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Rating is 4.8 out of 5.
4.8/5
based on 307 client reviews
  2. Development & IT Talent
  3. Back-End Developers
  4. (Current) Core Java Developers
  • $44 hourly

    • 4.8/5
    • (10 jobs)
    Skilled Mobile Engineer with more than 5 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 API
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Google Maps API
    Object-Oriented Programming
    XML
    Android SDK
    JSON
    SQLite Programming
    Material Design
    Mobile App Development
    iOS Development
    Firebase
    Android App Development
    Dart
    Flutter
    Android
  • $25 hourly

    • 4.8/5
    • (156 jobs)
    Over 20 years of experience in planning, developing and implementing various information technology and CRM solutions across Institutions.  Salesforce Certified Administrator. •Over 5 years of implementing customized CRM solutions to various clients like Verizon, Allianz Re-Insurance . •Automated Service, Sales and marketing processes using Salesforce Lightning flows and APEX/Visualforce • Implemented core Salesforce modules like Sales, Service, Financial, Health cloud for small businesses using Agile/Scrum methodologies • Integrated Salesforce with apps like Zoom, RingCentral, Box, Gmail using Zapier • Utilized Webservices/REST API to integrate Salesforce with third party applications. • Implemented Web to Lead, Web to Case and Email to Case channels. • Created OMNI Channel and Web Chat for customer service. • Built reports and dashboards to measure kpis. • Imported data into Salesforce using tools like DataLoader and workbench. • Implemented and created the full life cycle process for large-scale software development • Identified architectural improvements resulting in increased product reliability and responsiveness to new feature requests • Utilizing strong functional knowledge to drive product design • MS (Computer Science) , University of South Carolina, Columbia  Salesforce Certified Administrator  Sun Certified Programmer for Java 2 Platform  Sun Certified Web Component Developer for Java 2 Platform  Sun Certified Business Component Developer for Java 2 Platform  Project management for IT Profession TECHNICAL SKILLS • Java, J2EE, Java Servlets, JSP, JNDI, JFCs, EJB’s, Java Script, AJAX, Web services • Spring Webflow 2.5, STRUTS, Google Web Tool Kit, XML, XSL, ASP, .NET, Shell Scripts, JUnit • WebSphere 8.5, Tomcat, Web Logic 6.0, IIS, Silver Stream App Server, JRun, JWS • RAD 7.5, Eclipse, Visual Studio, JDeveloper, CVS, Clear Case, Stash, UML, Rational Rose • Oracle 11g, D2000, IBM DB2, MYSQL, MS SQL SERVER, MS ACCESS, Toad • Windows XP, IBM AIX and Unix (SUN SOLARIS 5.7), Silver Stream e-portal 2.2 • JIRA, Confluence, Cloud Services (PaaS), SalesForce Administration, APEX, Visualforce
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Salesforce Lightning
    XSL
    IBM DB2 Programming
    Oracle Database
    Spring Framework
    Apache Struts
    J2EE
    XML
    Jakarta Server Pages
  • $45 hourly

    • 5.0/5
    • (60 jobs)
    I'm an experienced and professional mobile and software developer doing freelance, working remotely (telecommute) and looking for great projects to work on. I love to make your ideas alive. I care about every single line of my code. 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 • Passionate about all aspects of development • Modern tooling and workflow • Ability to write high-performance, maintainable and reusable code • Appreciation for quality, usability, user experience (UX), accessibility and compatibility • 5+ 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 practices Hire me!
    vsuc_fltilesrefresh_TrophyIcon Core Java
    In-App Purchases
    Social Media Account Integration
    Camera
    Firebase
    Mobile Programming
    Mobile App Development
    Java
    Android App Development
    Android
  • $20 hourly

