Hire the best Backend Rest API Freelancers in Warsaw, PL

Check out Backend Rest API Freelancers in Warsaw, PL with the skills you need for your next job.
  • $40 hourly
    Software Engineer with over 3 years of experience🚀Python | Web apps | ETL Pipelines | Chatbots ✅Hire me if you want to talk Tech in Business language. 📌You want to set up a new project? I will propose the best technology stack and Architecture! 📌You have an ongoing project? I will quickly fit in and do my best to support the team and Business goals! 📌You want to refactor your code? I will do a safe transition and make sure nothing is left behind! 💪More about my skills that will help us achieve the best result: ✅Test Driven Development & Domain Driven Design ✅FastAPI, Django/DRF, Flask, Celery, SQLAlchemy ✅Numpy/Pandas, Apache Spark, Apache Airflow ✅ SQLite, MySQL, Microsoft SQL, PostgreSQL, Alembic; ✅ NoSQL - MongoDB, Redis, Elasticsearch; ✅ AWS, Kubernetes 👨‍💻Even more facts about me! 🔸I do tech talks 🔸I held company hiring events 🔸Reach out to know more!
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Python Asyncio
    Linux
    Flask
    Docker
    PostgreSQL
    Beautiful Soup
    GitHub
    NoSQL Database
    RESTful API
    Django
    SQL
    Git
    Telegram API
    MongoDB
    Python
  • $56 hourly
    Upwork Top 5%. Are you looking for a detail-oriented and meticulous Frontend developer? If so, you are at the right place! Here is what my clients think about me: 💬 "Firdavs was a pleasure to work with, the work was done efficiently and to a great standard. Would definitely work with him again, he is responsible and gets back quickly" 💬 "He’s quick, resilient and technically sound. Felt like we were working with someone from our team. Always available and top-notch work." Key Facts: ✔️ Worked and completed over 100 projects; ✔️ Have plugins and custom themes for sale in marketplaces; ✔️ Expert in Javascript frameworks (React JS/ React Native) ✔️ Over 3 years of solid coding experience. Do you need to build Progressive Web Apps or Single-page applications? I am here to help you! Few things that I can do: ✔️ Creating UI with Next.js and React js; ✔️ Redux, Firebase, Sanity.io, Stripe, Prismic, and other great tools; ✔️ React-router, Material UI, Styled-components, Tailwind; ✔️ Single page applications, Progressive web applications; I can offer you: ✔️ Pixel-perfect web pages ✔️ Building UI with SPAs ✔️ Building whole CRMs from scratch ✔️ Architecturing the whole structure of the website from scratch ✔️ Refactoring old websites and making improvements on the existing applications/projects I achieve high-quality products with a proven software development process. Take a look at my profile and, let's chat!
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Business with 1-9 Employees
    HTML
    API
    HTML5
    XHTML
    Material UI
    PSD to HTML
    JSON
    Bootstrap
    Git
    React
    RESTful API
    web3.js
    CSS
    JavaScript
  • $45 hourly
    ★ Skill in Full Stack Dev - AWS Amplify, AWS Lambda, AWS CloudFormation, Serverless - HTML, CSS, SCSS, Pure JavaScript - JavaScript, Node.js, React, Next.js - PHP, Laravel, WordPress, WordPress plugins - Python, Django, Flask ★ Skill in DevOps - AWS Web Services ( AWS EC2 instance, AWS Lambda, AWS Amplify, AWS Elastic Search, AWS S3, AWS DynamoDB ) - Heroku, Oracle Cloud Infrastructure - Terraform, Docker, Kubernetes, Jenkins ★ Familiar with Databases - MySQL, PostgreSQL, MongoDB, InfluxDB, Oracle ★ Project Management Tools: - GitHub, GitLab, Trello, JIRA, Asana, Basecamp, ClickUp, Zoho, MS Teams, Slack, SVN High quality & Meeting deadline is my goal. Thank you for considering my profile.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Amazon Cognito
    Serverless Stack
    API
    AWS Lambda
    RESTful API
    Laravel
    API Integration
    TypeScript
    JavaScript
    Next.js
    Django
    React
    Python
    Node.js
    Amazon Web Services
  • $45 hourly
    Greetings! 🏆 100% Job Success | ⌛500+ hours on UpWork | 💎 Top Rated Plus Freelancer 👨🏻‍💻 7+ years of experience | Senior Front-End Engineer ⭐ Expert: Next.js | React.js | JavaScript | TailwindCSS | HTML | CSS ✅ Daily updates, ✅ Flexible Availability, ✅ Highest-Quality deliverables ⭐ What I can bring to your project ⭐ ✅ Website or Complex Web Application Development ✅ Top-notch knowledge of React, JavaScript, TypeScript, Redux ✅ Advanced understanding of UI Architectures and what works best for your project ✅ Optimization techniques for efficiently solving bottlenecks in your project ✅ Extensive experience with building Complex UI Solutions and Web Applications ✅ Clean code that conforms to best engineering practices ✅ Ability to quickly diagnose existing code bases and find ways to improve them ✅ You will always be aware of the project status with the help of my task management tools ⭐ Why you should choose me over other freelancers ⭐ ✅ Trust: I'm always transparent about my processes ✅ Ownership: I focus on providing value to your business and maintain impeccable agreements ✅ WOW Factor: this is core to my work as a freelancer. I strive to give more than what I receive to ultimately make you happy about working with me and choosing to hire me again ✅ Problem-solver: I never give up until I find a good solution. I solve problems. ✅ Genuine: I'm rooting for your success. It makes both human and business