore Elasticsearch (Full-text search) | Qdrant | Pinecone (Vector Search & AI-based Retrieval) 🏢 Operating Systems 💠 Windows | 💠 Unix/Linux 🚀 Frameworks & Architecture 🔹 .NET Framework 2.0 - 4.8 | .NET Core 3+ 🔹 Blazor (Server & WebAssembly) | MAUI 🔹 Node.js (Express, Fastify, NestJS) 🔹 IdentityServer/Duende, Keycloak 🔹 MediatR (CQRS, Request/Response & Notification Handlers) 🔹 UnitOfWork & Repository Pattern 🔹 Async/Parallel Execution 🤖 AI & Machine Learning 🟠 OpenAI (GPT, Codex, DALL·E, etc.) 🟣 Ollama (Fine-tuning & RAG) 🟢 ML.NET (Machine Learning for .NET) 🔵 ONNX Runtime (Optimized AI Model Inference for .NET) 🔥 Why Work With Me? ✅ Over 15 years of hands-on experience in multi-tier development, relational databases and business applications. ✅ Extensive experience in HR, GIS, Medical, Real Estate, GPS Tracking, Ecommerce and Commercial Software Development. ✅ Strong expertise in web applications, including REST/OData, GraphQL, SOAP/XML services. ✅ Advanced database design skills, including complex SQL queries, stored procedures and performance tuning. ✅ Strong network administration background (MCSA Certified). ✅ Excellent analytical skills, adaptable to evolving technical environments. ✅ Proficient in front-end, back-end, cloud, AI, real-time communication (WebRTC) and DevOps, ensuring end-to-end software development expertise. 📩 Let’s Connect! 🚀 Looking for a reliable full-stack .NET & Node.js developer to elevate your business? Let's talk!
    Featured Skill Backend Rest API
    AI Development
    AI Chatbot
    .NET Core
    JavaScript
    ASP.NET Web API
    Websockets
    Angular
    OAuth
    Google Maps API
    MongoDB
    C#
    Visual Basic
    SQL
    RESTful API
    ASP.NET Core
  • $70 hourly
    • 4.9/5
    • (7 jobs)
    Worked on many projects from scratch and with big projects already in production. Let my past work speak for itself: 1. gemnote.com (Ruby/Rails, HTML, CSS, Javascript (Angular 1.x), Stripe, Rest API) 2. zephr.com (Ruby/Rails, CSS, HTML, Javascript, Zoom API) 3. shoobs.com (Ruby/Rails, CSS, HTML, Javascript, Stripe) 4. bidsketch.com (ReactJS, Redux) 5. reefer.com (Ruby/Rails, CSS, HTML, Javascript, Stripe) 6. Orca (Javascript (Electron, VueJS), HTML, CSS, FIrebase, Social networks integration) 7. namastream.com (Ruby/Rails, HTML, CSS, Javascript, Angular 1.x) 8. protonet.com (Ruby/Rails, HTML, CSS, Rest API, Linux system, Microsoft Azure, Redis, RabitMQ) 9. findrow.com (Ruby/Rails API, HTML, CSS, ReactJS/NextJS (mobx, mobx state tree)) 10. dps.aki.do (NodeJS, ReactJS/NextJS, HTML, CSS) 11. frankforall.com (Ruby/Rails API, ReactJS/NextJS (mobx, mobx state tree), OpenPay API, React Native (Android & iOS)) 12. phixst.com (Ruby/Rails API, Stripe) ... And many more...
    Featured Skill Backend Rest API
    Mobx
    Electron
    RSpec
    Performance Optimization
    Redux
    Database Architecture
    RESTful API
    CSS 3
    React
    Ruby on Rails
    Ruby
    JavaScript
    Vue.js
  • $35 hourly
    • 4.8/5
    • (119 jobs)
    responsible and very ambitious, highly dedicated to his work and on a constant quest for new, innovative solutions and ideas. Iinterested in programming and a logical approach to problem solving. Code perfectionist in the best sense of the word. Above all, I am a team player, who developed an understanding of fair play and team spirit through participation in numerous sports activities.
