Hire the best Core Java developers
Check out Core Java developers with the skills you need for your next job.
- $15 hourly
- 4.7/5
- (52 jobs)
Over the last 14 years, I have almost completed 42 android projects for different businesses and personal use of my clients. Great experience in Java, Kotlin , Jetpack Compose, Dagger HILT and other architectural component, View Based Systems, Android SDK, Google's Android related service and Android Studio. I always welcome new ideas and love to convert them in smart android application. During different applications development period I have gone through many different challenges and finish all of them with my smart work. I have been work in all below area and also willing to explore more with new things. Material Design with backward compatibility, Jetpack Compose, Navigation Component, Dagger HILT, Paging 2 and Paging 3, SQL/SQLite databases, JSON Bese data parsing, RestFull Web service integration, Room, Audio/Video Streaming, ExoPlayer, Face Recognition and OCR, Social Network - Facebook, Twitter integration, Google Map and other Google services, Other open source library integration and modification according to requirement. I am familiar with MVVM,MVC and Clean architecture pattern. I have developed some of my apps with MVVM + CLEAN architecture, including all layers, such as Presentation, Data and Domain. I have hands on experience in Kotlin Flow, LiveData and Coroutine. I am cost effective but quality work provider.Core Java
JetPackFace DetectionAndroid Room PersistenceSQLiteFirebaseQR & Barcode ScannerKotlinMobile App DevelopmentAPI IntegrationApplication SecurityAndroid App DevelopmentUser AuthenticationIn-App Purchases - $27 hourly
- 5.0/5
- (127 jobs)
My area of expertise is an HCL Notes (formerly IBM Lotus) and MSOffice VBA. I have 24 years of Lotus Domino developing and administration: - administering of Lotus Domino server versions R6, R7, R8.5; R9; R12 - replications settings, mail routing configuration, mail troubleshooting; - application development; - excellent knowledge of LotusScript, @-Formula, Domino Object model; - MS office with Lotus integration, ODBC connection; - migration from Lotus(mail) into Google Apps using Google Tool (GAMLN); - developing application in Lotus which works with Google Docs; - creation REST api for Lotus database using webservices; - experience in creation of java Lotus Server Addins; 7 years of VBA macro development. Complex excel data manipulation is my passion. I provide development of Excel VBA macro - tasks of any complexity, starts from simple formatting and ending with (but not limited) processing of big data sets, data permutations and manipulations, export to/from formats PDF, Excel, Word, txt, CSV, XML, JSON, creation of Userforms. Data analysing tools in Excel, Adword Keywords/campaigns reorganizing and formatting, REST API's, Telegram Bot API, Google API's In case you have in Excel (or with csv, txt, word files) a very repetitive tasks - I can easely automate it and save your time and efforts. web data scraping. I can give you 100% accuracy when processing your data. I am hardworking and reliable.Core Java
Desktop ApplicationXMLC#XSDHCL DominoMicrosoft Outlook DevelopmentXSLTHCL NotesMicrosoft Excel - $25 hourly
- 5.0/5
- (15 jobs)
Experienced Full Stack Web Developer specializing in creating dynamic and responsive websites tailored to meet the unique needs of businesses. With a proven track record of delivering high-quality web solutions, I bring a blend of technical expertise and creative problem-solving skills to every project. Let me transform your ideas into visually appealing and functionally robust websites that drive results. Elevate your online presence with a developer who is passionate about crafting seamless user experiences.Core Java
DjangoFull-Stack DevelopmentBack-End DevelopmentFront-End DevelopmentWordPress WebsiteAPI DevelopmentCoding LessonMERN StackWeb DevelopmentPythonReact NativeHTML5Node.jsReactJavaScript - $40 hourly
- 4.5/5
- (9 jobs)
I’m a Software and Development Engineer, with 10 years of experience in the fields of Analysis, design, development of web applications and rich clients. With many skills in several languages mainly Java/JEE, I worked on multiple projects for large customers such as industrial or telecommunications or insurance companies. This allowed me to develop an expertise in the Development of java software. I am ready to take your project from the scratch and create a strong architecture, or support/refactor existing solution.Core Java
Azure DevOpsAWS LambdaSpring CloudHTMLWeb Services DevelopmentSpring FrameworkJavaJavaScriptDesktop ApplicationHibernateSpring BootCore PHPData Analysis - $30 hourly
- 4.8/5
- (13 jobs)
Skilled Mobile Engineer with more than 8 years of development experience. Started as an Android developer and then move to work with Flutter and deliver applications to both platforms. Core skills: Strong knowledge of Dart, Kotlin, Java Core, Flutter, Android SDK Good understanding of OOP principles, REST, JSON, design patterns, Android Jetpack tools Proficient in XML, SQLite, Git IDEs: Android studio, IntelliJ IDEA, NetBeans English – upper intermediate Industry aware, good problem solving skills Experince in working with third-party libraries: Retrofit, RxJava, Volley, Dagger2, Butter knife, Gson, GraphView, Retrofit, Picasso, Realm, Social networks integration( Facebook, Twitter, Instagram), Google Maps API, Youtube APICore Java
Google Maps APIObject-Oriented ProgrammingXMLJSONSQLite ProgrammingMaterial DesignAndroid SDKMobile App DevelopmentiOS DevelopmentFirebaseAndroid App DevelopmentDartFlutterAndroid - $40 hourly
- 4.9/5
- (49 jobs)