sense - knowing I've helped you succeed, you'll return to purchase more of my services! ✅ Someone who cares about helping you succeed and bringing value to your business But don't just take my word for it: ⭐⭐⭐⭐⭐ ”Nikita is an outstanding full-stack engineer and easily one of the top front-end engineers I've worked with. Here are a few things to call out: - very sharp front-end architecture skills - incredibly high level of ownership - great product sense Our entire team loved working with Nikita, from design to support.” ⭐⭐⭐⭐⭐ ”Nikita was a standout member of our team during his tenure. He took ownership of his work to a whole new level, always going the extra mile to ensure our projects' success. It was clear that he deeply cared about the company and the product, and his dedication showed in the quality of his work. Nikita had a strong grasp of front-end infrastructure, and his technical knowledge was impressive. He kept up with the latest developments in the field and used that knowledge to come up with practical and innovative solutions that benefited our team and clients…” 💻 FRONT-END SKILLS ⭐ Next.js | React ⭐ Redux | Redux Saga ⭐ TypeScript | JavaScript ⭐ HTML | CSS | SCSS ⭐ Jest | React Testing Library ⭐ Webpack ⭐ Babel ⭐ Eslint | Prettier 🧩 UI | COMPONENTS: ⭐ TailwindCSS ⭐ Ant Design ⭐ Material UI ⭐ Styled Components ⭐ HighCharts 🎭 ANIMATION ⭐ Framer Motion ⭐ React Three | Three.js 📶 INTEGRATIONS ⭐ Stripe ⭐ Auth0 ⭐ Google Auth ⭐ Segment ⭐ Headway 📐 UI ARCHITECTURE & DESIGN ⭐ Feature-Sliced Design ⭐ Atomic Design 🏁 PAGE SPEED OPTIMIZATION ⭐ Lighthouse ⭐ GMetrix ⭐ Profiler 💻 BACK-END SKILLS: ⭐ Node.js | Express.js ⭐ MongoDB | PostgreSQL ⭐ Mongoose ⭐ REST API ⭐ Docker 🆕 READY TO GET STARTED? NEXT STEPS: 1. Invite me to your job 2. I will send my proposal 3. We'll iron out all the requirements and expectations 4. I'll get the work done professionally to ensure you love the result 5. You'll leave an awesome review at the end 😎
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Website Optimization
    TypeScript
    Next.js
    Tailwind CSS
    Web Development
    Material UI
    CSS 3
    Web Application
    JavaScript
    Front-End Development
    HTML5
    React
    Redux
    RESTful API
  • $45 hourly
    8+ years experienced Salesforce Expert within different areas: E-commerce, Real Estate, Financial, Insurance, HealthCare, Energy, and Data Analysis. - Lightning Web Components - Apex - Experience Cloud - Service Cloud - Sales Cloud - Salesforce Setup and Tailoring - Visualforce - Lightning Aura Framework - API integrations (Make.com | Stripe | Intercom | Paypal | E-com platforms & online stores) - Marketing Cloud (Email management) - Java Script, CSS, HTML - Platform Events, Lightning Message Service - Flows, Workflows, Process Builders - Data management (Import & Export as CSV | JSON ) CI/CD: - Git, Bitbucket - Conga - Heroku - Azure - Salesforce Change Sets Certified Salesforce Developer: 1. Salesforce Platform Developer I 2. Salesforce Platform Developer II 3. Security & Privacy Accredited Specialist 4. Marketing Cloud Email Specialist 5. Marketing Cloud Admin
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Angular
    RESTful API
    Visualforce
    Salesforce Lightning
    Salesforce CRM
    React Native
    Omnichannel Automation
    React
    JavaScript
    Apex
  • $99 hourly
    Hello! I am an expert Back-end Developer specializing in FastAPI and Hasura, along with PostgreSQL, MySQL, and MongoDB. My contributions to open-source code include NASA, Tensorflow, Meshtastic, and Python. My job is to turn your awesome ideas into reality as quickly as possible while keeping the backend perfect and the end product stable. I help people build their dream services and solve the problems they encounter with state-of-the-art solutions. Over the last 12 years, I have acquired extensive experience using a variety of languages to craft beautiful back-end systems, along with providing novel solutions, speed optimization, and cloud architecture, ensuring that it can scale globally. I have led the back-end development of ReskyuMe, PaGaLGuY, Easio, and Airbnb amongst many others. An extremely high level of reliability and responsibility is my guarantee, which is evident from all of my reviews being rated 5 stars! I have a deep knowledge of different architectures like x86 and ARM, which allows me to fully understand how different CPUs work, how memory is accessed, and how SIMD/vectorization can be exploited to speed up services. Technologies I use: ✅Languages: C, C++, Python, HTML, CSS, JavaScript ✅Frameworks: FastAPI, Hasura ✅Server Interfaces: REST, GraphQL, Websockets ✅DB Interfaces: SQLAlchemy, SQLModel, PyMongo ✅SQL DBs: PostgreSQL, MySQL, and other SQL-based DBs ✅NoSQL DBs: MongoDB, Cassandra, ScyllaDB ✅Version Control: Git & Mercurial ✅DevOps: Traefik, Nginx, Docker, Kubernetes, Apache, AWS, Google Cloud Platform, Microsoft Azure, Digital Ocean, GitHub Actions ✅Project Management: ClickUp, Trello, Github ✅Operating Sytems: Windows, Linux (Ubuntu, Debian, CentOS, etc.), macOS ✅Cloud Platforms: Amazon Web Services, Google Cloud Platform, Microsoft Azure, DigitalOcean, Linode, Hostinger, et al ✅Cloud Services: Cloudflare ✅LLMs: ChatGPT and self-hosted ones Vast knowledge of: ✅Software design and development ✅Different hardware platforms: x86 and ARM ✅Parallel processing: SIMD and Vectorization ✅Cloud Architecture, CI/CD ✅SQL query construction ✅NoSQL query construction ✅Object-Oriented Programming ✅Speed optimization ✅Usability ✅Security