    • 4.9/5
    • (19 jobs)
    Over the last 15+ years, I have developed several Web Applications and mobile apps in android and iOS myself as well as managed teams to deliver clients in a satisfactory and timely manner. I am specialist in building applications from ground up. Most of my accomplished projects resulted in long-term association with my clients as I keep on adding values to the project from the concept phase to the final deployment to the stores and afterward. I look forward to building something beautiful and long-term with you. My skill sets in particular: 1. Web Application Development: Full Stack Development including both front end and backend a. Backend: PHP (Laravel, Codeigniter), Node.js, Express.js b. Frontend: Vue.js, Nuxt.js, Bootstrap, Tailwind CSS, Bulma CSS framework Especially proficient in rapid prototype development using some of the most prominent Vue based themes like Vuexy and Vuero. 2. Mobile Application Development: a. Hybrid / Cross platform apps: Flutter b. Native Apps: Objective C and Swift for iOS apps and Core Java and Kotlin for Android apps 3. Database: Scope understanding, Schema design, DB optimization a. MySQL b. Mongodb c. PostgreSQL d. AWS Aurora MySQL 4. API / WEB SERVICES Implementation 5. Server Setup and Deployment: Specialized in AWS environment a. Nginx b. Apache 6. Other Skills: - Scoping and Wireframing - Project Architecture Development and Project Management - Git for version control, AWS barebone server setup - Capability of solving complex logical problems in elegant manner - Extensive Experience in handling wellness apps besides social and service based hyper-local apps - Extensive Experience in custom CRM development, safety and health compliance based solutions, Do you have any questions? We can have a chat or call via Upwork messenger. Feel free to contact me!
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Vue.js
    Android
    Core Bluetooth
    Flutter
    Objective-C
    Swift
    iOS
    PHP
  • $25 hourly

    • 5.0/5
    • (52 jobs)
    - B.tech and M.tech in Computer Science - Worked as a Software engineer in Virtusa Corp & DIGIDEZ - More than 6 years of teaching experience - Oracle Certified Trainer - Helped students placed in FAANG Work Experience on Upwork 1. Wordpress Help "Aniket helped me with some issues on my WordPress project. He identified the issues and provided knowledgeable guidance to get my project on the right path." 2. Automation Project Phil Charles : "Another great session & good progress has been made on my automation project" 3. Technical Support "Aniket has a great work ethic, ensures he has clarity on what is expected, & executes. Great communication & technical skills with regards to my automation project." Thanks!
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Tutoring
    Web Design
    Computer Science
    Python
    Java
    CSS
    JavaScript
    Angular
    HTML
  • $18 hourly

    • 5.0/5
    • (4 jobs)
    I'm a Java developer with 3 years of experience in Enterprise projects. Strong technical skills, capable in developing large multifunctional software and features. High level of responsibility, always in contact with the client to achieve established goals. I have good problem solving skills and have a habit of covering my code with tests. Glad to provide modern programming patterns and edge technical solutions (if needed) and bring additional value to Client's business. Feel free to contact with any questions.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    JDBC
    JUnit
    Spring Security
    Hibernate
    Spring MVC
    Java Collections Framework
    Mockito
    Spring Boot
    PostgreSQL
    JavaFX
    Spring Framework
    Git
    JavaScript
    Java
  • $55 hourly

    • 4.3/5
    • (61 jobs)
    My name is Aman, and I am from North India. I have a master's degree in the computer science domain.I have over 15 years of IT experience, including 7 years as a Senior Technical Architect in handling team onsite and offshore projects In my previous companies, I effectively led cross-functional teams as a technical project manager to complete challenging projects on schedule and on budget. I've demonstrated my ability to successfully manage project scope, resources, and timeframes in order to assure project success. I can effectively communicate with both technical and non-technical stakeholders, such as developers, designers, and executives, thanks to my experience in both the technical and commercial worlds. I implemented Agile approaches in my former organization to improve project management procedures, which led to more productivity and improved project outcomes. Creating project plans, including budgets, timetables, and resource allocation, is another skill I have. I am proficient with the use of project management applications like Jira and Asana, and I am well-versed in the software development life cycle. Here, I am mentioning those projects that I have handled as a COO/CTO/Software Architecture and Full Stack developer. 1. Text Grid, (USA) - SAAS application My Role:- Software Architecture/CTO/COO 2. TankSpotter | Digital Software Services| (USA) - SAAS My Role:- Software Architecture/CTO/COO 3. CBO-Parts, (Monaco)- E-commerce Marketplace My Role: Software Architecture/Virtual CTO/Lead Technical Head 4. Shivalik Bank - Financial application My Role:- Software Architecture/CTO 5. Clone of Uber eats/Zomato (USA) My Role: Fractional CTO 6. Smart solution for property maintenance My Role: Software Architecture/CTO My responsibilities included, ================ 1. Managing Multiple Clients and Finalizing the Scope for proposed programs. 2. Launching Digital & Software Products to a Success. 3. Contributing to the successful growth of the Company's Programs. I am online most of the time, so I can quickly communicate with you. All people with whom I work have a very positive opinion about me and my job. I am looking forward to hearing from you. Best wishes,
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Fortune 500 Company
    Chief Architect
    Machine Learning
    Software Architecture & Design
    Technical Project Management
    Ruby on Rails
    Data Science
    Database Design
    Spring Boot
    Full-Stack Development
    DevOps
    PHP
    Software Development
    SaaS
    Mobile Apps
  • $20 hourly

