Hire the best Java developers

Check out Java developers with the skills you need for your next job.
Clients rate Java developers
Rating is 4.8 out of 5.
4.8/5
based on 27,630 client reviews
  • $50 hourly
    My name is Saul Hidalgo, a Computer Engineer with a passion for developing Java and .Net software. I have been fortunate to work with exceptional teams and have had the opportunity to contribute to various sectors, including National Security/Defense in the United Kingdom, Oil companies, and Universities such as Harvard Business Publishing. The software I have created is currently being successfully utilized by these organizations. I thrive on new challenges and continuously seek opportunities to expand my skills. You can explore my public contributions on my GitHub account: saulhidalgoaular. Below are my areas of expertise and skills: 1. Code Translation and Conversion: - Proficient in translating code across various languages, with expertise in Python, Java, Delphi, C++, and C#. 2. Document Management System (DMS) - OpenKM: - Extensive experience in developing workflows, automations, cron tasks, and integrations using the Java/PHP API. - Configuration of daily backups. - Skilled in utilizing OpenKM as a DMS. 3. Algorithms and Programming: - Strong command over algorithms and programming skills, particularly in C/C++ and Java. - In-depth knowledge of data structures, strings, sorting, arithmetic and algebra, combinatorics, number theory, backtracking, graph traversal, algorithms for graphs, dynamic programming, and computational geometry. 4. Accounting: - Well-versed in managing material movement between stores and shops. - Proficient in handling retail-related accounting tasks. 5. Point of Sale (POS) Area: - Experience in integrating POS software with label printers, fiscal printers, barcode readers, fingerprint scanners, and keyboards.
    vsuc_fltilesrefresh_TrophyIcon Java
    Core Java
    Microsoft Excel
    Document Management System
    API
    Algorithm Development
    Data Structures
    API Development
    Hibernate
    Object-Oriented Programming
    .NET Framework
    MySQL
    Desktop Application
    C++
  • $50 hourly
    Native Android Developer | Java & Kotlin 🚀 Top Rated Plus 💯 100% Job Success Score 8+ years of experience working on native Android applications for high profile clients and businesses. I've strong Java/Kotlin programming skills including low-level performance optimizations and memory management. ✔ Ml-kit, OpenCv, TensorFlow, Camera, Image Processing ✔ Clean Architecture, MVVM, Firebase, Coroutines, Live data, DataBinding, Dagger2/Hilt, Room, Retrofit, Glide, Payments 🚀 Why Choose Me? 8+ Years of Servicing High-Profile Clients Strong Java/Kotlin Programming Skills Developer with a Keen Eye on Technological Advancements Detail-Oriented and Timely Deliveries
    vsuc_fltilesrefresh_TrophyIcon Java
    Android App
    Android Studio
    Native App Development
    Firebase
    Android App Development
    Kotlin
    Android
    Mobile App Development
    SQLite
    Camera Operation
    NFC
    Mobile App
    Android SDK
    OpenCV
  • $100 hourly
    I am a software engineer with 20 years of experience in multiple industry. I am a very passionate and an excellent problem solver. I work with Java 11 using Spring, Elastic Search, Jersey, Hibernate, Postresql , Mysql and ActiveMQ. I also have a lot of experience in AWS services such as Cloudformation, DynamoDB, Lambda, SQS , RDS. I have the AWS developer associate certification.
    vsuc_fltilesrefresh_TrophyIcon Java
    PostgreSQL Programming
    Linux System Administration
    Apache ActiveMQ
    Amazon Elastic Beanstalk
    AWS Lambda
    Hibernate
    Oracle Database
    Docker
    RESTful API
  • $40 hourly
    Creative back-end developer dedicated to building elegant solutions that meet business demands. Over 10 years of experience developing software of different scales ranging from small startups to large enterprise applications. Implemented back-end as well as front-end with the main focus on the former. Good communication skills proven through work experience in distributed team projects. 𝗕𝗮𝗰𝗸-𝗘𝗻𝗱 𝗧𝗲𝗰𝗵𝗻𝗼𝗹𝗼𝗴𝗶𝗲𝘀: Java, Kotlin JavaEE, Spring, Guice JDBC, JPA, Hibernate JUnit, Mockito, Cucumber, FitNesse Maven, Ant Git, SVN Jenkins, Sonar TypeScript, JavaScript Node.js Jest Webpack 𝗗𝗮𝘁𝗮𝗯𝗮𝘀𝗲𝘀: MySQL, MariaDB, Oracle MongoDB, AWS DynamoDB 𝗖𝗹𝗼𝘂𝗱 𝗣𝗿𝗼𝘃𝗶𝗱𝗲𝗿𝘀: Amazon Web Services 𝗦𝗲𝗮𝗿𝗰𝗵 𝗘𝗻𝗴𝗶𝗻𝗲𝘀: Solr, AWS Elasticsearch 𝗙𝗿𝗼𝗻𝘁-𝗘𝗻𝗱 𝘁𝗲𝗰𝗵𝗻𝗼𝗹𝗼𝗴𝗶𝗲𝘀: Vue HTML, CSS, Bootstrap Should you need any further information, please do not hesitate to contact me.
    vsuc_fltilesrefresh_TrophyIcon Java
    Distributed Computing
    Node.js
    Microservice
    Amazon Web Services
    NoSQL Database
    Spring Framework
    TypeScript
    JavaScript
    SQL
    MongoDB
  • $75 hourly
    I am a professional software developer with 25 years of experience. I focus on mobile app development for Android and iOS, web development, and cloud services. Throughout my career I have gained experience in many different technologies, from modern cloud, mobile, and web development architectures all the way back to mainframe systems. My app development experience includes location services, map integration, user authentication and user profile management, payment functionality, media playback including both audio and video, and in-app purchases. I can work with many services available from Amazon Web Services (AWS) and Google Cloud Platform (GCP). I am committed to producing a quality product. I always stand behind my work and communicate as much as I can. The more my client and I both know about what is being done, the happier everyone is.
    vsuc_fltilesrefresh_TrophyIcon Java
    ChatGPT
    Google Cloud Platform
    User Profile Creation
    Location-Based Service
    Firebase
    Amazon Web Services
    Node.js
    Kotlin
    Swift
    iOS Development
    iOS
    Android App Development
    Android
    Mobile App Development
  • $20 hourly
    🌟 Top-Rated Upwork Professional 🧑🏻‍💻 9+ years of experience 📱 Android | Kotlin | Java | Jetpack Compose | Kotlin-Multiplatform| Flutter | WearOS | AndroidTV | 🚀 AI | ChatGPT | 💻 Firebase | VoIP | Linphone With over 9 years of extensive experience as an Android Developer, I specialize in native Android application programming with a strong focus on SCRUM/Agile workflow. 
 