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Cloud Engineering
    Cloud Architecture
    Cloudflare
    SQLAlchemy
    Object-Oriented Programming
    Database Optimization
    Performance Optimization
    Multithreaded, Parallel, & Distributed Programming Language
    Azure DevOps
    Docker
    RESTful API
    MySQL
    GraphQL
    PostgreSQL
    Python
  • $70 hourly
    🌟 Lead Software Engineer & Data Scientist | Tech Startup Specialist 🎓 MSc Computer Science 🚀 9+ Years Elevating Tech Startups with Advanced Full Stack Development & Data Science At the forefront of tech innovation, I specialize in endless product development, bringing unmatched expertise to robust, scalable solutions. My career spans a series of groundbreaking startups, contributing to multimillion-dollar success stories. My business experience perfectly complement my technical skills, enabling me to align software development with core business goals, market analysis, and efficient team management. 🔑 Core Strengths: * Advanced skills in FastAPI for top-tier API design. * Mastery in data mining and automation with Playwright and Selenium * Deep knowledge in distributed systems, including Kafka and microservices architectures. * Proven excellence in AI and ML, with expertise in TensorFlow and PyTorch. * Proficiency in Cloud Computing with AWS, Azure, DigitalOcean, and GCP. * Expertise in containerization with Docker and Kubernetes (k8s). * Strong knowledge in cybersecurity, ethical hacking, and penetration testing. ✅ Full Stack Development: - Languages: Python, JavaScript, TypeScript, Java, C/C++, Bash; - Python Web Frameworks: FastAPI, Flask, Django, CherryPy, Falcon, Django rest framework, Tornado; - Node.js Web Frameworks: Express.js, Koa.js, Socket.io, Feather.js, Sails.js, Nest.js; - Front-end: React.js, Vue.js; - Databases: MongoDB (GridFS), PostgreSQL, MySQL, MariaDB, Redis, Neo4j, NoSQL; - ORMs: SQLAlchemy, Mongoengine, Marshmallow, Sequelize.js, Mongoose, Prisma; - AMQ: Celery, RabbitMQ; - CI/CD: Docker, docker-compose, kubernetes (k8s); - Deployment: GCP, AWS, MS Azure, DigitalOcean; - SSO: AWS Cognito / Amplify, Auth0, Okta, OneLogin, ORY.sh; - OAuth2.0 OpenID Connect and role management policies: RBAC, ACL, ACP, IAM. 📈 Business Impact: * Contributed to multinational projects for Coca-Cola, Unilever, Sberbank, Bankcolombia, Wargaming; * Recognized in international tech forums, including IAB and Web Summit; 📦 Technical skills: Node.js, Python, Javascript, TypeScript, Java, GoLang, Git, RESTful API, GraphQL, MERN, ES5, ES6, Express, Koa, Feather.js, Sails.js, MongoDB, Redis, DynamoDB, Kafka, MySQL, PostgreSQL, MariaDB, Neo4j, Flask, Django, Selenium, Scrapy, React, React Native, Redux, Vue.js, Webpack, Gulp, Grunt, Pandas, Tensorflow, Keras, NumPy, Docker, Docker-compose, Kubernetes, k8s, Jenkins, Google Cloud Platform, AWS, Microsoft Azure, Cognito, Auth0, Okta, Dialogflow, RASA, Segment, Google Tag Manager, Facebook Pixel, JWT, SQLite, Peewee.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Web Scraping
    Selenium
    Amazon Cognito
    Back-End Development
    Troubleshooting
    Spreadsheet Software
    Data Analysis
    Chatbot Development
    RESTful API
    Automatic Speech Recognition
    Full-Stack Development
    Node.js
    Python
    Data Science
    GraphQL
  • $50 hourly
    I have experience in developing complex web applications and creating production environments for them using infrastructure as code. In developing web applications I usually use python and js. I worked with frameworks: Django, Flask, Fast API, Vuejs, React and etc. I use cloud technologies such as AWS, Azure, GCP for product release and testing environments. For configuration I use tools: CloudFormation, Terraform, aws cli, gcloud cli and etc. Also I would like to mention the experience in creating pipelines for building and continuous delivery of code to different environments. I have experience with CI/CD tools like Jenkins, Gitlab CI, Github Actions, Circle CI.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    DevOps
    Vue.js
    Amazon Web Services
    Terraform
    Ansible
    Python
    Docker
    RESTful API
    Django
  • $35 hourly
    Hello👋 Are you looking for experienced and certified Java engineers to boost your project? You are on the right page! Clear Solutions team provides Java engineers and grows their skills for you. We have more than 12 years of experience in IT and 8+ in Java. My team and I are happy to provide: 🚀 Java developers with transparent knowledge for transparent rates 🚀 People development services: technical assessments, mentoring, evaluation etc. Based on more than 500 interviews and technical assessments we made in the industry so far we created our own evaluation scale. Therefore you always know what set of knowledge you pay for each grade. Do you feel this is what you need? Let's schedule a quick call and find out how we could help you to grow ✅ I have an experience in the following: 👉 migration from on prem to AWS 👉 building microservce architecture from scratch 👉 delivering robust and high-quality code with unit tests 👉 building java high-load and distributed applications 👉 migration from monolith to microservices 👉 building the right engineering