    Featured Skill Backend Rest API
    MVC Framework
    Payment Functionality
    jQuery UI
    RESTful API
    Laravel
    SaaS
    PHP
    CodeIgniter
    Web Application
    Vue.js
    Bootstrap
    AJAX
    API Integration
    MySQL
    HTML5
  • $60 hourly
    • 5.0/5
    • (14 jobs)
    -5 years of experience as back-end Java developer -Neo4j Certified Professional - Worked on several Java projects. - Comfortable with Spring, Tomcat and Vertx frameworks -Worked with PostgreSQL, MySQL and Neo4j graph database. -Worked with Docker, Git -Worked with aws: ec2,s3, lambda -Worked with Sellenium and Jenkins for testing purpose. -Worked with iaik and bouncyCastle security libraries -Worked with Thales HSM hardware. -Created scripts in bash and python. -Good knowledge of English -Excellent problem-solving skills -Strong analytical skills -Quick learner -Eager to learn new technologies. -Able to work under pressure and tight schedule
    Featured Skill Backend Rest API
    Apache Kafka
    Elasticsearch
    API
    RESTful API
    Vert.x
    Spring MVC
    Python Script
    Bash Programming
    Neo4j
    Java
    PostgreSQL
    MySQL
  • $150 hourly
    • 5.0/5
    • (27 jobs)
    I'm a full stack Developer with 10 years of work experience, currently living in Belgrade, Serbia. For the last 5 years my go to stack is Laravel, Vue.js (lately Nuxt.js), Python (for specialized tasks) and Nginx - and i've been using it for kinds of projects. From medical SAAS, statistical analysis APIs to micro services. In the past, I've worked with clients from all over the world(mostly New York) and for stock markets like Envato.
    Featured Skill Backend Rest API
    HIPAA
    Vuex
    RESTful API
    Laravel
    Nuxt.js
    Twilio API
    SCSS
    Vue.js
  • $50 hourly
    • 5.0/5
    • (71 jobs)
    I can take care of all the aspects of your project - from concept to deployment. Aside from coding, I can advice you whom to hire and what to look for to save money and improve quality. I will not suggest you a technology just because it's cool. I will work with you to figure out what's best for your wallet, your business and your customers. Get in touch and we can discuss!
    Featured Skill Backend Rest API
    Web Application
    Ruby on Rails
    jQuery
    Database Architecture
    Software Architecture & Design
    React
    RESTful API
    PostgreSQL
    API
    Sass
    TypeScript
    Ruby
    Web Development
    JavaScript
    SQL
    API Integration
  • $50 hourly
    • 5.0/5
    • (37 jobs)
    Full Stack Developer with a variety of skills, specializing in Python, Vue.js and AWS. I have a strong business and engineering background and can quickly turn requirements into professional results. I am comfortable with architecting and implementing scalable and maintainable web apps/services. I specialize in backend development, database design and architecture, cloud architecture, Unix server management, API development and integration. I have over 10 years of backend development experience under my belt, for companies, individual clients and my personal pet projects. 💻 My Core Tech: - Full-stack development with MVC architecture - Back-End Frameworks (Django, Celery, Django Channels Websocket) - Front-End Frameworks (Vue.js) - Automation, scraping, management scripting (Scrapy, Request, AsyncIO, Pydantic) - API development (Django RESTFul API) - Strong database management skills (PostgreSQL, MySQL, MongoDB, Redis) - Continuous Integration (Git, Bitbucket) - AWS solutions (EC2, S3, Elastic beanstalk). Thanks!