I’m Harmeet, an experienced Java Developer with over 10 years of expertise in building both web applications and mobile apps. Specializing in Java tech stack (Core Java, Spring Boot, Hibernate, and more), I craft scalable, secure, and user-friendly applications that help businesses achieve their goals. Whether it’s creating dynamic web platforms or high-performance mobile apps, I deliver solutions that are reliable, secure, and optimized for growth. My Core Competencies 1. Java Development: - Core Java: In-depth knowledge of Java’s features, collections, concurrency, and multi-threading - Spring Framework: Expertise in Spring Boot, Spring MVC, Spring Security - Microservices: Designing and implementing microservices architecture with Spring Cloud - API Development: RESTful APIs with JWT, OAuth, and GraphQL integration 2. Mobile App Development: - Android Development: Skilled in developing native Android apps using Java and Kotlin - App Lifecycle: From UI/UX design to API integration and deployment 3. Database & Back-End: - Database Expertise: Proficient in MySQL, PostgreSQL, and MongoDB for secure, scalable data management - ORM: Working with Hibernate for object-relational mapping - Server-Side Scripting: Building efficient backends with Java and Spring. 4. Deployment & Cloud: - Cloud Deployment: Expertise in deploying Java-based applications on AWS, Azure, and Google Cloud - Containerization: Proficient with Docker for application containerization and management 5. Security & Performance: - Application Security: Implementing secure systems with Spring Security, OAuth, and data encryption - Performance Tuning: Optimizing application speed, database queries, and server-side performance Industries I Serve - E-Commerce: Custom checkout systems, payment gateway integration, and scalable shopping carts - Healthcare: HIPAA-compliant mobile apps and backend systems for patient management - Finance: Developing secure and efficient transaction systems, real-time data processing - Education: Learning platforms and mobile apps to enhance educational experiences - Travel & Hospitality: Building booking engines, itinerary planners, and travel apps - Real Estate: Custom property listings, user-friendly property search apps Why Work With Me? - End-to-End Solutions: From ideation and development to testing and deployment - Scalable & Secure Architecture: Applications that grow with your business - Cross-Platform Experience: Expertise in both web and mobile development - Agile & Transparent Communication: Ensuring a smooth collaboration throughout the project Let’s Build Something Great! I’m passionate about using my Java expertise to build innovative, secure, and high-performing web and mobile applications. If you’re looking for a dedicated developer to bring your ideas to life, let’s connect!Core Java
SaaS DevelopmentFull-Stack DevelopmentWeb Application DevelopmentMobile App DevelopmentKotlinMongoDBMicroserviceRESTful ArchitectureAngularHibernateSpring BootSpring FrameworkJavaScriptJava - $45 hourly
- 4.5/5
- (104 jobs)
I'm a mobile app developer with a lot of experience in iOS and Android app development. I have been working with iOS and Android for 10+ years. ✅ Top Rated Plus ✅ 100% Job Success ✅ Building iOS and Android app from scratch to App/Play Store. I will be a premium asset for engineering your envisioned concepts and applications in terms of both consumers as well as enterprise applications. I have extensive experience in integration of third-party API like Facebook, Google, Twitter, Dropbox, Instagram, Amazon. I also have deep knowledge in developing custom backend solutions for interaction with mobile apps. Here are a few areas where I have worked: - Applications for Mobile, TV, Watches, Tabs, etc. - Material Design theme - Custom UI (need graphics) - Network communication - JSON/XML data formats - SOAP protocol - RESTful API design / Retrofit - Database (SQLite) / Caching algorithms - Working with Android default content providers (Contacts, Calendar, Media Store, etc.) - Hardware components (Camera API, Video/Audio processing) - Sensors (accelerometer, orientation, gyroscope, etc.) - Location API - Geolocation (GPS, network cells) - Activity recognition (still, walking, cycling, and in-vehicle) - Maps (Google Maps V2, OpenStreetMap, YandexMapKit libs) - Connectivity - Wi-Fi, p2p connections with Wi-Fi Direct - Bluetooth API - NFC (Near Field Communication) I am looking for a long-term relationship with clients. Come and work with me to find out that I am your excellent technology partner.Core Java
Apple TV ApplicationAndroid App DevelopmentiOS DevelopmentReact NativeiOSSwiftKotlinJava - $20 hourly
- 4.9/5
- (10 jobs)
Full stack developer with Java expertise. I am a full-stack developer (Backend expertise ) with more than around 7 years of experience in building web apps using Java, Spring boot, Hibernate, MongoDB, MySQL, ElasticSearch, Redis, Queues like Kafka/RabbitMQ. I have developed various enterprise microservices applications which were meant to be scalable and performance intensive. I'm fluent in English.I'm passionate about web technologies, therefore, whatever I do I try to deliver my best and try to learn new things every day. Please send me a message if you building something awesome. I can complete your project successfully with my skills and experience. Expert in the following areas: Backend: Java Angular Technologies and Frameworks: Spring Boot Spring AOP Blockchain(Crypto currency) JPA & Criteria API REST Services GCM(Google Cloud Messaging) Firebase Messaging Websockets Integration with external systems: Twitter, Google, Facebook, SendGrid. Application/Web Servers: Tomcat Cache: Redis. Messaging Systems: Apache Kafka, RabbitMQ. Event Streaming: Kafka Streaming. Databases: MySQL MongoDB ElasticSearch. Database Access: JDBC Spring(JDBCTemplate, HibernateTemplate, JpaTemplate) Spring Data Mybatis. Front-end programming: HTML CSS3 Javascript Angular 6 Websockets(STOMP) Bootstrap. Version control system: Git, SVN. Have experience with Agile and Scrum methodologies.Core Java
