Hire the Best Object Oriented Programming (OOP) Specialists

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Nhân L.

Ho Chi Minh, Vietnam

$6/hr
5.0
3 jobs

I build production-ready backend systems that scale. Recently shipped platforms serving 50M+ users at VNG Corporation with 99.9% uptime. ✓ 3 years at VNG Corp (Vietnam's #1 tech company) — game servers handling thousands CCU, payment integration across SEA markets ✓ Full-stack: Node.js, Python, TypeScript, Next.js, React ✓ DevOps: Docker, Linux, systemd, CI/CD — air-gapped RHEL 9.6 deployments ✓ UTC+7 timezone — your code ships while you sleep, 3-4hr overlap with AU/EU business hours What I do best: • Backend architecture — Node.js/Python APIs, dual-DB systems, payment gateways (Stripe, Google/Apple IAP) • DevOps — Docker multi-shard migrations, systemd service management, SSH-based monitoring tools • AI integration — OpenAI gateway streaming, AI-powered CRM, OCR automation pipelines I work independently, communicate proactively in clear English, and treat your project like my own. No hand-holding needed — I'll flag risks early, suggest improvements, and deliver on time. Let's discuss your project — send me a message and I'll respond within the hour.

  • Java
  • JavaScript
  • Game Development
  • Android
  • iOS
  • Python
  • Linux
  • Ubuntu
  • Node.js
  • Data Processing
  • Data Collection
  • Vietnamese
  • Data Profiling
  • Data Analysis
  • PDF Conversion
  • Visual Basic for Applications
Vishal G.

Bengaluru, India

$25/hr
5.0
10 jobs

Looking for a Full-Stack .NET Developer, AI Specialist, and Automation Engineer who handles everything from complex backend architecture to sleek React frontends and CAD plugins? Finding a reliable developer is hard; finding a Product Engineer who understands system design, automated workflows, and business ROI is even rarer. I bridge that gap by combining deep technical expertise with a consultative mindset. Whether you need custom AI/ML integrations, SolidWorks CAD automation, or high-throughput .NET enterprise platforms, I engineer solutions built on Clean Architecture, microservices, and Test-Driven Development (TDD) to ensure scalable, maintainable, and cost-effective code. What I Build & Automate: AI & Computer Vision Systems: Custom Machine Learning pipelines, RAG (Retrieval-Augmented Generation) applications, and real-time OpenCV image/video processing. CAD & Desktop Automation: Custom SolidWorks API plugins (C#/.NET), Office Add-ins (VSTO & Office.js for Outlook, Excel, OneNote), and WPF desktop tools. Full-Stack Web & APIs: High-performance RESTful APIs, asynchronous microservices, and modern, responsive React dashboards. Core Technical Stack & Expertise AI, Machine Learning & Data: Python, OpenCV (Computer Vision), RAG / LLM Integration, Machine Learning Models, Apache Airflow, Streamlit CAD & Extension Engineering: SolidWorks API (C#), VSTO, Office.js, Outlook & Excel Add-ins, System Automation Backend & Cloud Architecture: C#, .NET 8 / .NET Core, FastAPI, PostgreSQL, SQL Server, Microservices, RESTful APIs Frontend & Mobile: TypeScript, JavaScript, React, .NET MAUI, WPF, Modern UI/UX DevOps & Infrastructure: Microsoft Azure, Docker, Apache Kafka, CI/CD Pipelines, Git Digital Wallet Integrations: Apple Wallet Pass, Google Wallet API I pride myself on transparent Agile communication and delivering logic that is as clean as it is powerful. Let’s connect to discuss your project requirements and turn your technical vision into a production-ready reality.

  • C#
  • .NET Core
  • Microsoft Office
  • React
  • Python
  • Machine Learning
  • Data Science
  • AI Implementation
  • Robotics
  • Design-to-Code
  • Data Engineering
  • Data Extraction
Maroof K.