I have a proven track record of delivering high-quality mobile applications in various domains, including:
 * Airline Domain * Banking Domain * Cargo Management Domain * Logistics Domain * Financial Domain * Social Media/Dating Domain with Video/Audio Chats * Location Tracking Domain
 My expertise in mobile development includes:
 * Programming Languages: Java, Kotlin * Architectural Patterns: MVVM, MVP, MVC * Design Patterns, Custom Controls, and REST API integration * Material Design, Mobile UI/UX, and Firebase integration (AdMob, Analytics, A/B testing, etc.) * Jetpack Compose, Jetpack Navigation * Firebase Realtime Database and Storage * Android SDK, NDK, Open Source, Support Libraries * Reactive Programming with rxJava and rxAndroid * Dependency Injection using Dagger, Kodein, and Hilt * Databases: SQLite, Room, Realm, Page * Network Libraries: Retrofit, OkHttp, Volley, ktor * Image Loading Libraries: Picasso, Glide * Crash Reporting and Analytics Tools: Crashlytics, Firebase, Fabric, LeakCanary, Timber * Other Libraries: Gson, AutoValue, JodaTime, AndroidJob, Google Services * Sockets/SignalR * Kiosk Mode * SonarQube code coverage * Kotlin-Multiplatform (One POC)
 * Wear OS & Smartwatch development * Mqtt In addition, I am an expert in the Linphone SDK, a powerful tool for building voice and video communication applications. I have in-depth knowledge of integrating and customising the Linphone SDK to create high-quality, real-time voice and video chat functionalities within Android applications. I am experienced in implementing Linphone's advanced features, including call management, audio/video codecs, encryption, push notifications, and more. Whether you need to develop a VoIP application from scratch or enhance an existing app with Linphone capabilities, I can provide the expertise you require.
 I have integrated various features and technologies into Android applications, including:
 * Beacons integration for proximity-based interactions * Calendar API integration for managing events and schedules * QR Code integration for scanning and processing QR codes * OCR (Optical Character Recognition) integration for text recognition and extraction
 For multimedia capabilities, I have integrated Video Chat using WebRTC, ZegoClould, Twilio, and Agora, as well as Audio Streaming. I am familiar with ExoPlayer for HLS Video Streaming (HTTP Video Streaming), RTSP Video Streaming, and DASH Video Streaming.
 Other skills and features I offer include Custom Calendar development, Media Gallery implementation, Background Download and Upload functionality, Tiff file format handling in Android, Live Streaming using Agora and ZegoCloud SDK, Deep Linking, LeakCanary for memory leak detection, and code annotations to improve the linting process.
 Experienced Kotlin Multiplatform Developer with a track record of delivering efficient cross-platform solutions. Proficient in Kotlin Multiplatform Mobile (KMM) and skilled in creating high-performance apps for Android, iOS, web, and more. Experienced Jetpack Compose Developer, proficient in creating dynamic, interactive, and modern Android UIs. Skilled in leveraging Jetpack Compose's power to build visually stunning and responsive applications. Over the years, I have developed many different types of iPhone and Android apps. These include: - Food delivery apps - On-demand apps - Home services apps - Handy man apps - Salon apps - Beauty apps - Taxi apps - Ride apps - E-commerce apps - Dating apps - Health and fitness apps - Travel apps - Video streaming apps - Fintech apps - Shopping apps - Telemedicine apps - Finance apps - Real estate apps - Social media apps - Chat apps - Business apps - Messaging apps - Online courses apps - Online education learning apps - Tutor apps - Hotel booking apps - Online grocery order apps - Telecommunication apps - VoIP apps - SIP Apps - Apps using the Twilio API I am fluent in English and passionate about Android development. Please feel free to reach out to me with any Android-related questions or projects. I would be pleased to help you bring your ideas to life.
    vsuc_fltilesrefresh_TrophyIcon Java
    Mobile Device Management Software
    AOSP
    Smartphone
    iOS Development
    User Authentication
    Android
    JetPack
    Mobile App Development
    Wear OS
    In-App Purchases
    VoIP
    Firebase
    Android App Development
    Kotlin
  • $20 hourly
    I'm java full-stack developer with 4 years of experience. What I like most about programming is being able to provide solutions to seemingly complicated problems. Also, I am passionate about learning new technologies. I have experience working with technologies such as Java, angular , react, css, JS.
    vsuc_fltilesrefresh_TrophyIcon Java
    Node.js
    TypeScript
    Jest
    Redux
    Storybook
    React Bootstrap
    Front-End Development
    React
    Bootstrap
    CSS
    JavaScript
    HTML
  • $40 hourly
    Hello, I am Tarik Mujčić, a Full-Stack Software Developer with a strong focus on Java and Angular. Got a challenge ❓ I've got the solution ✅ I specialize in developing, fixing, optimizing, and delivering high-quality software solutions that streamline processes, enhance user experience, and provide reliable results. My goal is to create software that is both robust and user-friendly, effectively meeting your business needs with efficiency and precision. I am committed to delivering solutions on time ⌛, ensuring your project stays on track and achieves success 🎯 Skills and technologies I'm proficient at: ✅ Java/JEE, JavaFX ✅ Spring (MVC, AOP, Data, Security, Reactive...), Spring Boot ✅ Maven, Gradle ✅ JDBC, Hibernate ✅ TypeScript, Angular, HTML, CSS ✅ Database design and implementation ✅ PostgreSQL, MySQL, MSSQL, OracleSQL ✅ CI/CD tools (Jenkins, Nexus, GitHub actions, GitLab pipelines) ✅ Unit & Integration testing (JUnit, Mockito, Jasmine,...) ✅ REST APIs Feel free to reach out if you have any questions or would like to discuss how I can help with your project. I look forward to collaborating with you!