FirebaseMySQL ProgrammingCryptocurrencyElasticsearchAPI DevelopmentApache KafkaJavaRESTful ArchitectureSpring BootSpring FrameworkRedisJava Persistence APIAPI - $50 hourly
- 5.0/5
- (60 jobs)
I'm an experienced and professional mobile Android developer doing freelance, working remotely and looking for great projects to work on. I have 10+ years of experience in Mobile App Development using Java, Kotlin, Flutter, Firebase, AWS, Mongo Db, Room, User Authentication, and AI-driven applications. Summary of Qualifications • Expert understanding of core mobile technologies standards • Development of software, mobile web apps • Solid understanding of how the android OS works for the best performance • Have experience as Flutter Developer as well as replicating apps after iOS developer • Modern tooling and workflow • Ability to write high-performance, maintainable and reusable code • Appreciation for quality, usability, user experience (UX), accessibility and compatibility • 10+ years of experience • Highly motivated, self-starter, fast learner, hard worker, organized, attentive to details and a team player • Good communication skills. Fluent in English , both written and verbal • Sense of aesthetic and design • Always up-to-date with the latest technologies, techniques, optimizations and best practicesCore Java
Android AppAOSPCSSSQLFlutterGitAndroid SDKKotlinAndroid StudioSmartphoneMobile App DevelopmentAndroid App DevelopmentAndroidJavaFirebase - $50 hourly
- 5.0/5
- (120 jobs)
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.Core Java
Microsoft ExcelDocument Management SystemAPIAlgorithm DevelopmentData StructuresAPI DevelopmentHibernateObject-Oriented ProgrammingJava.NET FrameworkMySQLDesktop ApplicationC++ - $40 hourly
- 5.0/5
- (37 jobs)
Experienced Atlassian addon developer with proficiency in both Server (Java-based) and Cloud (React.js/Forge based) development, specializing in designing and developing addons that seamlessly integrate with Atlassian tools like Jira and Confluence. With over 7 years of experience in full-stack web development, and 5 years in the Atlassian ecosystem, I have developed a strong expertise in Java, Spring Boot, Hibernate, and modern JavaScript frameworks such as Next.js, Nest.js. I have built several addons in the Atlassian Marketplace that have helped my clients improve their productivity, enhance their workflows, and streamline their processes: ➡️ Votazz Apps [ marketplace.atlassian.com/vendors/1219338 ] ➡️ Raledo Apps [ marketplace.atlassian.com/vendors/1221179 ] ➡️ Advanced Table [ marketplace.atlassian.com/apps/1220950 ] ➡️ TimeCamp [ marketplace.atlassian.com/apps/1219229 ] ➡️ Mail page [ marketplace.atlassian.com/apps/1214285 ] ➡️ ContextQA [ marketplace.atlassian.com/apps/1229465 ] My deep understanding of Jira/Confluence REST APIs and SDKs for both Cloud and Server versions allows me to develop addons that meet the unique needs of each client. Whether it's building custom business workflows, designing custom forms and UIs, or developing integrations with other tools, I have the expertise to deliver high-quality solutions that exceed expectations. In addition, I can help you with the Atlassian Data Center submission and approval process, which is strictly rigorous: ✅Review your addon and ensure that it meets the Atlassian Data Center requirements ✅Help you create a Data Center app submission package, including required documentation and supporting materials ✅Advise you on best practices for app testing, including performance, stress, and scalability testing ✅Assist with configuring and testing your app in a Data Center environment ✅Help you identify and address any security vulnerabilities or performance issues in your app ✅Assist with filling out and submitting the Data Center app submission form ✅Provide ongoing support and assistance during the review and approval process ✅Help you address any feedback or issues raised during the review process Let’s get your next innovative addon product built and published into the Atlassian Marketplace 🚀Core Java
Atlassian CrowdServerless ComputingNext.jsReact NativeFront-End DevelopmentHTML5Amazon Web ServicesCSS 3Atlassian ConfluenceReact BootstrapAWS LambdaSoftware Architecture & DesignReactAmazon API Gateway - $35 hourly
- 4.7/5
- (132 jobs)
I offer premium service to my clients. Extensive success developing for both IOS and Android platforms for individual clients sets me apart from other professionals. I bring a wealth of experience and skills to the table. Key Highlights: Top Rated Expert: Recognized as a Top Rated Expert on Upwork, I am committed to delivering exceptional results. Outstanding Coding Skill: My coding skills are exceptional, ensuring a high level of quality in every project. Client Satisfaction: I take immense pride in ensuring 100% client satisfaction, reflecting my dedication to excellence. Pixel Perfect UI Design: My expertise in mobile app UI design ensures a pixel-perfect user interface. Experience: With over 9 years of experience, I have successfully launched more than 125 projects across various domains and technologies. Let's chat about how I can level up your business: My Skills 👉 React Native 👉 Swift 👉 Flutter 👉 Kotlin 👉 Java 👉 Node.js I am a Top rated Plus and Expert Vetted, I have maintained 100% customer satisfaction and repeat business by genuinely caring about my clients product , budget , and communication needs. I am passionate about mobile development, and that always comes across in the quality of work . Outside of development , I have 9 years of experience at the executive level in information Technology . This translates into strong business accumen and experience managing budgets , projects both locally and off-shore. Robust technology and business experience combine for a strong project outcomes no matters the size. I welcome discussing your projects and helping you find a success.I encourage you to check out my Upwork Profile. It will give you a good understanding of who I am and what I do.Core Java