    • 5.0/5
    • (7 jobs)
    Hi, thanks for reaching out to my profile on Upwork! I am enthusiastic and dedicated Software Engineer with 1 year of practice in Java Development. I have strong knowledge in Software Development Life Cycle, Algorithms, OOP and OOD principles, and design patterns. My expertise is Backend development. I'm a team player and a proactive person. Here's what my main area of expertise looks like: ✅Java Development: Java Core, Java 8, Collections, OOP, Design Patterns, JUnit. ✅Databases: JDBC, Hibernate, RDBMS (PostgreSQL, H2, MySQL) ✅VCS: Git, Travis CI ✅Web Development: Servlets, Tomcat, JSP, HTML/CSS, XML, JSON, JSTL ✅Spring: Spring Core, Spring Web, Spring Security, SpringBoot ✅Tools & Libraries: Maven, JUnit, Mockito ✅Operating systems: Windows ✅SOLID, TDD, CRUD.IDE: IntelliJ Feel free to get in touch, I'm quick to respond!
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Web Development
    Web Application
    Back-End Development
    Hibernate
    MySQL
    PostgreSQL
    Spring Security
    Spring Boot
    Java
  • $30 hourly

    • 4.7/5
    • (70 jobs)
    I have 11 year working experience in video streaming, web and mobile app development. I have developed several custom modules for video transcoding, live recording, chat, video conference, IP Camera re stream, IPTV channel re stream and several others. I like to give demo or POC first and then start real project this makes vision more clear to both party( buyer and service provider). I have completed my Post Graduation in year 2007 and after that I started my professional career in Java Struts/Spring and Hibernate after that I started core Apps of Andriod in year 2010 and then started XMPP based chat Apps for IOS. Video Streaming: I have been working with WOWZA, Red5 and FMS since year 2009. Now I started NODE JS, React JS, Socket JS HTML5 with WebRTC this is because this technology growing rapidly and modern browser is also ready to support this tech. I believe success only needs hard work and honest attempt. I do commit my 24x7 time if things going in complex situation.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Video Conversion
    Adobe Flash
    Wowza Media Server
    Video Stream
    XMPP
    FFmpeg
    Red5
    WordPress
    PHP
    iOS Development
    Java
    WebRTC
    Node.js
  • $100 hourly

    • 5.0/5
    • (14 jobs)
    Hi there! I am an experienced Python developer with a focus on algorithmic trading. I have over 5 years of professional experience in the field and a strong background in computer science. I have a strong foundation in Python programming and am proficient in various libraries and tools such as NumPy, Pandas, CCXT, Backtrader, Quantlib, Postgresql, MongoDB, Django, FastAPI, CI/CD, and Nginx. I have extensive experience in building and implementing trading strategies, analyzing market data, and using automated trading systems. In addition to my algorithmic trading skills, I have also worked on a wide range of projects, including web development, data analysis, and machine learning. I am a proactive and detail-oriented developer who is always eager to learn and take on new challenges. I have excellent problem-solving skills and the ability to work effectively in a team or independently. In my previous roles, I have successfully delivered projects on time and within budget, and have received positive feedback from clients for my high-quality work and dedication to meeting their needs. I am excited to bring my skills and experience to your project and contribute to its success. Thank you for considering my profile.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    PostgreSQL
    MongoDB
    Celery
    NGINX
    Django
    Ubuntu
    CI/CD
    Flask
    Redis
    pandas
    Python
    NumPy
  • $38 hourly