    vsuc_fltilesrefresh_TrophyIcon Java
    CSS
    HTML
    API Development
    Angular
    C
    Database Management System
    Hibernate
    Desktop Application
    RESTful API
    Spring Boot
    Database
    RESTful Architecture
    MySQL
    PostgreSQL
  • $75 hourly
    I am a highly experienced Java developer with 20 years of industry experience and I have been specializing in implementations using Adobe Experience Manager (AEM) for the past 9 years. I've built solutions in AEM 6.1 - 6.5 and AEMaaCS. In 2018, I was one of the winners of the Adobe Immerse 2018 Community Code Contest, as well as a presenter at the Adobe Immerse virtual conference, leading a discussion on Creating Custom ContextHub Stores and UI Modules in AEM. I have also contributed to ACS AEM Commons (the main AEM open source project) by helping to build Shared Component Properties. I also have solid experience working with various JavaScript frameworks like jQuery and VueJS and the drive to pickup new ones when necessary. I am also familiar with Less, SCSS, and CSS and the concepts of building responsive sites using Bootstrap and AEM Grid. I strive to write clear and maintainable code, and fully document my code to ensure future developers have a clear understanding of all methods and classes. Also, I will gladly provide any additional documentation or training materials requested, which will be well structured and well written. I am a strong problem solver and skilled at exploring and debugging complex problems to get software applications back on track when strange errors or edge case scenarios arise.
    vsuc_fltilesrefresh_TrophyIcon Java
    NodeJS Framework
    Adobe Experience Manager
    Vue.js
    Spring Framework
    CSS
    JavaScript
    Jakarta Server Pages
    HTML
    Java Servlet API
    jQuery
  • $40 hourly
    Experienced Senior Data Engineer | AWS, Big Data, and Cloud Solutions Specialist With over 8 years of experience as a Senior Data Engineer, I specialize in designing and implementing scalable data solutions across cloud platforms such as AWS and GCP. I have a proven track record in optimizing complex data pipelines, schema enforcement, and managing large-scale ETL processes. Skilled in Clickhouse, AWS Glue, Athena, Lambda, BigQuery, and Snowflake, I bring expertise in data architecture, cost reduction, and workflow automation. I'm passionate about delivering data-driven insights and leveraging cloud technologies to streamline processes for businesses. Let's collaborate to build efficient, scalable, and cost-effective data solutions!
    vsuc_fltilesrefresh_TrophyIcon Java
    GIS
    Parquet
    ClickHouse
    Snowflake
    Data Warehousing & ETL Software
    AWS Lambda
    AWS Glue
    Data Science
    API Integration
    Machine Learning
    SQL
    JavaScript
    Python
  • $49 hourly
    ✨ Algorithm & Software Engineering Expert | OR & ML Specialist ✨ * Highlights & Achievements: • ICPC World Finals 2022 Competitor — Ranked in the top 2% out of 58,000+ global contestants. • Codeforces Master (Top 1%) — Maximum rating 2221, consistently solving complex algorithmic challenges. • 10–15% Profit Boost — Optimized airline scheduling with metaheuristics (Genetic Algorithms, Local Search). • 2nd Place in Huawei Challenge Hackathon — Engineered high-performance algorithms under tight deadlines. * What I Offer: • Advanced Algorithms & Optimization: Deliver efficient, scalable solutions using heuristics, metaheuristics, and classical OR techniques (e.g., LP/IP, Graph Theory). • Machine Learning & Data Science: Proficient in Python, TensorFlow, and PyTorch, turning raw data into actionable insights. • Clean, Maintainable Code: Rigorous coding practices (version control, testing, CI/CD) for reliable, future-proof software. • Problem Solving & Collaboration: Translate ambiguous requirements into tangible solutions—fast turnaround, thorough communication. * Education & Background: • B.Sc. in Computer Science (Data Science focus) — Innopolis University. • Hands-On R&D experience at Optifly (airline scheduling software) and Huawei (reinforcement learning framework). I’m here to help you tackle complex projects, streamline operations, and push your product to the next level. Ready to collaborate? Let’s turn your ambitious ideas into outstanding results!
    vsuc_fltilesrefresh_TrophyIcon Java
    MetaTrader 5
    Operations Research
    Computer Science
    Heuristic Evaluation
    Performance Optimization
    Algorithm Development
    Linear Programming
    Mathematical Optimization
    Data Structures
    C++
    Python
  • $30 hourly
    10+ Skills | 15+ Years experience in Engineering field Android, Java/Kotlin/Python/C/SQL, UI/UX, Git, GitHub/GitLab/Bitbucket, Android Studio/IntelliJ IDEA/Eclipse, Trello/GitLab board, SOLID Firebase, Bluetooth and much more - developing projects from scratch (setup, architecture, features development) - deveopment for embended devices - support legacy projects - integration of new technologies - working with Google guidelines I can just do any job for you, no matter how difficult the task you describe I do