Adobe DreamweaverjQueryJavaAdobe IllustratorAndroidHTML5Adobe PhotoshopAdobe InDesign - $25 hourly
- 4.5/5
- (105 jobs)
10+ Year Experience | 6000+ Hours work | 50+ Mobile Application | Individual Extensive success developing for the Flutter platform for individual clients as well as larger companies. Expert development for Android, iPhone, iPad using Flutter, Kotlin, and Swift. I have launched my apps into the store that have reached Top status, and I have worked with individuals (including many first-timers!) and larger companies on apps from MVP to those with user bases into the tens of millions. I have created and improved dozens of successful applications for clients in the areas of social networking, education, entertainment, self-help, fitness, lifestyle, and commerce. I have In-depth knowledge of industry practices and application development protocols. How can I help you: - Build an app from ideation to MVP and beyond - Revive, update or fix existing applications in need of care and feeding - Integrate new or existing applications into popular back-ends like Firebase | AWS | Azure - Get previously stalled app development efforts over the finish line - Consult on feature possibilities, App Store guidelines, and monetisation strategies - Perform code reviews, Write Unit, Bloc, UI or Integration test-case I am Top Rated Plus. I have maintained 100% customer satisfaction and repeat business by genuinely caring about my client's product, budget, and communication needs. I am passionate about mobile development, and that always comes across in the quality of my work, Updating knowledge and skills through continuous learning is the key. Expert Flutter Developer | Flutter Development | Mobile Full Stack Developer | Mobile DevelopmentCore Java
StripeWeb ApplicationCI/CD PlatformMobile App RedesignAndroid App DevelopmentMobile App DevelopmentIn-App PurchasesDartFlutterAndroidHybrid App DevelopmentNative App Development - $30 hourly
- 4.5/5
- (79 jobs)
I have 11 years of working experience in video streaming, web development, and mobile app development. I have developed several custom modules for video transcoding, live recording, chat, video conference, IP camera restream, IPTV channel restream, and several others. I like to give a demo or POC first and then start a real project; this makes the vision more clear to both parties (buyer and service provider). I completed my postgraduate degree in 2007, and after that, I started my professional career in Java Struts/Spring and Hibernate. After that, I started the core apps of Android in 2010 and then started XMPP-based chat apps for iOS. Video Streaming: I have been working with WOWZA, Red5, and FMS since 2009. I started using NODE JS, React JS, and Socket JS HTML5 with WebRTC because this technology is growing rapidly and modern browsers are also ready to support it. I have good experience with Fabric.JS for HTML5 canvas-based video editing and drawing tools. I believe success only requires hard work and an honest attempt.Core Java
Video ConversionAdobe FlashWowza Media ServerVideo StreamXMPPFFmpegRed5WordPressPHPiOS DevelopmentJavaWebRTCNode.js - $70 hourly
- 5.0/5
- (17 jobs)
I specialize in a development of high-quality iOS applications for more than 8 years. My #1 goal is to create superlative products, targeted to AppStore and to provide software development services which meet particular needs of my customers. I seek to create products in accordance with the most stringent quality standards stated by Apple. Listed below are my experience and skills: - Swift, Objective-c - Interaction with web and social services - Customizing UI conveniently and friendly - AR, ARKit, SceneKit - Core Location, MapKit, Google maps - Social Networking Applications - SQLite, Core Data, MongoDB - REST API, XML, JSON, Apollo GraphQL - InApp Purchases, Push Notifications - 3rd party libraries and frameworks - Github, Bitbucket - Firebase Please feel free to contact me if you need my help!Core Java
Apple XcodeMobile App DevelopmentiOS DevelopmentSwiftObjective-CLocation-Based ServiceUser AuthenticationIn-App PurchasesChat & Messaging SoftwareiOSAPI Integration - $40 hourly
- 5.0/5
- (46 jobs)
Are you looking for a rockstar developer? Look no further. If you value top quality, clean code, and efficient workflow, you just found the right guy! Our collaboration will be based on excellent communication, great attention to detail, solid development experience, and an excessive dedication to bringing more value to your product! Services: - React Native / React.js / Redux; - Flutter, FlutterFlow, Dart; - Native iOS mobile development (iPhone / iPad) using XCode and Swift/Objective-C; - Native Android mobile development using Android Studio/Eclipse and Java; - PHP-based websites (Laravel framework), Javascript, HTML5, CSS3, AJAX; - RESTful APIs implementation, integration with social media APIs (Facebook, Twitter, YouTube); - Databases (MySQL, PostgreSQL, SQLite); - Source code versioning (Git - GitHub/BitBucket, SVN); - Porting from iOS to Android and the other way around.Core Java
Web Services DevelopmentiPad App DevelopmentAndroid SDKLaraveliOSJavaScriptReact NativeJavaAndroidReactPHPObjective-CiOS DevelopmentAndroid App Development - $25 hourly
- 4.5/5
- (80 jobs)
I am an experienced IT professional having more than 14 years of experience in web development using java, java EE, PHP, javascript, html, react, node etc I also have proficiency in other tools like eclipse, git, jira, redmine, VS Code, MS Office etc I am open to work on various assignments on web development, android development, Wordpress, data scraping, java development, data entry, Excel VB etc. I am also available for any tutoring related to java, web technologies etc I also have a good hands on design softwares like photoshop, corel draw, illustrator. So I am ready to work on any design related work like website, logo, business cards, invitation cards, bags,t-shirts and any branding related activities. I can also work in soccial media marketing, digital marketing, SEO etc I am ready to take up different transcription, translation, content writing activties as well.Core Java