    Featured Skill Backend Rest API
    Python Asyncio
    Vue.js
    Celery
    RESTful API
    Django
    Docker
    Data Science
    Data Mining
    Automation
    Machine Learning
    Python
  • $50 hourly
    • 5.0/5
    • (25 jobs)
    Need a reliable, well-designed and secure software built? I am a highly skilled back-end engineer, with over 8 years of experience, with strong attention to code quality and best security practices. Having experience with small-to-medium sized companies, my own startup, I understand the various stages of software and business development, and enjoy working on challenging projects. If you think we would be a great team, send me a message, and let's discuss making your ideas live. :)
    Featured Skill Backend Rest API
    Web Application
    Payment Gateway Integration
    Linux System Administration
    API Integration
    Software Architecture & Design
    RESTful API
    Database Design
    MongoDB
    NGINX
    Python
    Redis
    Django
    PostgreSQL
  • $25 hourly
    • 5.0/5
    • (3 jobs)
    I'm Ivan, an Android Developer with over 6 years of experience. I am proficient with writing code in Java and Kotlin and have an excellent understanding of OOP and SOLID principles. SQL database, MVVM and Clean architecture, GIT (GitHub, Bitbucket), Jetpack Compose, Dependency Injection, Develop applications that use RESTful APIs to connect to back-end services, Develop layouts for different screen sizes, Jira & Zeplin tools, Gradle, and Code refactoring. Publishing apps on Google Play store, Galaxy Store & App Store. Monetizing apps with AdMob ads and In-App purchases. Working with 3rd party libraries (Dagger + Hilt, Retrofit, Room, Volley, iText, Ffmpeg, OneSignal, Firebase, Picasso, Glide, Google Maps, GSON, Crashlytics, Firebase Cloud Messaging, Admob, CameraX, Coil, etc.). Basics usage of HTML5, CSS3, and JavaScript coding practices. Advanced problem-solving skills. ADDITIONAL SKILLS - Basic knowledge of iOS app development (Xcode – Swift 5 language) - Build and publish iOS applications in the App Store. Monetizing with AdMob ads - 3rd party libraries (Firebase Authentication and Realtime Database, PDFKit, Admob, etc.) - Beginner in a flutter - Adobe Photoshop & Adobe Illustrator LANGUAGE - English - Serbian
    Featured Skill Backend Rest API
    Android UI Design
    Flutter
    Android App
    Kotlin
    Gradle
    JetPack
    Android SDK
    Android App Development
    Android Studio
    GitHub
    JSON
    Git
    RESTful API
    Java
    XML
  • $20 hourly
    • 5.0/5
    • (3 jobs)
    I’m a backend developer with 5+ years of experience working in a high-paced environment, focusing on building reliable data pipelines and monitoring solutions. I previously worked at a major quant firm, developing and maintaining critical infrastructure for data processing and system observability. I’ve also built a complete data pipeline and software solution for an accounting company, streamlining their workflow and automation. Now, after relocating, I’m back to freelancing and open to new projects. Expertise: ✅ Backend development with Node.js ✅ Designing and optimizing data pipelines ✅ Building scalable APIs and microservices ✅ System monitoring, alerting, and automation ✅ Database architecture (SQL & NoSQL) ✅ Cloud infrastructure & serverless solutions ✅ Frontend development with React & Vue I thrive on solving complex problems with structured, pragmatic solutions. I value clear communication, efficient execution, and delivering quality work within realistic deadlines. Let’s build something great together.
    Featured Skill Backend Rest API
    Functional Programming
    Jest
    Data Scraping
    Data Collection
    Web Scraping
    DevOps
    RESTful API
    Kubernetes
    PostgreSQL
    API Integration
    Node.js
  • $35 hourly
    • 0.0/5
    • (0 jobs)
    Welcome to my profile! I am a Serbia based full stack software developer specializing in providing high-quality web and machine learning development. For 5 years, I have been working on web applications, Machine learning development, Matlab and etc with many clients. I provide good and perfect quality of work and finish project until customer is 105% satisfied. My main goal is to build good relationship with customers and launch my own software company. Let's talk about your project! Thanks Lazar
    Featured Skill Backend Rest API
    RESTful API
    WordPress
    React
    Django
    Shopify
    Python
    MATLAB
  • $45 hourly
    • 0.0/5
    • (1 job)
    Expert in Python and Django development. Proficient in setting up CI/CD pipeline with Travis/CircleCI or similar. Have good knowledge of AWS infrastructure. Long term jobs only, please.
    Featured Skill Backend Rest API
    RESTful API
    Travis CI
    CircleCI
    Django
    DevOps
    React
    Python
    Amazon Web Services
  • $15 hourly
    • 4.9/5
    • (15 jobs)
    Experienced in .NET and ReactJS, NextJS, Flutter, with experience with RestAPIs, Websockets. I have over 5 years in .NET and years on the frontend and flutter. I also have experince with relational databases and connecting them with the backend. Thanks for cheking out my profile, looking forward to working with you Luka.