    vsuc_fltilesrefresh_TrophyIcon Java
    Firebase
    Coroutine
    Retrofit
    Android Studio
    SQLite
    Kotlin
    Android App Development
    Mobile UI Design
  • $105 hourly
    ** HubSpot Design Certified ** Recently recognized as a HubSpot Champion User Worked on many different types of applications and with many different technologies. Quickly learn new programming languages and technologies. Can also read and understand existing code to find and fix bugs. Have 26 years experience in IT. Have a Bachelors Degree in Math as well as an MBA. I have worked with many programming languages including COBOL, Visual Basic, C, C++ and Java. Currently working on projects utilizing Angular, JQuery, Java Script, CSS, HTML5, Hubspot and Flex. I am familiar with content management systems. I have worked on front end designs/pages and back end services. Have done responsive development, desktop applications, and mobile applications.
    vsuc_fltilesrefresh_TrophyIcon Java
    CSS
    HTML
    Content Management System
    HubSpot
    CMS Development
    Website Customization
    Agile Software Development
    Blog Development
    Inbound Marketing
    Templates
    Business with 100-999 Employees
    iOS Development
    Android App Development
    JavaScript
  • $35 hourly
    ON TIME, ON BUDGET, HIGH QUALITY APPS Almost any app you need I can create it, fix it, improve it for you. Good Communication, easy to work with, enthusiastic, perfectionist. 5+ years of experience Prototyping & Concept Development Worked in complex apps fixing bugs, cleaning the code, etc. SDK NDK JAVA C Image Processing Photo Editor Games Camera AdMob Algorithms Optimization for speed and small apk size ETC. Attention to detail Perfectionist
    vsuc_fltilesrefresh_TrophyIcon Java
    JetPack
    Chromium
    Android App
    Android NDK
    Android SDK
    Kotlin
    C
    Bluetooth
    Android
    In-App Purchases
    Software Architecture & Design
    Android Studio
    Linux
  • $120 hourly
    10 years of experience working on native Android applications for high profile clients and businesses. 100% Job Success | 11,000+ Hours | Top Rated Plus | 5 Star Reviews Exclusively From planning, developing and publishing to maintaining and supporting high quality Android applications. I hope you see the experience displayed in my profile as an indication of my reliability. ✔︎ Constantly updating my knowledge with the most recent design patterns and code conventions; ✔︎ The delivery of a product that respects the highest standards of usability, performance and appearance is guaranteed; ✔︎ Great cost-benefit by delivering faster and higher quality products than the average; ✔︎ Flexible availability to always meet the client's needs. Vast experience managing development teams located in different places around the world. As an example, I've been managing a team that averaged 7 developers located in different countries, such as Canada, Ukraine, Pakistan, India and Brazil. ✅ Mobile Development Leader; ✅ Native Development; ✅ Kotlin and Java Expert; ✅ Clean code, DRY and KISS principles; ✅ Unit and automated testing; ✅ Well documented code; ✅ UI/UX Best Practices; ✅ NoSQL and SQL Databases; ✅ API Integration; ✅ Web Services Development. MySQL, SQLite, PostgreSQL, SQL Server, Firebase, Java, Kotlin, Android Studio, Android SDK, Android NDK, Device Owner, Play Store...
    vsuc_fltilesrefresh_TrophyIcon Java
    RESTful Architecture
    Android
    MySQL Programming
    Material Design
    Android SDK
    SQLite
    PHP
    Firebase Cloud Firestore
  • $46 hourly
    I am a tech enthusiast and Software Engineer with +7 years of experience in several fields. - Front-end experience: Flutter - Back-end experience: Firebase, Java, Node.js, C#, Ruby on Rails I am the co-founder of a Flutter Agency (SmartUp Software) in which we provide custom software development and staff augmentation services, having developed and deployed 10+ apps/webs. I developed an award-winning social project called "Berrinche" whose main purpose is to help parents and therapists of those with ASD to discover the causes of disruptive conduct and how to treat them.
    vsuc_fltilesrefresh_TrophyIcon Java
    pandas
    Microsoft Power BI
    Python
    Dart
    In-App Search
    Node.js
    Ruby on Rails
    CSS
    HTML
    C#
    Android
    Angular
    JavaScript
    Flutter
  • $25 hourly
    I have 6 years of working experience in the software industry, and I am confident most as a Backend Developer and Data Engineer. For now, I want to spend more time on the freelance path, to help others solve their problem happily. As a backend developer: - I build microservices using Java and Go - I design a Database schema for features I work on. - I write REST API and work with the frontend team for integration. As a data engineer: - I do ETL tasks. - I write batch jobs and real-time jobs for streaming over 50 GB of data per day. - I store processing data into HBase, MySQL. - I visualize data to make it meaningful to others. Besides, I also spend time playing with frontend stuff such as NextJS, VueJS, CSS. Availability: My time zone is GMT+7, but I am flexible on working time, even at midnight. If you want to work with me for more than 30 hours, just say it, I will consider working more. Let’s work together to turn your idea into reality!