React NativeTcl/TkNode.jsSpring BootCSS 3ReactSQLJavaJavaScriptjQueryPHPRESTful Architecture - $30 hourly
- 4.9/5
- (33 jobs)
🌟 Crafting Exceptional Solutions for Business and Real-World Challenges 👋Hello! I'm Rohit, an AWS certified developer with over 10 years of hands-on experience as a Full Stack Developer and Solution Architect. I specialize in creating robust, scalable software solutions that blend innovative thinking with practical expertise. Armed with a Master's degree in Information Security, I excel in delivering high-quality technical solutions and tackling complex challenges. Key Skills Highlights: 🔹 Architectural Vision: Translating corporate needs into forward-thinking designs aligned with current and future goals. 🔹 Technology Mastery: Proficient in diverse programming languages and modern technologies, ensuring a balance of functionality, performance, and maintainability. 🔹 Cloud and DevOps Expertise: Deep expertise in AWS, Azure, and Google Cloud, optimizing development processes for efficient and scalable solutions. 🔹 Client Collaboration: Working closely with clients to ensure technical designs meet business objectives seamlessly. Technical Skills: 🚀 Programming Languages: Mastery in C, C++, Python, Django, and C#. Extensive experience in frontend technologies like ReactJS, HTML5, CSS3, and JavaScript. 🚀 System and Database Design: Expertise in designing scalable systems and optimizing databases. 🚀 API Design: Skilled in crafting robust RESTful APIs. 🚀 Cloud Computing: Proficient in designing and implementing cloud-based solutions. 🚀 Containerization and Orchestration: Proficient in Docker and Kubernetes. 🚀 Security: Knowledgeable in software security principles and secure coding practices, with a focus on EU-GDPR compliance and AWS security services. 🚀 AI and ML: Skilled in implementing AI and ML models using frameworks like TensorFlow and scikit-learn. 🚀 DevOps Practices: Specialized in cost-optimized DevOps infrastructure with extensive AWS experience, including EC2, Elastic Beanstalk, RDS, DynamoDB, Lambda, and CI/CD pipelines. 🚀 Performance Optimization: Enhancing software performance through code profiling and system tuning. 🌟EXTRA PROFICIENCY: I) Analytical Tools Integration: Hands-on experience with Google Analytics, Microsoft Clarity, Visitor Analytics, Hotjar, and Hubspot for actionable insights and enhanced user engagement. II) Testing & QA: Proficient in SonarQube for code quality analysis, automated testing with Selenium, load testing with JMeter, and robust penetration testing. Proven Track Record: My portfolio features successful collaborations with startups and enterprises, earning high acclaim and recommendations. I am committed to delivering excellence in every project, transforming ideas into remarkable web solutions. Let's collaborate on your next project and create digital experiences that stand out. Reach out to me today! Warm Regards, Rohit #Webdevelopmentexpert #FrontEndDeveloper #BackEndDeveloper #WebDesignGuru #CodeIgniterPro #LaravelWizard #WordPressMaster #ShopifyExpert #MagentoMaestro #WebflowSavvy #UIUXWhiz #BootstrapNinja #JavaScriptGuru #ReactRockstar #NodejsEnthusiast #PHPWizard #DigitalSolutionist #TechInnovator #QualityFirst #TimelyDelivery #ClientSatisfaction #WebDevSolutions #CreativeCoder #ProblemSolver #ExperiencedDev #StartupPartner #WebSolutions #InnovativeDesignsCore Java
HubSpotAWS CloudFormationCI/CDGoogle AnalyticsDevOpsAWS LambdaBootstrapCSSHTML5TensorFlowNumPypandasMySQLDjangoPython - $25 hourly
- 5.0/5
- (126 jobs)
My name is Gökhan Yörük and I'm a 25-year-old software developer who is striving to become a Full Stack Developer. I'm proficient in Python, HTML, CSS, JavaScript, C#, and Java. I prefer to work in a solution-focused manner and always strive to do my best to solve problems. I'm motivated to continually improve myself and am open to learning new things.Core Java
Data ScrapingGoogle Chrome ExtensionPythonWeb CrawlingWeb ScrapingCSS 3BootstrapJavaScriptJavaHTML5Selenium - $50 hourly
- 4.7/5
- (95 jobs)
Hello there!👋 I am a back-end software developer with over 4 years of experience in the software industry. I have experience in the following areas: - Back-end software development - API design and integration - CI/CD - Agile software development - UML diagramming (sequence, state, use case diagrams, you name it.) - Programming tutoring Some of the tools and technologies I specialize in include the following: - Microsoft Azure - .NET 6 - 8, ADO.NET, Signal R, Web APIs, Entity Framework Core - Java, JDBC, Hibernate, Spring Boot - SingleStore DB, MySQL, MongoDB - JavaScript, TypeScript - Object-oriented designCore Java
GitTypeScript.NET CoreAzure DevOpsSpring BootObject-Oriented ProgrammingMicrosoft AzureUnified Modeling LanguageJavaC#JavaScriptSQLSpring FrameworkTeaching Programming - $40 hourly
- 4.2/5
- (37 jobs)
Hi And welcome to my profile, I have over 4 years of experience with Android development and over 2 years of experience with Flutter development I was born to be a computer software engineer and then in the age of 14 I jumped into the programming. later I completed my Software Engineering degree and became an Android Developer. I chose Android because I like working on operation systems and open for new challenges. I have developed native applications similar to Uber and WhatsApp why should you hire me? Here are the advantages to hire me: ● Responsible for my role in work. ● Available 30~50 hrs/week, on any time zone ● Top quality with top speed ● Accurate and keen eyes for pixel perfect UI/UX design, as well as bug free coding skill ● Good communication with professional English ● For the biggest advantage, I'm younger yet and have a big potentiality to become familiar with any new aspects or fields. My passion is actually to explore new fields and to investigate new technology. I have been already an expert in Android, but have much more abilities. I'm open to any kind of discussion on your project. Please feel free to touch me. Hope to work together for an amazing product. lessCore Java