culture inside the company 👉 mentoring technical leaders Tech Stack: 🔹 Languages: Java 8, Java 16, Groovy. Spring boot, RESTful API, DB design, 🔸 Frameworks: Spring, Spring Boot, Hibernate, Spring Data 🔹 Clouds: AWS 🔸 SQL: PostgreSQL, MariaDB, Oracle 🔹 NoSQL: Elasticsearch, Redis, MongoDB, Cassandra, DynamoDB 🔸 Message brockers: Apache Kafka or RabbitMQ 🔹 Testing: Junit5, Testcontainers, Spock, RestAssured We have expertise in the following fields: ✅ FinTech, ✅ Trading, ✅ Cryptocurrency, ✅ Banking, ✅ Data processing, ✅ Healthcare, ✅ Social Networking and more. Do you feel this is what you need? Let's schedule a quick call and find out how we could help you to grow Some keywords: Java, Spring, Spring Boot, Spring Framework, Backend, Back-end, Back-end developer, Backend developer, Hibernate, Kafka, Testcontainers, MongoDB, MySQL, PostgreSQL, Docker, AWS, RESTful API, DB design, Database design, database
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    MySQL
    MongoDB
    Spring Boot
    Kubernetes
    RabbitMQ
    RESTful API
    Elasticsearch
    Amazon EC2
    Docker
    Hibernate
    Spring Framework
    Java
    SQL
    Apache Kafka
  • $40 hourly
    My name is Emil Zajac. I am a software developer currently based in Warsaw. I am a full stack flutter developer with expertise in firebase as a backend and in-depth knowledge of Dart. While earning my Master of Engineering degree, I also developed a wide range of experience in web applications, including NodeJs, React, Html, PHP, SQL, PostgreSQL, C++, Python, Java, and others.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Firebase Realtime Database
    Agile Software Development
    Software Development
    Dart
    GitHub
    Firebase
    RESTful API
    TypeScript
    Problem Solving
    Mobile UI Design
    Computer Science
    JavaScript
    Node.js
  • $45 hourly
    I am an experienced individual contractor with 6 years of experience in working on various projects. I have the ability to work with legacy systems of high complexity as well as new projects, which allows me to adapt to different project requirements. I am an excellent organizer of my time, able to independently plan my work and manage projects. It is not a problem for me to find a balance between product and technical requirements, which allows me to deliver solutions that meet client expectations. I am always interested in talking with clients and identifying their business requirements, which allows me to deliver solutions tailored exactly to their needs. Working with clients is a pleasure for me and allows me to better understand their needs. My career is full of challenges, but thanks to my skills and approach to work, I am able to deliver high-quality solutions for clients that meet their requirements.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Architecture
    Magento
    Code Review
    Code Refactoring
    MySQL
    Laravel
    Symfony
    Amazon Web Services
    RESTful API
    PHP
    PostgreSQL
    Microservice
  • $38 hourly
    I'm a highly focused and motivated software developer. Organized, methodical and a keen eye for detail results in solid coding and trustworthy mobile apps. Transforming client requirements into great apps based on a clear and quality code are core values in achieving long-lasting relationships. Technologies & tools Kotlin 5 years Android 5 years Swift 4 years iOS 3 years Dart 3 years Flutter 3 years
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    RESTful API
    API
    Blockchain
    Android SDK
    Flutter
    Kotlin
    C++
    Swift
    Firebase
    API Integration
    Android
    Android App Development
    iOS
  • $125 hourly
    Software engineer with 10+ years of experience in development and devOps. Recent projects: * Fintech project (golang) * Custom connectors for Zapier, Workato, Terraform, Crossplane, Pulumi * Datasets management platform for Computer Vision projects (python) * IoT platform (golang) Skills: golang, python, devops, custom integrations
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Golang
    Docker
    RESTful API
    DevOps
    Terraform
    Application Release Automation
    Git
    API
    Python
    Scripting
    Zapier
    API Integration
    Automation
  • $60 hourly
    More than 10 years of production experience. I have good knowledge in different types of architectures: # Hexagonal/Onion/Clean Domain Centric Architectures # Classic 3 Layers DataBase Centric Architecture # Domain Driven Design # CQRS patterns, Event Sourcing, Event Streaming and Historical Modelling
# Distributed Event-Driven systems, complex systems with SAGAs # Microservices, Docker, Containerised Apps & Kubernetes # Security with OAuth2 & OpenIdConnect, JWT, mTLS
 I’m fond of designing encapsulated domain models (Domain Driven Design) and building Microservices using modern architectures with CQRS patterns. Skills: # C#, .NET, Web Api # Entity Framework, Dapper # T-SQL, MS SQL Server, MySQL # TDD, SpecFlow, unit & integration tests # SVN, Git, Scrum Biggest Projects ever worked on: # Senior Software Engineer at PaySafe - a market leader with over 25 years of experience in payments. My the most responsible task: I personally participated as a key developer in creating the backend architecture for a child PaySafe product: SafetyPay. It’s a high load system which processes millions of payment transactions a month.