    vsuc_fltilesrefresh_TrophyIcon Java
    RESTful API
    Database
    Database Architecture
    Git
    Apache Kafka
    Spring Framework
    Apache Spark
    PostgreSQL
    Golang
    Scala
    JavaScript
    Python
    Redis
  • $25 hourly
    I am having 6+ year of hands on experience on working with both frontend, backend technologies and complete Software Development Life Cycle. I have worked with various technologies to develop web , desktop solutions and live streaming of data.
I have specialised in developing rich web applications in J2EE using hibernate and spring framework,I'm even experienced in open source software solution like Dspace (Use digitalis document) and Vufind there installation,customization etc Experience with dspace like -DSpace Domain Knowledge -Dspace Installation on cross platforms. For frontend, I have hands-on experience on 1)Bootstrap, 2)Javascript, 3)Jquery, 4)HTML5, 5)CSS3, 6)AngularJS 7)Jquery Mobile 8)Angular For backend, I have hands-on experience on 1)Java 2J2EE 3)Hibernet 4)Spring 5)Maven 6)Ant 7)Nodejs 8)Socket.io 9)Express For Source Control, I am familiar with SVN and GIT. I have experience on working with any third party API integration using XML, SOAP, JSON and JSONP. I am hardworking and passionate for my work. I always strive to surpass customers expectations, providing highest quality solutions within budget and the allocated timeline.
    vsuc_fltilesrefresh_TrophyIcon Java
    MQTT
    DICOM
    Medical Imaging
    Linux System Administration
    Socket.io
    Spring Boot
    Spring Framework
    jQuery
    Hibernate
    React
    Angular
    Node.js
  • $50 hourly
    I'm a full stack software developer with experience in Java and Android projects. I focus on service and delivering the best experience to my clients, while providing quality software on a timely fashion. I have experience with various technologies to help fulfill any kind of job. I'm also open to having a chat with my customers, if they so desire, so we can arrange any details about the job. I also have experience with Cyclos Banking System Software, providing consultant services to small-medium banks. I've done several integrations with 3rd parties software with it, also developed plenty of aditional feature for it too, like bank statements and import of payments. I have experience on the following languages and technologies: -Java: Everything enterprise, Servlets, JSF, Primefaces and JPA. -JavaScript: pure Script, NodeJS and AngularJS. -PostgreSQL, SQLServer, SQLLite I also have experience providing products and solutions for financial institutions. My biggest desire is to serve my customers as if it was me requesting the product, I always strive to deliver the best software since I wouldn't settle for less.
    vsuc_fltilesrefresh_TrophyIcon Java
    Email Campaign Setup
    J2EE
    Android App Development
    Microsoft SQL Server Programming
    API Development
    MySQL Programming
    Java Servlet API
    JavaScript
  • $70 hourly
    ★ Product owner of StatHero(iOS and Android apps, Angular web app), with thousands of daily active users ★ Created the StoryChimes brand (mobile app on iOS and Android), achieving over 7 million downloads ★ Created mobile apps based on the Lennon/McCartney catalog with Sony/ATV Music Publishing ★ Released key music apps for Imagine Dragons, R5, and LeAnn Rimes ★ Released several games that achieved over 10 million downloads ★ Led the development of over 200 mobile apps (iOS and Android) and 100 websites ★ Led the development of numerous blockchain projects, including crypto launchpads, NFT marketplaces, decentralized exchanges (DEX), wallets, GameFi platforms, and metaverse developments ★ Led the development of over ten early-stage AI startup projects ★ Third-party clients included Intel, Crispin Porter + Bogusky, Samsung, and HarperCollins Hello, I'm Nick, the wizard behind the curtain at several software development companies. With a wand made of code in one hand and fifteen years of magic tricks up my sleeve, I lead a troupe of highly skilled digital artisans. 🙌 Wondering how one person can be a specialist in mobile, web, game, AI, and blockchain development? Well, you learn a few spells when you've been around the tech block as long as I have. 🧙‍♂️ As the product owner and head wizard at StatHero, a leading disruptor in the daily fantasy sports space for real cash gaming, I've grown the company into a multi-million dollar business. 💰 But what truly sets me apart is my unwavering optimism and knack for finding solutions where others see dead ends. No matter the challenge, I see it as another opportunity to innovate and excel. 😉 I believe in the power of team magic. Alone, one might not change the world, but with a dev force like ours, we're not just making apps; we're making history. Need a software solution? Just say the word, and my team will bring your vision to life - like pulling a rabbit out of a hat! 🎩 Bonus Profile: My Life Before Code 🎁 Before I dove into the digital world, my creative energies found their outlet in other forms. I wrote and produced a film titled The Cook in 2008, exploring storytelling through cinema. Even earlier, for thirteen years, I played the trumpet, embracing the world of music and performance. For 18 years, as an executive at two Hollywood studios and working in music, these experiences shaped my understanding of teamwork, creativity, and perseverance, enriching my approach to technology and leadership.