Web DevelopmentCodeIgniterLaravelMobile App DevelopmentAndroid App DevelopmentChat & Messaging SoftwareSmartphoneFlutterPHPJavaAngularJSAndroid - $25 hourly
- 4.8/5
- (71 jobs)
Hi, I am from Galle, Sri Lanka , an expert Java developer. I have 21+ years of experience working wit Java and web developments. I have specialized expertise in Service Oriented Architecture (SOA) and Sound with micro-service architecture. In my Upwork career, I have implemented several successful projects with web services. Also, i have done successful B2B integrations via different APIs like REST/SOAP/XML. Also, I have good knowledge and experience working Java, Multi-Threading, Concurrency...etc.I am sound with the Spring framework (Spring boot, Spring MVC + Thymeleaf, Spring Security, Spring Data JPA...etc), J2EE (Jakarta EE) , JMS , JPA, Hibernate, JFX ...etc. For more details, please visit my profile. I have a top-rated Upwork profile. Also, I have strong database knowledge and have worked with MySql , MSSQL, Postgres, Oracle...etc. I am sound with PHP, Pearl, Bash, Python, Lua, Javascript like scripting languages. Also, I have good experience with handling Windows/Linux operating systems.Core Java
Linux System AdministrationWeb ServiceOracle GlassFish ServerWSO2ASP.NET MVCPHPPythonAPIC#JavaAmazon Web ServicesRESTful APISpring BootAWS LambdaAPI Development - $35 hourly
- 5.0/5
- (19 jobs)
Greetings, I proudly serve as the CTO at Intelliceed, a distinguished company with a relentless focus on Web App development. Our expertise spans diverse sectors, including: ✅ FINTECH ✅ HEALTHCARE ✅ SOCIAL NETWORKS AND MARKETPLACES ✅ E-LEARNING/LMS ✅ DOCUMENT MANAGEMENT SOFTWARE Our mission is nothing short of transformational: we are dedicated to making people's lives more convenient and efficient. Since our inception in 2017, Intelliceed has been at the forefront of improving the quality of life, having successfully delivered over 20 bespoke projects. Our team comprises exceptional talent, including React.js virtuosos, Java experts, DevOps maestros, Project Managers, and QA engineers. Our Impressive Technology Stack: 🔹 Back-End ✔ Java, Spring, Next.js ✔ Kafka, Jenkins, Docker, Kubernetes ✔ Hibernate, Redis, RabbitMQ ✔ AWS (SQS, DynamoDB, SNS), Azure, GCP ✔ MySQL, PostgreSQL, Elastic Search 🔹 Front-End ✔ JavaScript, React, React Native, Next.js, Angular ✔ HTML, CSS 📌 Our primary mission is to empower STARTUPS, BUSINESS OWNERS & FOUNDERS, and DIGITAL AGENCIES by supplementing their teams with seasoned engineers and developers. We are poised and ready to assist you with a wide range of services, including: 🔸 Web Application Development 🔸 Consulting and Business Analysis 🔸 Hybrid Applications Development 🔸 DevOps implementation with AWS, Azure, GCP cloud providers 🔸 Database Application Development 🔸 Manual and Automatic QA Our Engagement Models 🔥 Dedicated Team – Your extended, fully managed development team 🔥 Project Outsourcing – End-to-end project development 🔥 Outstaffing – Directly hiring skilled engineers 🔥 Team Recruitment – Assembling a team tailored to your project How It Works: 🔹 Introduction – We begin by understanding your request. 🔹 Talent Matching – Our team selects the right talent or team for your needs. 🔹 In-Depth Research – We analyze your request and define tailored collaboration terms. 🔹 Proposal & Negotiation – Intelliceed presents a customized proposal and refines it with you. 🔹 Contract Signing – We formalize the agreement. 🔹 Collaboration Begins – We launch our partnership and start working together. You can initiate a free consultation regarding your project to witness how we can synergize effectively. Send me an invite, and together, we'll embark on the journey of building remarkable projects that leave an indelible impact! Let's turn your vision into a reality. 🚀 🔥🔥🔥What Our Clients Say About Their Experience Working With Us ⭐⭐⭐⭐⭐ The guys are creative, proactive, and not afraid of difficulties. ⭐⭐⭐⭐⭐ We’re very impressed with the work that the team did. ⭐⭐⭐⭐⭐ We couldn't be happier and never experienced any performance or management issues with the IntelliCeed team. Everything we planned was correctly estimated and met all the milestones. ⭐⭐⭐⭐⭐ I broadly gave them instructions on what I wanted and they were able to produce it for me. ⭐⭐⭐⭐⭐ They're focused on delivering value. 𝐒𝐤𝐢𝐥𝐥𝐬 𝐢𝐧 𝐉𝐚𝐯𝐚 & 𝐄𝐧𝐭𝐞𝐫𝐩𝐫𝐢𝐬𝐞 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭: 🔸 Java, Java EE (Servlets, JSP, JSTL) | Java Core, OOP, Collections & Stream API 🔸 Spring Framework (Spring Boot, MVC, Security, Data JPA) | Hibernate, JPA 🔸 RESTful API Design | OpenAPI | Swagger | Cucumber 🔸 Databases: PostgreSQL, MySQL, Oracle, MSSQL, MongoDB, DynamoDB 🔸 Frontend: JSF, PrimeFaces, jQuery, GWT, AngularJS, HTML/CSS/JS 🔸 Message Queues: RabbitMQ, ActiveMQ | Cronjobs & Event Handling 🔸 Servers: Tomcat, JBoss, WebSphere, WebLogic, Jetty, Apache, Nginx 🔸 DevOps & Tools: Docker, Jenkins, GitHub Actions, Git (GitHub, GitLab, Bitbucket), SVN, Maven, Ant, Liquibase 𝐒𝐨𝐟𝐭𝐰𝐚𝐫𝐞 𝐄𝐧𝐠𝐢𝐧𝐞𝐞𝐫𝐢𝐧𝐠 & 𝐀𝐫𝐜𝐡𝐢𝐭𝐞𝐜𝐭𝐮𝐫𝐞: 🔹 Strong command of Object-Oriented Programming & Design Patterns 🔹 J2EE Design Patterns, MVC Architecture, Facade/Service Layers 🔹 Data & Product Modeling | Import/Export Pipelines | Integration Layer 🔹 Test-Driven Development (TDD): JUnit, Mockito, AssertJ, Hamcrest 🔹 Cloud Platforms & Services: AWS (S3, SNS, SQS, DynamoDB) 🔹 API & Payment Gateway Integrations (Stripe, PayPal, Braintree, etc.) 🔹 Agile Methodologies: Scrum, Kanban | CI/CD with Jenkins, GitLab 🔹 Extensive experience in FinTech, Healthcare, Real Estate, and HR Systems 𝐇𝐢𝐠𝐡𝐥𝐢𝐠𝐡𝐭𝐞𝐝 𝐒𝐤𝐢𝐥𝐥𝐬: Java EE Development, Enterprise Architecture (J2EE, MVC), Spring Framework (Boot, Security, Data JPA), RESTful API Development, Front-End Integration (JSF, PrimeFaces, jQuery, AngularJS), Microservices & Messaging (RabbitMQ, ActiveMQ), Containerization (Docker), Database Design (PostgreSQL, Oracle, MongoDB), Payment Systems Integration, Cloud Technologies (AWS: S3, SQS, SNS, DynamoDB), Testing & QA Automation (JUnit, Mockito, Cucumber), DevOps Practices (CI/CD with Jenkins, GitHub Actions, Maven), Agile Project Management, Version Control (Git, GitHub, GitLab), Cross-domain Experience (FinTech, Healthcare, Real Estate, HR Tech) Last updated: April 2025Core Java