 # Elateral Marketing Service Cloud. I personally worked on the features for the following customers: Coca-Cola, Procter & Gamble, Motorola, Toyota. I used a NServiceBus SAGA to develop complex fulfilment process. There were more than 150 developers, QAs, BAs, Managers on the project. Methodologies I currently apply to my software development process: # Abstractions: this is important thing because it's the only way to build complex systems in easy way. Usually I use 5-8 abstractions maximum in a single piece of code/level because it's very difficult for a human brain to keep in mind more than 5-8 things at the same time. # Domain Driven Design # Profiling SQL queries # GoF patterns # SOLID principles # Estimating the complexity of algorithms O(1) O(N)... # Well designed REST apis # DRY # Microservices # Encapsulation
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    .NET Core
    Domain-Driven Design
    Test-Driven Development
    Clean Architecture
    RESTful API
    Transact-SQL
    C#
    MySQL
    Entity Framework
    Microservice
  • $50 hourly
    More than 10 years of successful development of a wide range of commercial web applications using .NET Core, ASP.NET, Web API, SOAP and REST Web Services, Xamarin and Cordova based mobile apps. Great architecture abilities for highly scalable solutions Microsoft Certified Software Developer: MCSD: Web Applications Experienced with Microsoft Azure cloud ecosystem, including Azure App Services, Azure Storage (Blob, Queue, Table), Kubernetes clusters and Service Fabric clusters. Have strong skills in Microsoft SQL Server and PostgreSQL. Had experience in Microsoft Bot Framework. Backend stack: .NET 6, .NET Core, Web API, .NET Core Identity, ASP.NET MVC, Entity Framework, Azure cloud platform, Google Cloud, AWS, Node.js Data storage: Microsoft SQL Server, PostgreSQL, MongoDB, Azure Cosmos DB, AWS Aurora, AWS Dynamo DB ORM: Entity Framework, Dapper, NHibernate No-SQL: MongoDB, Firebase DB, Redis, Elastic, Cosmos DB Frontend technologies stack: Vue.js, React, Angular, Javascript, Typescript, HTML5, CSS, Bootstrap, jQuery, LESS, SASS Test frameworks/tools: NUnit, xUnit, Selenium, Selenium Web Driver, Postman, jMeter Payment Systems integrations: PayPal, Stripe API, Flutterwave 3rd pary integrations: HelloSign, Google APIs, SigningHub, RestPack, Mailchimp, TINCheck, Experian, MasterCard MATCH, GIACT, Equifax, TransUnion Cloud solutions: Microsoft Azure, Google Cloud Services, Amazon Web Services Logging: Kibana, Elastic, Google StackDriver CI/CD: Azure DevOps,TeamCity, Octopus, Jenkins, Terraform Top projects: CRM System for Payment Gateway (NDA) Project goal: Migration from Salesforce to a self-developed CRM system with highly automated workflows Overview: CRM systems for US Payment Gateway business flows ie lead management, underwriting and processing of the third-party data ie Credit Score checks, Payment Gateways history checks, Fraud alerts Technologies: - .NET Core, .NET Core Web API - Entity Framework Core - PostgreSQL - Redis - React - Google Stack Driver - Kubernetes - Google Cloud Position / Responsibilities: Technical Lead of a team of 3 full-stack, 2 frontends and QAs Technical architecture design and implementation, requirements investigation, business process planning, task management License Plates Recognition (NDA) Project goal: Software for automatic license plate recognition. Creation of the infrastructure and apps for parking solutions in Europe. Overview: CRM systems for Parking Providers in Europe including booking, administration, and parking violations checks Technologies: - .NET Core, .NET Core Web API - Entity Framework Core - PostgreSQL - Elastic - Kibana - Kubernetes - AWS Position / Responsibilities: Technical architecture design and implementation, diagrams, documentation, requirements the investigation, business process planning, task management, optimization, scalability, code reviews 2018 – 2020 London-based Cloud Solution for Video/Image storage with image recognition and similarity detection (NDA) Project goal: Cloud software is primarily for creative people like designers, artists, and photographers to share their portfolios and do the edits and delivery online. Ability to find the best candidate for a job by uploading of a reference image. Ability to hire, track and pay for a job. Overview: Web solution for storing and editing the images and videos with the ability to share and portfolio management to find a job. Technologies: - .NET Core, .NET Core Web API - Entity Framework Core - MS SQL Server - Elastic - Vue.js - Azure Position / Responsibilities: Technical Lead / Architect Technical architecture design and implementation, diagrams, documentation Scalability enhancements Semantic core development for the image recognition and similarity detection software 2020 – 2021 Unity Mobile Game – Server Side Architecture and Development (NDA) Overview: Backend Development + CMS for a mobile game Technologies: - .NET Core, .NET Core Web API - Entity Framework Core - Amazon Aurora (PostgreSQL) - Elastic - Vue.js - Terraform - AWS Lambda - Web Sockets Position / Responsibilities: Technical Lead / Architect Backend performance tuning, Web Sockets implementation, AWS Lambda scalability and performance optimization, AWS cost optimization, CMS development (vue.js), API development, Business process overview, delivery planning 2021 – 2022 Warranties and loads for US automotive market Overview: US-based solution for auto warranties and loans with lead management and underwriting features Technologies: - CQRS pattern (MediatR) - .NET Core, Web API - Azure - Elastic - React - Azure DevOps - CosmosDB (Mongo syntax) - Web Sockets - Service Bus - Service Fabric, Azure App Services - Azure Functions (serverless) Position / Responsibilities: Technical Lead / Architect Third-party connection infrastructure development. Migration from Service Fabric to App Services. Performance optimization. Architecture review. High load stable infrastructure development.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    API
    .NET Core
    .NET Stack
    Microsoft Azure
    Google Cloud Platform
    RESTful API
    Azure Cosmos DB
    C#
    ASP.NET
    ASP.NET MVC
    SQL
    MongoDB