    vsuc_fltilesrefresh_TrophyIcon Java
    Game Development
    Web Development
    Blockchain Development
    iOS Development
    Flutter
    Swift
    Angular
    React Native
    Android App Development
    Kotlin
    JavaScript
    PHP
    Mobile App Development
    React
  • $45 hourly
    I am a Java Web Developer, working as freelancer, mainly in Upwork. I am very passionate with Java and JVM technologies. My experience mostly in developing Software As A Service (SaaS) platform, business computing and information system area, using Bootstrap, Angular JS or JSF as UI Components or web framework, Spring Core, Spring MVC or JBoss Seam as Restful API endpoint and or Integration framework, and Hibernate as favorite Java Persistence API (JPA) implementation wrapped by Spring Data component. If my clients requires no casual application or web server, I like to use Spring Boot for simpler development and deployment of the application. I am also interested in database design and software design. I believe that great software not only mediocre work of typing, but also comes from thoughtful process. I believe in TDD, and also believe that tests code must be written, organized as good as the source code it self and is integral part of the source code. I am a quick learner, and In my spare-time, I am writing some personal open source project and small proof-of-concept about java-related stuff in my GitHub public repository. My primary machine is linux desktop with 1TB NVMe SSD and 64GB or RAM. I have macbook pro 15 for testing purpose and to allow me mobile occasionally, if needed. Communication is important in remote work, and for this purpose I have 2 link dedicated internet connections to my workspace. If you need my detailed skill abilities, below is what I have experienced in: - Software Design, Database Design, and microservices/Micro-services/micro services architecture. - JPA 1.0, JPA 2.0, with Hibernate. - Bean Validation Specification with Hibernate Validator. - Dependency Injection with Java DI (JSR-330), Java Context and Dependency Injection for Java EE Platform (JSR-299), and Spring Core as most popular (but non-standard) Java Dependency Injection Framework. - Java Web Framework with Spring MVC and JSP, or Java Server Faces (JSF) with Facelet and Primefaces. - Spring Boot, Spring Data stack. - Generated / scaffolding web application using JHipster. - Java Web / Application server with Tomcat, Wildfly, or Websphere AS. - Logging with SLF4J as a wrapper to Log4J or Logback. - JUnit or Test NG as testing framework. - Ant, Maven or Gradle as build and dependency management tool. - HTML 5, CSS 3, JavaScript, JQuery, Twitter Bootstrap, transparency.js, and angular / angular.js - Third Party API such as Xero API, Open ERP Java API, Braintree Payment API, Stripe Payment API, and Social APIs. - Linux, Mac or Windows. - MySQL, PostgreSQL, Oracle, or Microsoft SQL Server for RDBMS. - Couchbase or Mongo DB for No-SQL solution. - Elasticsearch (ELK) stack or pentaho for data integration, advanced search, reporting and data analysis solution. Thanks, Resa
    vsuc_fltilesrefresh_TrophyIcon Java
    Spring Framework
    Angular
    Spring Data
    DigitalOcean
    Spring Boot
    Hibernate
    JHipster
    Java Persistence API
    Amazon Web Services
    Web Service
    SQL
    JavaScript
  • $50 hourly
    I’m a programmer with more than 10 years of experience who can work in different programming langauges using different frameworks. I can create any application type: ● web based ● desktop If I don’t know any programming language or framework which you want to use to build your application then I can learn it in couple days. SKILLS ● PHP ● Javascript ● jQuery ● Bootstrap ● AJAX ● MySQL/PostgreSQL ● REST API ● HTML/HTML5 ● CSS/CSS3 ● C/C++ ● Ruby (and framework Ruby On Rails) ● Python ● Java ● CUDA Computation ● OCR (on C/C++, Python, Java) EXPERINCE ● Freelance 5+ years (up to July 2014). I was working hard to learn what clients want to see, to learn different programming languages and frameworks. Those years taught me to learn new things everyday to provide high-quality solutions for my client. Here's some of my works (PHP, MySQL, HTML, CSS, JavaScript): ○ dev.louepartout.com ○ kilosolution.com ● Swiss Interactive Software GmbH (August 2014 - December 2014). Front-End and Back-End developer for gambling platform and websites (using the platform). Here's you can see some of the websites we built (PHP, MySQL, HTML, CSS, JavaScript, Bash): ○ betboro.com ○ sports.flutterclub.com ○ sports.princessstar.com ○ globalbet.eu ● Ad.net (February 2015 - Present).
    vsuc_fltilesrefresh_TrophyIcon Java
    HTML5
    CSS 3
    C++
    MySQL
    React
    Bot Development
    Automation
    Data Scraping
    Python
    PHP
    Data Extraction
    Web Crawling
    JavaScript
    Selenium
  • $55 hourly
    Hi, I’m an Android developer with over 10 years of experience in building native applications. I work with a modern tech stack, including Android Jetpack, Kotlin Coroutines, Jetpack Compose, MVVM, and Dependency Injection (DI). I also have experience with cross-platform development using Flutter/Dart and Kotlin Multiplatform. Key Expertise: • Audio/Video Calls: WebRTC integration for real-time communication. • In-App Purchases and Google Play Billing. • Machine Learning: On-device ML with TensorFlow Lite, ML Kit. • Geolocation and Firebase Services (e.g., FCM, Crashlytics, Analytics). • Media Processing: Photo, video, and audio. • Platform Migration: Converting iOS/web apps to Android. I’m skilled at integrating third-party APIs, working with CI/CD pipelines, and implementing modular architectures for scalable and testable code. I’d love to help bring your ideas to life, from early-stage concepts to full-scale app solutions. Feel free to reach out! Thanks, Oleksandr Ilchuk