Shahjahanpur, India

$25/hr
5.0
10 jobs

I help businesses build and modernize enterprise software that integrates seamlessly with complex business workflows. I have 15+ years of professional experience, I've delivered WINDOWS DESKTOP applications, ENTERPRISE WEB platforms, POS, KIOSK, ERP, backend services, workflow automation, and integration solutions for clients across the USA, UK, and Australia. My focus is solving complex engineering problems where reliability, scalability, and maintainability are critical. I specialize in Software/Tool development using .NET Framework and .NET Core. Alongside enterprise development, I help organizations adopt AI where it delivers measurable value. I build intelligent document processing, Retrieval-Augmented Generation (RAG) systems, AI agents, semantic search, OCR pipelines, and workflow automation using Azure OpenAI and modern LLM technologies. My approach is practical: AI should improve productivity and business processes—not simply add complexity. ### Core Expertise ✔Enterprise Software Development * C#, .NET, ASP.NET Core, Blazor * WPF, WinForms, .NET MAUI * Entity Framework Core * SQL Server * REST APIs & GraphQL * Windows Services * Azure & Cloud Solutions * QR Code, Bar Code ### Industry Experience ✔ AI & Intelligent Automation ✔ Transport & Fleet Management ERP ✔ Healthcare & Medical Billing ✔ Retail POS & Inventory Management ✔ Payroll & Attendance Systems ✔ School & College Management ✔ Manufacturing & Industrial Automation ✔ Financial & Invoicing Solutions **Desktop & Hardware Integration** * Windows API * USB & Serial Communication * Driver Communication * Industrial Equipment Integration * Label Printers, Barcode Scanners, Weighing Scales * Smart Card & ID Card Printers **Healthcare EDI Solutions** * ANSI X12 * EDI 837P / 837I * EDI 835 * EDI 277 * EDI 999 * Healthcare Billing Systems * Clearinghouse Integrations **Biometric & Attendance Systems** * ZKTeco * eSSL * Mantra * Cogent * Suprema * Safran * Fingerprint SDK Integration **Technical Publications & XML** * S1000D * DITA * XML * XSLT * BREX * Data Modules * Schema Validation * Publishing Automation **AI & Intelligent Automation** * Azure OpenAI * Large Language Models (LLMs) * Retrieval-Augmented Generation (RAG) * AI Agents * Semantic Search * OCR * ETL * Document Intelligence * Workflow Automation If you're looking for a senior engineer who can understand complex business requirements, modernize legacy systems, integrate enterprise technologies, and deliver production-ready software, I'd be glad to discuss your project.

  • C#
  • .NET Core
  • Windows Forms
  • Blazor
  • Windows Presentation Foundation
  • .NET Framework
  • ASP.NET Web API
  • ASP.NET MVC
  • VB.NET
  • Git
  • Microsoft SQL Server
  • React
  • Selenium
  • Desktop Application
  • Standalone Application
  • Web Development
  • Mobile App Development
  • Android App Development
  • iOS Development
  • API Integration
Aleksandr K.

Warsaw, Poland

$35/hr
4.8
52 jobs

Hello! My name is Aleksandr Kalinin. I have a double major in Math and CS. I have been programming professionally since 2006. Skills: C++ 11/14/17/20/23, STL, SIMD (SSE, AVX, AVX512), CMake, vcpkg, Conan, Boost, perf, VTune. Python, Data Science, NumPy, Pandas, Matplotlib. Rust, tokio. C#. Algorithms, Data Structures, Computational Geometry, Optimization, Linear Algebra, Numerical Methods. Concurrent Programming, Multithreading, Lock-free Programming. CUDA, HIP, OpenCL, Compute Shaders, Halide, TBB, OneAPI. MATLAB, SageMath, Mathematica. Graphics Programming, Vulkan, Metal, DirectX 12, OpenGL, HLSL, GLSL, MSL, Slang, Real-time Rendering, Custom Engine Development. Unreal Engine 4/5, UE5 (3D, PCG, Geometry Scripting, Control Rig, Niagara, UMG, Slate, GAS, Chaos Cloth), Unity, Godot, Cocos2dx Machine Learning, Deep Learning, PyTorch, TensorFlow, Scikit-Learn, ONNX, TensorRT. Computer Vision, Image Processing, OpenCV, Roboflow, Triton, YOLO, YOLOv11, DETR, RT-DETR, Faster R-CNN, R-CNN, U-Net, DeepLabV3+, SAM, SAM2, SegFormer, ResNet, ConvNeXt, ViT, Swin. Optimization / Solvers: OR-Tools (CP-SAT), Z3, MiniSAT, SCIP, HiGHS, IPOPT, MiniZinc. Point Cloud Processing, Collision Detection, Physics Simulation. Maya API, Houdini API (HDK, VEX, HScript), Blender Python API, Pipeline Tools Development. Software Porting, Game Development. Qt, QML, PySide6, JUCE, WxWidgets, VTK. iOS Development, Swift, Objective-C, UIKit, AVFoundation, Metal. Android Development, NDK. FFmpeg WebRTC, RTMP, RTSP, SRT, HLS, NDI, MPEG-DASH, CMAF, WebTransport, QUIC, UDP/RTP/RTCP, TCP, WebSockets, HTTP Live Streaming pipelines, Video Processing, Real-time Streaming Systems. JavaScript, Node.js, Three.js, Pixi.js. Docker, Kubernetes, AWS, EKS, CI/CD, n8n. PostgreSQL, Supabase. Windows, Mac, Linux. AI, Claude Code.