    • 4.9/5
    • (43 jobs)
    💡 If you want to turn data into actionable insights or planning to use 5 V's of big data or if you want to turn your idea into a complete web product... I can help. 👋 Hi. My name is Prashant and I'm a Computer Engineer. 💡 My true passion is creating robust, scalable, and cost-effective solutions using mainly Java, Open source technologies. 💡During the last 11 years, I have worked with, 💽Big Data______🔍Searching____☁️Cloud services 📍 Apache Spark_📍ElasticSearch_📍AWS EMR 📍 Hadoop______📍Logstash_____📍AWS S3 📍 HBase_______📍Kibana_______📍AWS EC2 📍 Hive_________📍Lucene______ 📍AWS RDS 📍 Impala_______📍Apache Solr__📍AWS ElasticSearch 📍 Flume_______📍Filebeat______📍AWS Lambda 📍 Sqoop_______📍Winlogbeat___📍AWS Redshift 5-step Approach 👣 Requirements Discussion + Prototyping + Visual Design + Backend Development + Support = Success! Usually, we customize that process depending on the project's needs and final goals. How to start? 🏁 Every product requires a clear roadmap and meaningful discussion to keep everything in check. But first, we need to understand your needs. Let’s talk! 💯 Working with me, you will receive a modern good looking application that will meet all guidelines with easy navigation, and of course, you will have unlimited revisions until you are 100% satisfied with the result. Keywords that you can use to find me: Java Developer, ElasticSearch Developer, Big Data Developer, Team lead for Big Data application, Corporate, IT, Tech, Technology.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Big Data
    ETL
    Data Visualization
    SQL
    Amazon Web Services
    Amazon EC2
    ETL Pipeline
    Data Integration
    Data Migration
    Logstash
    Elasticsearch
    Apache Kafka
    Apache Spark
    Apache Hadoop
  • $30 hourly

    • 4.7/5
    • (7 jobs)
    Hi, Thanks for visiting here! I've been working as a Full Stack Developer for a long time. And, this is what i like to do 24/7! I've many skills which includes these - 1. HTML/HTML5 2. CSS/CSS3 - Bootstrap 3. JavaScript - jQuery, jQuery UI, AngularJS, ReactJS, NodeJS 4. Java , Spring, Springboot, SpringMVC, Spring Batch, 5. PHP - Wordpress, Laravel, CodeIgniter 6. C, C++, C# 7. Database - MySQL, Oracle, MongoDB, Vertica, MarkLogic 8. Git, GitLab, Bit-bucket, SVN 9. JIRA 10. Jenkins 11. CI/CD 12. Apache Tomcat 13. Payment gateways: Paytm, RozarPay, Paypal 14. AWS Just give me a chance to work with you. Trust me, if you hire me once, you will hire me again and again! If you have time, read some feedback. Thank you. Mahesh Phatangare
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Web Services Development
    Selenium
    JavaScript
    ExpressJS
    Amazon Web Services
    Web Development
    Java
    HTML
    Spring Batch
    MySQL
    MongoDB
    Hibernate
    Node.js
    Spring Boot
  • $20 hourly

    • 5.0/5
    • (14 jobs)
    Hello i am a Programmer and Developer. I have a lot of Experience in Web development, Web designing and desktop application development in any programming language. The Main Programming languages in which i have a experience are: 1) Java 2) Java Swing 3) Mysql, SQL 4) c/c++ 5) c# 6) MVC.Net 7) HTML, HTML5 8) CSS, CSS3 9) Bootstrap 10) Java Script, JQuery I also do some projects that are now in market. Projects that i will done are: 1) Inventory Management System (in Java Swing and MySql) 2) Railway Management System (in PHP, CSS, HTML, BootStrap, MySql) 3) Grocery Management System (in MVC.NET, CSS, HTML, Bootstrap, MySql) My Main focus is give you a good result according to your requirements. And i will try to complete project and give it to my Client before the deadline. Hope you get a good result after hiring me. Thanks!
    vsuc_fltilesrefresh_TrophyIcon Core Java
    JavaFX
    Spring MVC
    Core ML
    MySQL Programming
    Spring Boot
    Java GUI
    Android App Development
    Desktop Application
    Python
    C
    Mobile App Development
    Java
    C++
    JUnit
  • $30 hourly