    Featured Skill Backend Rest API
    CSS
    Windows App Development
    Android
    Sass
    RESTful API
    HTML
    SQL
    Web Application
    React
    Windows API Development
    Windows Forms
    Windows Presentation Foundation
    .NET Framework
    C#
    JavaScript
    Microsoft Visual Studio
  • $20 hourly
    • 5.0/5
    • (3 jobs)
    As a skilled Frontend Developer, I bring extensive experience in delivering high-quality, large-scale projects for international clients. I specialize in crafting pixel-perfect, highly optimized, and accessible web solutions that prioritize both performance and user experience. My expertise spans a wide range of modern technologies, including HTML, CSS, JavaScript, React, Next.js, RESTful APIs, and SEO best practices. I thrive on solving complex challenges, continually refining my skills to stay at the forefront of industry standards. What you can expect from me: - Pixel-perfect design implementation aligned with your vision. - Optimized and accessible code that ensures excellent performance. - Professional communication to ensure smooth collaboration and project success. I believe every successful project starts with clear and effective communication. If you're looking for a developer who is passionate about delivering top-tier results, let’s connect to discuss your project needs.
    Featured Skill Backend Rest API
    Communications
    SCSS
    Web Accessibility
    Performance Optimization
    Web Development
    Responsive Design
    Front-End Development
    RESTful API
    JavaScript
    TypeScript
    CSS 3
    HTML5
    React
    Next.js
  • $20 hourly
    • 5.0/5
    • (1 job)
    I am a proficient Engineering Manager and Solutions Architect with extensive experience in Agile Leadership. My expertise lies in optimizing project workflows and establishing high-quality technical and organisational solutions that align with business objectives. Key Skills and Expertise: - System Architecture and Design: With a strong background in designing large-scale systems, including microservice architectures and multi-database cloud environments (AWS, GCP, Azure) , I deliver robust and scalable solutions tailored to your needs. - Fullstack Development: Over 8 years of experience in frontend development (React, Angular, AngularJS, VueJS and others), backend development (Spring Framework, Python, NodeJs, PHP), ensuring comprehensive technical oversight and implementation - Technical Project Management: Experienced in breaking down complex projects into manageable tasks, ensuring alignment with business goals and seamless execution - Team Organization and Optimization: Proven track record of organizing and leading efficient teams, enhancing productivity, and ensuring optimal performance through effective team management and process optimization. - Agile Leadership: Certified Scrum Master adept at fostering collaboration, streamlining workflows, and driving agile transformations. I excel in leading cross-functional teams to deliver projects on time and within scope. 🎖️If you're seeking a skilled Technical Project Manager who can deliver exceptional technical solutions and optimize processes, let's discuss your project, I would be glad to contribute to your success! Together, we can achieve your goals efficiently and effectively.
    Featured Skill Backend Rest API
    Cloud Architecture
    Spring Framework
    Angular
    RESTful API
    Cloud Computing
    AngularJS
    Architecture
    Back-End Development
    Agile Software Development
    Java
    Amazon Web Services
    Docker
  • $55 hourly
    • 0.0/5
    • (0 jobs)
    I am a senior software engineer with ten years of rich and diverse experience in different technologies, gained by participating in numerous projects and cooperating with wide range of international clients. I am always in search of new knowledge, challenging projects, and interesting and innovative business ideas. My greatest advantage is very broad knowledge and understanding of various technologies and systems. This provides me the ability to fully perceive and understand project requirements and scope, lead projects and perform all tasks from start to finish independently, and successfully predict and overcome potential problems in advance. As a full stack software engineer, my specialties are: Backend: C#, Microsoft .NET Frontend: Angular, TypeScript/JavaScript, HTML, CSS Database: Basically any widely used SQL database (Microsoft SQL Server, Oracle, PostgreSQL, MySQL etc.)
    Featured Skill Backend Rest API
    Microsoft SQL Server
    .NET Core
    RESTful API
    Linux
    Microsoft Visual Studio
    Oracle Database
    C#
    Microsoft Azure
    Azure DevOps Server
    TypeScript
    JavaScript
    HTML
    Angular
    .NET Framework
    CSS
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