  • OpenCV
  • C++
  • Python
  • Machine Learning
  • Mathematica
  • Mathematics
  • MATLAB
  • Image Processing
  • DirectX
  • OpenGL
  • Microsoft Windows
  • Geometry
  • 3D Graphics Framework
  • CMake
  • Computer Graphics
Vitalii A.

Wroclaw, Poland

$30/hr
5.0
37 jobs

I have more than 15 years of programming experience. As a freelancer, I have broad experience: I developed web (ASP.NET, Python, PHP), desktop (C++, C#, Python — Linux and Windows) and mobile (Android — Java, C++) applications. I list here some of my jobs. C#: * clubspeed.com — a large software suite for family entertainment clubs; included C# code (80%), including CoreApi and ASP.NET Razor, plus PHP (Laravel) and Node.js code (for low-level car racing control tasks). I developed it as a team member. * qadra.com — a financial company; C# code (80%), Python (some microservices are Python/Flask based, 20% of code), AWS-hosted with Docker containers and Lambdas. I developed it as a team member. * enven.nl — implemented from scratch their non-public partners portal: ASP.NET Razor and some CoreApi endpoints. * ASP.NET website for house rentals. * ASP.NET website for remote control of a robotic device via a WebSocket connection. * Vegetable-oil plant automation desktop program (C# + WinCC). Python: * Embeddable fact-checking chat that uses the LangGraph framework to implement a customizable LLM/AI backend (OpenAI, DeepSeek, Hugging Face, or Ollama). It allows administrators to embed the component in their websites so users can ask questions about facts described in articles and verify whether facts listed in an article are true. It included agentic code and many external APIs to check facts (not just asking an LLM), and even computer vision to inspect website photos (OpenCV). Backend is FastAPI. * AI/LLM-based ad selection for a website (FastAPI and LangGraph). It processes website text or chat messages and selects ads of different types related to the content. It contains SDKs for embedding ads on many platforms, including Go, React, and plain HTML. * Polish-language training software, based on Django and LangGraph. * Many small projects: desktop scripts, web scraping (Selenium and related tools), and simple AI agents. C++: * Factory equipment monitoring system (Ubuntu Linux, custom server over TCP/IP, web interface in PHP). * Many small projects, some of which are mentioned in reviews on this profile; many are non-public. * Powerful software for automated ad submission on social networks (massive bots that send millions of messages). PHP: * 20+ websites — without CMS, with my own CMS, and with open-source Drupal, WordPress and Joomla CMSs. * Backends for Android applications. Android: * SOCKS5 proxy application that allows sharing mobile VPN with non-mobile clients via the SOCKS protocol. * Many WebView-based "business card" applications. * Dating-related applications, including erotic puzzles. Human emulation: * Spam bots — I cannot provide a specific list of such software for legal reasons. * Automatic checkout on eBay and similar websites. * PayPal automatic payments. * Data scraping, including air tickets and goods in online stores. Reverse engineering — I cannot provide a specific list of reverse-engineered software for legal reasons. * Java bytecode reverse engineering, including Android. * .NET bytecode reverse engineering. * Machine code for 32-bit and 64-bit x86 and ARM CPUs. Assembler: * High-performance cryptographic library for x86\_64 CPUs.

  • .NET Framework
  • MySQL Programming
  • JavaScript
  • PHP
  • Python
  • ASP.NET
  • VB.NET
  • Node.js
  • HTML
  • C#
  • Java
  • C++
  • .NET Core
  • ASP.NET Core
  • .NET Stack
  • Microsoft Windows
  • Android
  • Linux
Otabek X.