    ASP.NET Core
    PostgreSQL
    Web Development
  • $50 hourly
    I am having more than ten years of experience in Web and Software Development. I have developed many backend projects and frontend projects for middle to big companies. There are IoT and Commercial, Social, Mobile backend projects. Usually, I used PHP/Drupal/Laravel and Postgresql/Mysql for backend development. For the frontend, I used Vue.js, AngularJS. TECHNICAL SKILLS: ● Drupal: themes, modules, core ( Over 10 years ); ● XML/HTML/CSS ( Over 12 years ); ● PHP ( Over 11 years ); ● Symfony/CakePHP/Laravel ( Over 7 years ); ● Javascript, Vue, React, Angular ( Over 6 years ); ● MySQL, PostgreSQL, MongoDB, SQL ( Over 6 years ); ● Swagger, OpenAPI Spec ● Web-services (SOAP, REST); ● GIT ( Over 5 years ); ● Responsive design ( Over 5 years ) Thank you
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Web Development
    Symfony
    RESTful API
    Security Engineering
    DevOps
    RESTful Architecture
    Docker
    Laravel
    Drupal
    SQL
    HTML
    CSS
    PostgreSQL
    PHP
    Python
  • $25 hourly
    Software Engineer, who likes quality. Experience in designing and developing software and databases from scratch, implementation of new software solutions. Solid knowledge in .NET, web application, desktop application development, Client/Server side web applications development, database development. Experience in optimizing query performance on the MS SQL Server, transfer existing software solutions to modern technologies. Professional interests include development methodologies, software design, internet of things. Solid background development process including design, estimating, coding, testing, debugging. Strengths include: • New application development, refactoring and improvement of existing applications. • Web and desktop applications development. • Using OOP, Design Patterns. • Experience in Unit Testing. • Technical Problem Solving, Team Working • Good communication and team coordination skills
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    NHibernate
    RESTful API
    Ecommerce Website
    DevExpress
    ASP.NET MVC
    Microservice
    ASP.NET Web API
    ASP.NET Core
    SQL
    C#
    PostgreSQL
  • $45 hourly
    I am the top Sofrware Engineer with over 9 years expiriece in Application development. I focus mainly on: Python / Java / Node JS / Android development * AI * Backend development (servers, APIs, DBs); * Application develoment (desktop / mobile apps, bots, etc.); * Network development (protocols implementations); * Telecomunications (VoIP/IMS develoment and configuration).
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Data Scraping
    Docker
    DevOps
    RESTful API
    Node.js
    Android App Development
    Django
    Java
    PHP
    Python
    Kotlin
    HTML5
    WordPress
    CSS
  • $45 hourly
    I am a professional full-stack PHP/Symfony/Laravel developer. I have 12 years of commercial experience in PHP development that covers websites and dedicated systems built in Symfony/Laravel, VueJS or custom PHP. I'm very comfortable working with frontend - VueJS, HTML, CSS/SASS. I am a part of the Polcode team, a Polish software development company established in 2006 with over 150 developers, designers, project managers, DevOps and QA specialists onboard. This means that besides my programming skills you always have access to a full-stack product design & development team. My main competencies are: - Symfony/Laravel/PHP based applications - Vue.js (static sites with Nuxt.js, PWA, SPA) applications or reusable components - Creating or consuming REST services - Creating applications using PostgreSQL, MySQL, Elastic Search - VPS configuration and basic management - Working in Linux or Windows with WSL environment - Docker My technology stack: Backend PHP | Symfony - Doctrine - Twig | Laravel | MySQL | PostgreSQL | Elastic Search Frontend VueJS | Nuxt.js | Vuetify | jQuery | HTML | CSS - SCSS/LESS | Bulma | Twitter Bootstrap | Webpack More about Polcode Polcode provides customized software solutions for startups, SaaS companies, eCommerce stores, and enterprise clients worldwide. From building the product from scratch to extending the existing teams, we have expertise in a diverse set of open source technologies and platforms to bring innovation in an agile fashion. Our team excels in PHP, Symfony, Laravel, Magento, Go, React Native, React.js, Vue.js, Ruby on Rails and Angular. With over 150 people, Polcode has either empowered client teams or delivered end-to-end development projects for brands from fintech, manufacturing, consulting, eCommerce, marketing or eLearning industries and is recognized as Top Developer in Poland by Clutch. Looking forward to our cooperation! Karol, Polcode Dev Team
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    PHP
    React
    Symfony
    AJAX
    Laravel
    Vuetify
    Docker
    JavaScript
    Vue.js
    Bulma
    RESTful API
    Bootstrap
  • $33 hourly
    I am Android developer with more than 5 years commercial experience and focusing on native Android development. I am using Kotlin and JAVA languages. I am responsible and flexible during implementation processes, understand principles around app UX, pretty good at architecture and design patterns. Friendly, honest and hard-working. I’ve graduated Yanka Kupala State University of Grodno as a Math-System programmer.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Agile CRM
    RESTful API
    SSL
    SOAP
    ScrumWorks
    Bluetooth LE
    XML
    RxJava
    Dagger 2
    Koin
    C#
    Kotlin
    C++
    Java
  • $50 hourly
    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.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Cloud Computing
    Chatbot Development
    VoIP
    FreeSWITCH
    Product Development
    RabbitMQ
    Automatic Speech Recognition
    API
    Python
    API Development
    PostgreSQL
    Cloud Services
    C++
    RESTful API
    Architecture
    Architectural Design
  • $40 hourly
    Iam a java developer with a +4 experience of building restful/soap api and various backend applications. I expertise in creating microservices application in plain spring cloud or in integration with aks (Azure kubernetes).