    vsuc_fltilesrefresh_TrophyIcon Java
    Android SDK
    Mobile App Development
    Android App Development
    Firebase
    Smartphone
    Android
    Flutter
    Kotlin
  • $30 hourly
    I have 12 years experience in software development. My technology stack are as follows: - VueJS/Next.js/React/React Native/Astro - TypeScript - NodeJS - PHP - Custom/Laravel - TailwindCSS - Bootstrap - JQuery - Docker - CI/CD - Github Actions - Serverless - AWS Services - Server Management - Ubuntu & Windows - Shell/Bash Scripting (deployment automation) I am keen to details, and I work hard to provide beyond expectations. Let's work together.
    vsuc_fltilesrefresh_TrophyIcon Java
    Docker Compose
    AWS CloudFormation
    Amazon ECS
    AWS Lambda
    Next.js
    React
    CircleCI
    PHP
    Vue.js
    Laravel
    Amazon Web Services
    Docker
    JavaScript
    Node.js
  • $15 hourly
    #AndroidDeveloper I graduated from GC University with a degree in Computer Science in 2019 and have been working professionally as a Android developer since 2018. I developed more than 50 apps and also worked as a team lead in Idealogic software house.
    vsuc_fltilesrefresh_TrophyIcon Java
    Android SDK
    Laravel
    Android
    Kotlin
    Android App Development
    Node.js
  • $35 hourly
    Hello there! If you’re looking for a reliable Senior Android developer, you are on the right page. I'm a seasoned Android developer, crafting reliable, fast, and top-notch apps. Global projects across varied domains have honed my skills and enriched my tech arsenal. 🛠 Key skills: 📎 Kotlin & Java: My trusty languages. 📎 Android SDK & Jetpack: Foundation of my work. 📎 SQL, Rxjava, Retrofit2: Tools for data and communication. 📎 Firebase & Git: Ensuring smooth workflow. 📎 MVVM, MVP: My guide for structuring apps. 📎 Design Patterns, In-app Billing, Google Maps: Enhancing user experience. 🤝 I value clear, SMART communication and deadlines, making teamwork a breeze. Ready to dive into new challenges and eager to learn, so drop me a line with your requirements. Let's create digital wonders! 📲 _____________________ * Need a wider range of services? No worries, you are on the right path anyway. I'm working in association with the 90-person-strong TOP Rated Plus Agency - PECODE. You can count on us if you need experts in UX/UI design, Mobile app development, Quality Assurance ( manual & automation). We will support you at each stage of development: 🥇 Before the start we provide you estimates based on project requirements analysis and specification 🥇 Take care of the web product's development from needs to production 🥇 Support and improve the product after realise. Since 2017 we bring client's ideas into reality, and we are looking forward to starting the collaboration with you!
    vsuc_fltilesrefresh_TrophyIcon Java
    Google Play
    Git
    RxJava
    Dagger 2
    Android SDK
    API Integration
    Map Integration
    Smartphone
    Tablet
    Kotlin
    Location-Based Service
    Android App Development
    User Authentication
    Native App Development
  • $35 hourly
    Do you want to turn your idea into an IT project? 𝐋𝐞𝐭’𝐬 𝐠𝐞𝐭 𝐚𝐜𝐪𝐮𝐚𝐢𝐧𝐭𝐞𝐝.:handshake: Hello, my name is Darko Kiparizovski, I am Senior Developer at 𝐃𝐚𝐭𝐚𝐎𝐱, a leading company in the Comprehensive Software Development sector. I am thrilled you’re considering us for your project, and I’m confident our team have the skills, expertise, and experience to deliver outstanding results. 📌 Our Offerings • End-to-end custom software development ➖ You’ve got ideas, we’ve got solutions. • Automation ➖ Automated solution from existing business process. • Data services: scraping, extraction, processing ➖ Any data. Any size. Anywhere. • SaaS and Web Development ➖ From the idea to the first subscriptions. • Dedicated Crew ➖ An extension of your in-house team. • Guarantees ➖ Dependable solutions, timely delivery, and steadfast support. 📌 Why Choose 𝐃𝐚𝐭𝐚𝐎𝐱 • Absolute dedication - the ultimate goal is the client’s satisfaction. • Stress-free same-day communication with the top experts in the industry. • Relationship-centric approach - approximately 80% of our clients are returning customers. • In-depth engagement - increased involvement leads to superior outcomes. • Complete transparency - no unexpected surprises, remain informed throughout the process. • Going the extra mile - providing added advantages to exceed your expectations. • Proficient in English - eliminating language barriers for clear communication and timely execution. If these resonate with you, our team is poised to meet your needs! Feel free to schedule 𝙁𝙍𝙀𝙀 consultation with 𝗧𝗢𝗣 𝗘𝗫𝗣𝗘𝗥𝗧𝗦. Just contact us
    vsuc_fltilesrefresh_TrophyIcon Java
    Automation
    Web Crawling
    Full-Stack Development
    Data Scraping
    Social Media Chatbot
    Web Application
    OCR Algorithm
    ETL
    Discord Bot Development
    Social Listening
    Data Extraction
    Back-End Development
    Python
    Scrapy
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Java Developer Hiring Guide