Full-Stack DevelopmentFront-End DevelopmentBack-End DevelopmentSpring BootScalaReactSpring SecuritySQLSpring FrameworkAngularJSGoogle Web ToolkitHibernateJavaMongoDB - $35 hourly
- 4.8/5
- (97 jobs)
I am a Los Angeles-based Professional with 17+ years of work experience where I took roles of Full Stack Developer, Project Manager, Solutions Architect, Team Lead, DevOps Engineer, Project Consultant, Cloud Consultant, Cloud Architect, etc. I have a rich portfolio of Web and Mobile Apps(both iOS and Android). ***************** I have led Projects for well-known companies like Sony Pictures, Paramount Pictures, 20th Century Fox, Prince Cruise Line(PCL), Masimo, and Creative Artist Agency. ***************** As a Full Stack Developer/Team Lead/Project Manager/Solutions Architect I have extensive experience with a Web application, Mobile Applications, Desktop Application Development, UI/UX Design, Tech Support, Cloud Architect, and Consulting Projects involving technologies like Wordpress, PHP, Java, Python, C#, Javascript, React, Angular, Node.js, Express.js, Shopify, Swift, Objective-C, React Native, AWS, GCP, Microsoft Azure, etc. - Build and develop the project team to ensure maximum performance, providing purpose, direction, and motivation. - Lead projects from requirements definition through deployment, identifying schedules, scopes, budget estimations, and project implementation plans, including risk mitigation. - To coordinate internal and external resources, ensuring projects remain within scope, schedule, and defined budgets, in collaboration with project staff from various functional departments. - Analyze project progress and, when necessary, adapt scope, timelines, and costs to ensure that the project team adheres to project requirements. - Establish and maintain relationships with appropriate client stakeholders, providing day-to-day contact on project status and changes As DevOps/Cloud Engineer I have extensive experience in designing, implementing, and maintaining complex Cloud-based infrastructure with a focus on security, scalability, and high availability. AWS Services: Deployment Automation: Proficient in automating deployment processes using AWS CloudFormation, Terraform, and Ansible to reduce errors and improve speed. Continuous Integration and Delivery: Skilled in setting up CI/CD pipelines using AWS CodePipeline, AWS CodeBuild, and Jenkins for automated build, test, and deployment processes. Monitoring and Alerting: Capable of setting up monitoring systems using AWS CloudWatch, Prometheus, and Grafana to identify performance issues proactively. Security and Compliance: Knowledgeable in implementing security best practices and automated compliance checks using AWS Config and AWS Security Hub. Cost Optimization: Experienced in optimizing AWS spending using tools like AWS Cost Explorer, AWS Budgets, reserved instances, spot instances, and auto-scaling. Microsoft Azure Services: DevOps Strategies: Proficient in designing and implementing effective DevOps strategies using Microsoft Azure for continuous integration, delivery, and deployment. Infrastructure Provisioning and Configuration: Experienced in provisioning and configuring Azure infrastructure using tools like Azure Resource Manager (ARM) templates and Terraform. Continuous Integration and Continuous Deployment (CI/CD): Skilled in establishing CI/CD pipelines using Azure DevOps for automated build, test, and deployment processes. Automation and Orchestration: Capable of automating tasks and processes using PowerShell, Azure CLI, Azure Automation, and Azure Logic Apps to streamline operations. GCP Services: Deployment Automation: Proficient in automating deployment processes using tools like Google Cloud Deployment Manager and Terraform to ensure consistency and reliability. Continuous Integration and Delivery: Skilled in setting up CI/CD pipelines using Cloud Build and Jenkins on GCP for automated testing, building, and deployment of applications. Monitoring and Alerting: Capable of implementing monitoring and alerting systems using Stackdriver Monitoring and Stackdriver Logging to identify and resolve issues promptly. Security and Compliance: Knowledgeable in implementing security controls and compliance standards using GCP Identity and Access Management (IAM) and Security Command Center. Cost Optimization: Experienced in optimizing costs on GCP using tools like Cost Explorer and Budgets, as well as utilizing features like sustained use discounts and preemptible VMs to minimize expenses. *****************Core Java
Node.jsAmazon Web ServicesShopifyMobile App DevelopmentAngularJavaWeb ApplicationPythonAndroid App DevelopmentPHPBigQueryiOS DevelopmentMicrosoft SQL SSASAmazon RedshiftMicrosoft Azure - $30 hourly
- 5.0/5
- (9 jobs)
Passionate programmer, ever hungry to learn and earn. I have a CAN DO attitude and i am a dedicated learner. EXPERIENCE : 9 Years Backend Skills : * Java * Grails * Node * Groovy * Spring * Hibernate * AWS Frontend Skills : * Javascript * React * Redux * AngularJs * HighCharts * Html * Sass, Less Databases : * Mysql * Mongo * Elastic Search * SnowflakeCore Java