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Selenium
    Postman
    Jakarta Messaging
    SOAP
    Cloud Architecture
    Microsoft Azure
    Apache Kafka
    Kubernetes
    Spring Data
    Mockito
    Spring Batch
    Docker
    Microservice
    Spring Boot
    RESTful API
  • $55 hourly
    Overall more than 12 years of web development experience. 10+ years SFCC (former Demandware) experience as Backend/Fullstack Developer. Strong problem solver, API and services integrations with minimum documentation. SFRA deep structure and capabilities knowledge. Business manager customization, OCAPI experience. Technologies stack: Javascript, SOAP/REST, PHP, MySQL, HTML, CSS, and more. Proven ability to develop and optimize web systems for performance and scalability. Currently I have participated in more than 70 projects from medium to enterprise size.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    SOAP
    Back-End Development
    ECMAScript
    RESTful API
    Demandware
    Node.js
    HTML
    PHP
    JavaScript
    Magento
  • $13 hourly
    I am a skilled Java developer with extensive experience in building high-performance, scalable, and reliable applications. With over 3 years of experience in the industry, I have honed my skills in Java development, including core Java, J2EE, Spring Framework, Hibernate, and Maven.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Automation
    Scripting
    Data Scraping
    AWS Application
    Oracle
    AWS Amplify
    Docker
    Kotlin
    RESTful Architecture
    Java
    Golang
    RESTful API
    MySQL
    Spring Framework
    Redis
  • $30 hourly
    I would describe myself as highly curious and focused on learning in all parts of life, personal and professional. In my professional life, I look for the hardest problems to solve and where I can learn and develop the most. I’ve taken on many different types of projects, including ads, virtual reality, commerce, and messaging. No matter what I’m working on, I’m so invested. My skills: 🔹JavaScript 🔸TypeScript 🔹Vue.js v2, v3/Nuxt.js 🔸Angular 2 ~ 15 🔹React.js/Next.js 🔹Node.js 🔸Express.js 🔹Laravel 🔸Ruby on Rails 🔹Golang 🔸Python 🔸Django 🔹PostgreSQL 🔸MongoDB 🔹Docker 🔸Kubernetes 🔹RESTful API 🔸GraphQL With my comprehensive skill set and experience, I am confident in delivering high-quality solutions that meet the needs of clients and drive business success. I am passionate about leveraging my technical expertise to develop innovative and efficient systems while ensuring optimal user experiences.