What is a Java developer?

A Java developer is a professional software engineer specializing in the Java programming language. These experts use their skills in application development, object-oriented programming (OOP), and Java frameworks like Spring Boot and Hibernate to create web applications, android apps, and enterprise-level software solutions. Java developers focus on writing efficient Java code and integrating APIs to deliver functional and scalable systems.

In addition to their technical expertise, Java developers collaborate with team members across the project lifecycle to ensure seamless execution. They use development tools like Maven, Jenkins, and Git, employing agile methodologies to deliver high-quality results. Their knowledge spans areas like algorithms, data structures, and dependencies, making them vital contributors to software development across industries.

Why hire a Java developer?

Hiring a Java developer is essential for businesses seeking to create or enhance Java applications. These professionals bring in-depth expertise in core Java, Java frameworks, and open-source tools, enabling them to develop customized solutions tailored to your needs. Whether you require a full-stack developer, a senior Java developer, or an entry-level Java developer with the skills to ensure the efficient execution of web development and back-end development projects.

Java developers also excel in problem-solving and troubleshooting, making them invaluable for optimizing performance and integrating new features. With certifications and experience in platforms like Oracle and GitHub, they are equipped to handle tasks ranging from quality assurance to implementing advanced automation systems. Their ability to integrate tools like REST APIs, JDBC, and DevOps ensures seamless connectivity and enhanced functionality for your applications.

How to hire Java developers

Hiring the right Java developer on Upwork is simple and efficient. Follow these steps to find a professional who matches your project needs:

  • Determine your project needs. Define whether you require expertise in Android development, web applications, or enterprise-level systems. Be specific about the Java frameworks and tools needed, such as Spring Boot, Maven, or Hibernate.
  • Create a detailed job post. Write a job description outlining your expectations, such as proficiency in OOP, algorithms, and SQL, and experience with development tools like GitHub and Jenkins. Include details about the lifecycle methodologies you prefer, such as agile or DevOps practices.
  • Review proposals. Evaluate candidates based on their certifications, portfolios showcasing Java applications, and familiarity with essential technologies like REST APIs, Linux, and Python.
  • Interview candidates. Discuss their experience with debugging, troubleshooting, and optimization. Ask about their ability to manage dependencies, integrate new features, and work collaboratively with team members.
  • Hire and collaborate. Select the best candidate, share your project requirements, and maintain open communication to ensure the successful delivery of your application.

How to write a Java developer job post

A strong job post is essential for attracting top Java developers to your project. Here’s how to write one:

  • Use a clear title. Titles like “Senior Java Developer for Web Application Development” or “Full Stack Java Programmer for Microservices Project” help set expectations.
  • Introduce your company. Share details about your organization, whether you’re a startup or an established company, and explain how the Java developer will contribute to your software development goals.
  • Define key responsibilities. Include tasks such as developing Java software, integrating APIs, and building scalable back-end development systems. Highlight the importance of skills like debugging, working with Java frameworks, and creating responsive user interfaces.
  • Specify required skills. Make a wish list of expertise in tools and technologies such as Spring Boot, Hibernate, SQL, and Maven. Mention knowledge of data structures as well as algorithms, and experience in DevOps. The role may require education, such as a bachelor’s degree in computer science.
  • Include project details. Provide details about the scope of work, timeline, and deliverables, such as creating new features, optimizing performance, or ensuring robust quality assurance processes. Share expectations around project-based or full-time positions.

Common Java developer services

Java developers offer a wide range of services to support your application development needs. Below are some of their most common services:

  • Web application development. Building scalable and dynamic web applications using Java frameworks like Spring Boot and Hibernate, paired with front-end technologies like HTML, CSS, and JavaScript for a responsive user interface.
  • Android app development. Designing feature-rich Android apps with seamless connectivity, advanced functionalities, and intuitive designs to meet user demands.
  • API integration and development. Creating and integrating REST APIs to enhance application functionality, ensuring smooth communication between systems.
  • Back-end development. Crafting robust server-side solutions using tools like Java EE, JDBC, and SQL to handle complex data operations efficiently.
  • Debugging and troubleshooting. Identifying and resolving issues in Java code to optimize system performance and ensure smooth functionality across platforms.
  • Optimization and performance tuning. Enhancing existing Java applications by improving code efficiency, database queries, and reducing system latency.
  • Automation and DevOps. Implementing tools like Jenkins and GitHub to streamline deployment, ensure continuous integration, and simplify lifecycle management.
  • Full stack development. Combining expertise in front-end and back-end development to deliver comprehensive solutions, from user-friendly designs to secure and scalable systems.
  • Consulting and training. Offering guidance on Java programming language, best practices in object-oriented programming, and effective use of development tools to enhance team capabilities.

FAQ

What skills should a Java developer have?

A qualified Java developer should have expertise in the Java programming language, object-oriented programming (OOP), and frameworks like Spring Boot and Hibernate. They should also be proficient in development tools like Maven, GitHub, and Jenkins, with a solid understanding of algorithms, data structures, and SQL. Experience with REST APIs, debugging, and optimizing performance is crucial for delivering high-quality results.

Can Java developers handle both front-end and back-end tasks?

Yes, many Java developers are skilled in full stack development, enabling them to work on both front-end and back-end development. They use technologies like HTML, CSS, and JavaScript to create responsive user interfaces and frameworks like Java EE and Hibernate to build robust server-side systems.

What industries commonly hire Java developers?

Industries such as finance, e-commerce, healthcare, and technology frequently hire Java developers for application development projects. Their ability to create scalable web applications, integrate advanced APIs, and optimize Java software makes them valuable across diverse sectors.

How do Java developers ensure high-quality code?

Java developers ensure quality by adhering to best practices in software development, performing thorough debugging, and following agile methodologies. They use tools like GitHub for version control, Jenkins for automation, and rigorous testing to maintain robust and reliable Java applications.

What tools and technologies are essential for Java developers?

Java developers rely on tools like Spring Boot, Hibernate, Maven, and Jenkins to streamline development processes. They often use Git for version control, SQL for database management, and REST APIs for seamless integration. Proficiency in Python, Linux, and DevOps tools further enhances their capabilities.

Hire a Java developer on Upwork

Hiring a Java developer on Upwork connects you with experienced professionals skilled in software development, Java frameworks, and building scalable systems. Whether you need help with web applications, android apps, or enterprise-level projects, you’ll find qualified developers to meet your needs.

Sign up for Upwork today, post your project, and collaborate with talented Java developers to bring your software ideas to life. With expertise in APIs, debugging, and advanced automation, these professionals ensure your success in the fast-evolving world of technology.

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