Agile Software DevelopmentElasticsearchRESTful APISoftware Architecture & DesignWeb DevelopmentReactAngularJSGrailsJavaScriptJavaHTML5MongoDBSpring FrameworkAJAX - $90 hourly
- 5.0/5
- (9 jobs)
I am a java developer with more than 10 years of experience for whom key moments in work are high quality and punctuality. I'll try to help you implement your ideas in life and make your project successful! Very quick studying of new technologies, methods and approaches as well as excellent understanding of java-core and OOP principles have always been my strong suit. Key technologies which I use: J2EE, J2SE, JDBI , JPA (hibernate), liquibase, EJB, REST (dropwizard framework), JaxWS, GWT, angular to name but a few. I would be glad to learn new technologies which are used in your projects. Databases: MySql, PostgreSQL, Oracle, Mongo IDE: IntelliJ IDEA mainly, Eclipse Build: Maven, Ant, Hudson, Jenkins, BambooCore Java
Jakarta Server PagesSQLJ2EEMultithreaded ProgrammingJ2SEAngularJSJava Servlet APIJavaPostgreSQL - $30 hourly
- 3.8/5
- (109 jobs)
⭐️⭐️⭐️⭐️⭐️ In TOP 3 % Talent On Upwork 🏆 Certified Mobile App Developer | Flutter | React Native| Kotlin | Full Stack Developer ✅ 250 ➕ Mobile apps 100 ➕ websites live ✅ 80%+ Long-term & Repeat Clients ✅Senior Full Stack Developer with 13+ years of experience 🔝 𝐓𝐨𝐩 𝐑𝐚𝐭𝐞𝐝 𝐏𝐥𝐮𝐬 𝐝𝐞𝐯𝐞𝐥𝐨𝐩𝐞𝐫 🔸My availability is according to your country's time zone 🔸High-Quality Work🔸 Cost-Effective I am very efficient in my work. My first and foremost goal is to satisfy my clients From start to finish till the project is delivered, I constantly communicate with my clients and support them in their time zone. I update the client daily. The most important thing is to provide maintenance support to the client after the completion of any project. Whether you are a 𝗦𝘁𝗮𝗿𝘁𝘂𝗽, Newley 𝗕𝘂𝘀𝗶𝗻𝗲𝘀𝘀 or looking for 𝗠𝗩𝗣, I will give you Best 𝗤𝘂𝗮𝗹𝗶𝘁𝘆 𝗦𝗲𝗿𝘃𝗶𝗰𝗲𝘀 at an 𝗔𝗳𝗳𝗼𝗿𝗱𝗮𝗯𝗹𝗲 𝗖𝗼𝘀𝘁, 💯 𝗙𝗿𝗲𝗲 𝟯𝟬 𝗱𝗮𝘆𝘀 𝘀𝘂𝗽𝗽𝗼𝗿𝘁 𝗮𝗳𝘁𝗲𝗿 𝗽𝗿𝗼𝗷𝗲𝗰𝘁 𝗰𝗼𝗺𝗽𝗹𝗲𝘁𝗶𝗼𝗻 𝐖𝐡𝐚𝐭 𝐂𝐥𝐢𝐞𝐧𝐭 𝐬𝐚𝐲𝐬 𝐚𝐛𝐨𝐮𝐭 𝐦𝐞🙂 ⭐⭐⭐⭐⭐5.00 "Rajat and the team were great to work with! They are skilled, great communicators, and good people. They worked hard to accomplish whatever task I had for them. I highly recommend them and will be using them in the future for other projects!" 𝑹𝒊𝒄𝒉 𝑴𝒊𝒍𝒍𝒆𝒓-𝑷𝒂𝒚𝒔𝒐𝒏 ⭐⭐⭐⭐⭐ 5.00 "Amazing work as always! I highly recommend working with Appentus team." 𝑻𝒐𝒃𝒊𝒂𝒔 𝗘𝘅𝗽𝗲𝗿𝘁 𝗶𝗻 𝗛𝘆𝗯𝗿𝗶𝗱 𝗔𝗽𝗽𝘀 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 / 𝐍𝐚𝐭𝐢𝐯𝐞𝗔𝗽𝗽 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 ► React Native ► Flutter ► Android (Java Native App Development) ► IOS (Swift App Development) ► Firebase ► MVC/MVP/MVVM ► REST APIs ► In-App Purchases 𝐈𝐧𝐝𝐮𝐬𝐭𝐫𝐢𝐞𝐬 𝐄𝐱𝐩𝐞𝐫𝐢𝐞𝐧𝐜𝐞: 🟥Finance 🟥Healthcare. 🟥E-commerce 🟥Logistics and Transportation 🟥Education 🟥Public safety. 🟥 Banking 🟥 Automotive 🟥 B2B 🟥 B2C 𝗣𝗿𝗼𝗳𝗶𝗰𝗶𝗲𝗻𝗰𝘆 𝗰𝗼𝗺𝗽𝗿𝗲𝗵𝗲𝗻𝘀𝗶𝘃𝗲 𝘀𝗸𝗶𝗹𝗹𝘀 𝗶𝗻 𝘁𝗵𝗲 𝗳𝗼𝗹𝗹𝗼𝘄𝗶𝗻𝗴 𝘁𝗲𝗰𝗵𝗻𝗼𝗹𝗼𝗴𝗶𝗲𝘀: ✔OpenAI and ChatGPT API (gpt-4, whisper) and various other models. ✔Authorization with Google, Facebook, Twitter, Auth0, Github, Gmail and others ✔WordPress API - Uploading images and templates via WordPress API ✔ Full Stack Development: MEAN | MERN ✔ PHP Frameworks (laravel, codeigniter, yii, cakephp and zend). ✔ PHP CMS (Wordpress, Shopify). ✔ Database integration: SQLite, firebase, etc. ✔ API integration ✔ Frontend Development: HTML5, CSS3, Bootstrap v5.3, JavaScript, TypeScript, React.js, Vue.js, Angular ✔ Backend Development: Laravel, PHP, Node.js, Express.js, Django, Flask ✔Database Management: MongoDB, MySQL, PostgreSQL, Firebase, SQLite ✔API Development and Integration: RESTful APIs, GraphQL, OAuth, JWT ✔Cloud Services: AWS, Microsoft, Firebase, Azure Google Cloud Platform (GCP), Version Control: Git, GitHub, Bitbucket 𝗪𝗵𝘆 𝗖𝗵𝗼𝗼𝘀𝗲 𝗠𝗲: ✔ Proven track record of delivering high-quality projects on time and within budget. ✔ Strong communication skills, ensuring clear understanding and alignment with client requirements. Feel free to reach out to discuss your project requirements and explore how we can work together. Looking forward to connecting! 🙂Core Java
FlutteriOS DevelopmentGameAndroid App DevelopmentSwiftDjangoHealthKitNode.jsMobile App DevelopmentJavaPHPKotlinPythonAndroidSmart Contract Want to browse more freelancers?
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At A Glance: Core Java
Developing and programming software is the backbone of many modern businesses and industries. Programs and applications can be created to fill many different roles, including games, e-commerce, and interactive web content. These applications can be used internally for tracking and managing other digital resources, or developed as standalone software to distribute to customers and consumers. One important feature of any program is that it is written and developed in a programming language that allows it to be easily ported and executed on other computer systems. Core Java, commonly known as Java Standard Edition (SE), is one such programming language that gives you the portability and flexibility in your developed software that you need for your business and project. Taking advantage of an experienced Java developer or programmer is the most effective way to leverage this powerful language.
Java developers and programmers available on Upwork generally possess a deep knowledge and skill set. Backgrounds include building, writing, and developing programs from the ground up for a wide variety of uses. Java developers and programmers also have experience working with existing applications by adding additional functions or features. Core Java developers and programmers are highly computer-literate professionals with advanced mathematical skills and frequent experience working with other computer programming languages and development frameworks. The portable nature of applications written in Core Java lead to programmers’ and developers’ comfort with many different systems, which fills dynamic roles within a business or project.