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    Web Scraping
    React
    ExpressJS
    Node.js
    JavaScript
    GraphQL
    RESTful API
    Kubernetes
    Docker
    MongoDB
    PostgreSQL
    Django
    TypeScript
    Golang
    Python
  • $35 hourly
    I'm with 9+ years of experience building complex software solutions. 🙋‍♂️ My main business domains are:✔️𝗠𝗮𝗿𝗧𝗲𝗰𝗵, ✔️𝗘𝗱𝗧𝗲𝗰𝗵, ✔️𝗙𝗶𝗻𝗧𝗲𝗰𝗵, ✔️𝗠𝗲𝗱𝗧𝗲𝗰𝗵, ✔️𝗪𝗲𝗯3️⃣, ✔️𝗕𝗹𝗼𝗰𝗸𝗰𝗵𝗮𝗶𝗻, ✔️𝗔𝗜. However, I've had tremendous experience with all types of SaaS and software solution development. 📅 Booking is available the same day during EST/CST business hours, but message me ASAP. My mission is to help you Grow-Your-Business Exponentially by providing reliable and efficient IT solutions within a realistic budget and time frame. It's important to me to build long-term relationships with my clients, so I primarily look for long-term projects. Highly skilled in designing, developing, and deploying pixel-perfect and cross-platform web applications using, ⚡️𝐅𝐫𝐨𝐧𝐭-𝐞𝐧𝐝 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 𝐒𝐭𝐚𝐜𝐤𝐬: ◉ CMS: WordPress, Shopify, WebFlow, Bubble.io, SquareSpace, and WIX ◉ HTML5/CCS3: Responsive and cross-browser PSD to HTML or Sketch to HTML ◉ Vue.js, Nuxt.js, Vuex, Vuetify, React.js, and Angular.js, Next.js, Redux. ◉ Bootstrap, Tailwind CSS, Material UI, HTML, and CSS. ------------------ ⚡️𝐁𝐚𝐜𝐤-𝐞𝐧𝐝 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 𝐒𝐭𝐚𝐜𝐤𝐬: ◉ PHP 5.4 – 8.2, Laravel, Cake PHP ◉ Python, Django ◉ Node.js, Angular.js, Express, Sass, Less, Gulp, Webpack, NPM, AJAX, Axios, and jQuery ◉ RESTful API, JSON, 3rd Party API ◉ AWS, Docker, Jira, Git, CI/CD ◉ PostgreSQL, MySQL, MongoDB, SQLite, and Redis ------------------ ⚡️𝗕𝗹𝗼𝗰𝗸𝗰𝗵𝗮𝗶𝗻 𝗮𝗻𝗱 𝗰𝗿𝘆𝗽𝘁𝗼𝗰𝘂𝗿𝗿𝗲𝗻𝗰𝘆: ◉ Core blockchain development, Smart contracts, ◉ Decentralized applications (DApps) for DeFi ecosystems and Wallets (crypto/fiat), NFT platforms and marketplaces, Trading systems, and exchanges (both centralized and decentralized), banking and payment systems, Governance platforms, etc. ⚡️𝐂𝐡𝐚𝐭𝐛𝐨𝐭 𝐝𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭: I can build and integrate ChatGPT with different apps and create custom Chatbots for various platforms. ◉ Generative AI: GPT-3, GPT-4, ChatGPT, OpenAI; ◉ Prompt Engineering, Botpress, Flowise, Langchain; ◉ API development, Chatbot integrations. ⚡️𝐀𝐏𝐈 𝐝𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭: ◉ Backend development is very close to proper architecture, so in my experience, it's best to start with requirements and architecture development, after which I can help you with API development for anything from a very simple backend to a highly loaded distributed cloud infrastructure. ------------------ ✅ Have any questions? Feel free to contact me! I'll cut straight to the point on your project, but for now, here is a magical unicorn for you 🦄 Best part? I'm flexible with my working hours and will be happy to discuss your project at your earliest convenience 💕. So what are you waiting for??? Let's get started!!! ......... I'm looking forward to making your next project a success. Reach out today!🙋‍♂️ Thanks
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    CSS
    HTML
    Front-End Development
    Next.js
    Web3
    API Development
    RESTful API
    Web Application
    D3.js
    AWS Development
    GraphQL
    React
    TypeScript
    Node.js
    JavaScript
  • $35 hourly
    With more than 8 years of experience as a Sr. Full Stack Engineer, I've had the opportunity to work on a diverse range of digital platforms and innovative projects. My commitment to staying up-to-date with the latest technologies and trends, as well as my passionate interest in creating seamless user experiences and effective backend systems, empowers me to be a well-rounded and versatile developer. Skills ✅HTML5, CSS3, JavaScript (ES6), TypeScript ✅Front-end frameworks: React, Vue.js, Angular ✅Backend technologies: Node.js, Express.js, Python, Django, Flask ✅Databases: PostgreSQL, MongoDB, MySQL, Firebase ✅Version Control/Git ✅DevOps: Docker, Kubernetes, Jenkins, AWS, Azure, GCP ✅RESTful API development, GraphQL ✅Test-driven development (Jest, Mocha, Jasmine) ✅Agile/Scrum methodologies ✅Excellent problem-solving skills ✅Strong communication and team collaboration skills ✅Attention to detail My expertise lies in a wide range of tech stacks containing - Node.js, React.js, Angular.js (Front-end); Java, PHP, Python and .NET (Back-end) including solid experience with databases like MySQL, PostgreSQL, MongoDB, and Oracle. My skills extend to building cloud solutions with AWS, Google Cloud, and Microsoft Azure. As a technologist, my passion for coding goes beyond work hours. Open-source contribution is an integral part of my professional journey, exposing me to projects and challenges outside my day-to-day role. I have delivered tech talks at different developer meetups and conferences to share my knowledge and insights. My approach to work emulates an Agile framework, which ensures effective interaction between team members, timely delivery at each Sprint End, and meeting the product owners' expectations. With proficiency in delivering high-performance applications, I also prioritize writing clean, efficient, and maintainable code. I believe in building long-term professional relationships and my clients' satisfaction is of paramount importance to me. Whether you're looking for a trusted tech lead or need to troubleshoot an ailing project, feel free to connect with me. I'm open to exciting opportunities and challenging problems worth solving. Warm Regards
    vsuc_fltilesrefresh_TrophyIcon Backend Rest API
    React Native
    Figma
    Front-End Development
    Vue.js
    Redux
    RESTful API
    Tailwind CSS
    Node.js
    Next.js
    Amazon Web Services
    TypeScript
    Python
    Web Development
    React
    HTML
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