Kosonsoy, Uzbekistan

$30/hr
5.0
26 jobs

𝐋𝐞𝐭'𝐬 𝐜𝐫𝐚𝐜𝐤: 𝐆𝐨𝐨𝐠𝐥𝐞, 𝐌𝐞𝐭𝐚, 𝐀𝐦𝐚𝐳𝐨𝐧, 𝐌𝐢𝐜𝐫𝐨𝐬𝐨𝐟𝐭, 𝐞𝐭𝐜 - 𝐂𝐨𝐝𝐢𝐧𝐠 𝐈𝐧𝐭𝐞𝐫𝐯𝐢𝐞𝐰𝐬 🚀🚀🚀 🧠 𝗪𝗵𝗮𝘁 𝗜 𝗢𝗳𝗳𝗲𝗿: — 1-on-1 mentoring for FAANG interviews — Deep dive into LeetCode patterns — Custom roadmap for your level ⭐️ 𝗥𝗲𝗮𝗱 𝗪𝗵𝗮𝘁 𝗠𝘆 𝗦𝘁𝘂𝗱𝗲𝗻𝘁𝘀 𝗧𝗲𝗹𝗹 𝗔𝗯𝗼𝘂𝘁 𝗠𝗲: "𝘐 𝘩𝘪𝘨𝘩𝘭𝘺 𝘳𝘦𝘤𝘰𝘮𝘮𝘦𝘯𝘥 𝘮𝘺 𝘮𝘦𝘯𝘵𝘰𝘳 𝘧𝘰𝘳 𝘩𝘪𝘴 𝘦𝘹𝘤𝘦𝘱𝘵𝘪𝘰𝘯𝘢𝘭 𝘢𝘣𝘪𝘭𝘪𝘵𝘺 𝘵𝘰 𝘵𝘦𝘢𝘤𝘩 𝘓𝘦𝘦𝘵𝘊𝘰𝘥𝘦 𝘢𝘭𝘨𝘰𝘳𝘪𝘵𝘩𝘮𝘴. 𝘏𝘪𝘴 𝘦𝘹𝘱𝘦𝘳𝘵𝘪𝘴𝘦 𝘢𝘯𝘥 𝘱𝘢𝘵𝘪𝘦𝘯𝘵 𝘨𝘶𝘪𝘥𝘢𝘯𝘤𝘦 𝘮𝘢𝘥𝘦 𝘤𝘰𝘮𝘱𝘭𝘦𝘹 𝘤𝘰𝘯𝘤𝘦𝘱𝘵𝘴 𝘦𝘢𝘴𝘺 𝘵𝘰 𝘨𝘳𝘢𝘴𝘱." — 𝘕𝘢𝘩𝘪𝘥 𝘔𝘶𝘴𝘵𝘢𝘧𝘢 (𝘚𝘦𝘯𝘪𝘰𝘳 𝘚𝘰𝘧𝘵𝘸𝘢𝘳𝘦 𝘌𝘯𝘨𝘪𝘯𝘦𝘦𝘳 @ 𝘈𝘴𝘤𝘦𝘯𝘥 𝘛𝘦𝘤𝘩𝘯𝘰𝘭𝘰𝘨𝘺 - 𝘊𝘢𝘭𝘪𝘧𝘰𝘳𝘯𝘪𝘢, 𝘜𝘚𝘈) 🚀 𝗠𝘆 𝗔𝗰𝗵𝗶𝗲𝘃𝗲𝗺𝗲𝗻𝘁𝘀: — Top 1% in LeetCode — 2150+ contest ranking — 1000+ problems solved — 650K views for solutions 𝗜 𝗠𝗲𝗻𝘁𝗼𝗿: LeetCode, Algorithms, Data Structures, Hackerrank, Python, Java, C++, JavaScript, C#, Go, etc. 𝗥𝗲𝗮𝗱𝘆 𝘁𝗼 𝗮𝗰𝗲 𝘆𝗼𝘂𝗿 𝘁𝗲𝗰𝗵 𝗶𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄? 𝗟𝗲𝘁’𝘀 𝗰𝗼𝗻𝗻𝗲𝗰𝘁! 💬

  • Algorithms
  • Data Structures
  • Interview Preparation
  • Mock Interview
  • C#
  • Python
  • Java
  • Coding Lesson
  • Tutoring
  • C++
  • Golang
  • JavaScript
  • HackerRank
  • Artificial Intelligence
  • C

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What Is Object-Oriented Programming and Why Is It Important?

You’ve probably seen most back-end programming languages described as object-oriented programming (OOP)—so what is object-orientation in web development, and why is it important?

At its core, it’s a logic—one we use in daily life. We naturally think of things as objects with attributes and behaviors, and that determines how we interact with them. It’s interacting in the abstract, and it’s why OOP can boost speed and efficiency.

What is abstract interaction?

If you want to change the television channel from your seat, you use a remote control. That remote control is an object with a number of attributes and behaviors hidden inside of it. Without an understanding of those hidden attributes—the microchips, wiring, etc.—you still know and expect that pressing a button will perform that particular function. You’ve interacted with the remote control in the abstract, skipping the steps the remote was designed to carry out. That’s the beauty of OOP—the focus is on how the objects behave, not the code required to tell them how to behave.

So, what are objects?

A car is an example of a complex object, with many attributes. We don’t need to understand all of its internal mechanics, what kind of engine it has, how the gas makes it run, or even where the gas came from in order to know how to interact with it. The car’s behaviors have been made simple for us through object-oriented logic: put the key in the ignition, and the car turns on and gets us where we need to go. The attributes that make this possible—all of the car’s parts, electronics, and engineering—are a “package” we don’t need to break down in order to understand.

Apply this to software building, and it allows developers to break down big, complicated projects into compartmentalized objects, program them to have attributes and behaviors, then essentially set them aside and focus on programming how the objects interact—a higher level of thinking that makes writing code less linear and more efficient. Modern, high-level languages like Python and Ruby are perfect examples of OOP. The fact that they’re able to be so streamlined gets right to the heart of OOP logic.

Object-oriented programming & back-end development

What is object-oriented programming in terms of how a site is built? OOP defines most modern server-side scripting languages, which are the languages back-end developers use to write software and database technology. This behind-the-scenes, server-side technology tells a website or web application how to behave, and also builds the architecture for a site to interact with its database. That scaffolding is how data is delivered and processed, effectively making it the brain of a website. And that’s where object-oriented logic comes into play.

If a website’s brain uses object-oriented logic, it’s designed to think of data as objects. It affects how a site is built from the ground up, how data is organized, how later growth and maintenance of the site will occur, and more.

Benefits of object-oriented technology include:

  • Ease of software design
  • Productivity
  • Easy testing, debugging, and maintenance
  • It’s reusable
  • More thorough data analysis, less development time, and more accurate coding, thanks to OOP’s inheritance method
  • Data is safe and secure, with less data corruption, thanks to hiding and abstraction
  • It’s sharable (classes are reusable and can be distributed to other networks)

The building blocks of object-oriented programming

Objects are central to OOP, but they’re not the only moving part. Here’s a closer look at the other building blocks, and how they work in tandem to create back-end code that houses, moves, and manipulates data from a database into a usable web application.

  1. Objects: An object is the core unit of OOP. Objects are uniquely named and represent an instance of a class. Each object houses different states (attributes), and shared behaviors, called methods. For example, a Prius is an object in the class of “cars,” in a subclass of “hybrid cars.” Its attributes include anything from the number of doors it has to how its electric component is charged. It’s similar to other cars by its behavior—it drives—but its attributes are what set it apart.
  2. Classes: A class is a blueprint for how an object is built, as well as being a sort of “parent category” for objects. Using the previous example, a class dictates the concept of a car—four wheels, an engine, a body, brakes, etc. It allows certain set criteria to be passed down to all objects in the class. All varieties of cars behave relatively the same on a basic level, but its their attributes and methods that make them unique.
  3. Inheritance: This is an important aspect of OOP, hinted at above. By deriving classes from parent classes, behaviors can be passed down to objects, then more complicated attributes can be added the deeper you go. For example, breaking a car into subclasses (car → sports car → V8 sports car) makes it possible to layer in more features without starting from scratch.
  4. Abstraction & Encapsulation: This describes how attributes are housed and hidden within an object—including its data. Objects are designed to only reveal the necessary data, allowing software to interact with the object on a higher level. It’s equal parts security and simplicity. In the case of car parts, by safely stowing them within the body of an assembled car, things are less likely to get broken, and users can interact with the big picture: pressing the gas means go, no questions asked.

Procedural languages vs. object-oriented languages

Procedural programming (via languages like ColdFusion) is code that is broken into “procedures”—it’s a different way of thinking about how code interacts with data that’s more linear. Procedures are functional bits of code that interact with and change data, like little machines that gather input, process it, then deliver output. With OOP, however, data and functions (attributes and methods) are bundled together within the object. This prevents the need for any shared or global data with OOP, which is a core difference between the two approaches.

Traditional procedural languages like C and Pascal require you to think in terms of the computer rather than thinking in terms of the problem you’re trying to solve. For less complicated applications, procedural languages offer ease and transparency that bundled objects don’t always allow—something that can make it more difficult for programmers to analyze smaller bits of code on the tail-end of the development process.

When it comes to creating reusable components in software, OOP is the clear winner. Reusability leads to efficiency, simplifying programming and creating “shortcuts” to software design.

Popular object-oriented languages

  • Simula, the first object-oriented programming language
  • Java
  • Python
  • Ruby
  • C++
  • Smalltalk
  • Visual Basic .NET
  • Objective-C: OOP is a core tenet of iOS mobile app programming, and Objective-C is essentially the C language with an object-oriented layer.
  • Curl
  • Delphi
  • Eiffel