    • 5.0/5
    • (26 jobs)
    I have been working as a Java developer for 5 years. As I am new to Upwork, completing jobs according to the client's requirements is not only my duty but it is my necessity. Client satisfaction will be my first preference. It's important to me to build long term relationships with clients, so I'm primarily looking for long term projects. I'm flexible with my working hours and am happy to work closely with any existing freelancers you work with. I have 5+ years of experience in Web application development, Blockchain, Trading Platforms, Web Scraping, Microservice architecture, and Scripting. Worked on E-commerce apps, GPS Monitoring Servers, Crypto Exchanges, Blockchain. Experience on OAuth2, Facebook, Google, Twitter, Google Maps integration and Spring Security. Please connect with us for a safe business and for better product delivery on time. Instead of making false promises or writing big slogans let's start work.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Jakarta Server Pages
    Git
    Web Application
    React
    Vue.js
    Angular
    RESTful API
    Ext JS
    OAuth
    Spring Security
    JavaScript
    Java
    Scripts & Utilities
    Microservice
    Spring Boot
  • $10 hourly

    • 5.0/5
    • (3 jobs)
    7+ years of experience in Web/Mobile/Desktop Application testing, Cross-Browser/Platform Testing, API/REST, TestPlan/Case Documentation, Usability Testing, Product Requirements, & many more with much more tools and addons. Experienced Full Stack developer / programmer with 7+ experience ( Wordpress, Vue.JS/ Angular 2-7/ Meteor.JS/ Backbone/ Express/ Laravel/ GraphQL/ React/ Redux/ Typescript/ Wordpress /PHP / MySQL / HTML / CSS / JS / Magento 1-2) capable of creating advanced WordPress websites and custom web applications. I always focus on implementing pixel-perfect and responsive UX/UI matching to the designs. Significantly I am familiar with JavaScript Frameworks, including Angular, React.js, and NodeJS. My Skill Set: - CMS ** Magento, OpenCart, WordPress, Squarespace, Wix - Development Languages: ** HTML5, CSS3, SQL ** JavaScript, TypeScript, ES6/ES7 - Responsive UX/UI development ** UI Libraries - Bootstrap 3/4, Semantic UI, Material UI, Kendo UI ** CSS Skills - SCSS/SASS, FlexBox, Animations - Javascript Development ** AngularJS - Angular (1, 2, 4, 5,6,7), Angular-CLI, Angular-Material ** ReactJS - React.js, Redux, React Native, Saga, Thunk, ** NodeJS - NodeJS, ExpressJS, GraphQL, RESTful API ** Code styling - TS Lint, ES Lint, JSHint. ** Testing Frameworks - Enzyme, Jest, Mocha, Chai, Protractor, Jasmine, Karma - Database Experience ** No-SQL - MongoDB ** SQL Database - PostgreSQL, MySQL, Oracle, SQLite - Web Hosting * AWS EC2, Heroku, Digital Ocean, Ngnix, Godaddy - Project Management Tools and Version Control * Agile/Scrum, JIRA, Asana, Pivotal Tracker, Trello * GitHub, Bitbucket, GitLab
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Tortoise SVN
    Git
    CakePHP
    CodeIgniter
    WordPress
    Node.js
    PHP
    AngularJS
    API
    MySQL
  • $10 hourly

    • 5.0/5
    • (12 jobs)
    I am a passionate software developer focused in providing my clients robust mobile and web application. I am working in this field for the past 8 years and have gained expertise in following type of apps: ◆ On-Demand service based apps ◆ Photo based app ◆ Video based app ◆ Social networking Apps ◆ Location based apps ◆ Utility Apps ◆ Geofencing Apps ◆ Restaurant Apps ◆ Booking Apps I have extensive knowledge in mobile app development and this includes all the service from gathering requirements, wireframes, mockups, UI/UX, back-end to deploying apps on stores. Technologies I have used for development are : ◆ For Mobile Apps : Kotlin, Android Studio, Android SDK, Swift, Objective-C, Xcode, AV foundation, Cocoa Touch, React Native, Flutter, Ionic. ◆ For Web : React, Wordpress, Angular, Vue, HTML, CSS, Javascript, Magento, Shopify, Ruby ◆ For Back-end : MongoDB, Firebase, Node.js, Laravel, PHP, Python, Django Furthermore, I am proficient with RESTful APIs, JSON format, Git, Push notifications and make use of architectural patterns—MVP, MVC, MVVM. Let's connect to discuss how I can help to meet your goals and contribute to your projects in the best way I can!!
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Review or Feedback Collection
    Map Integration
    Python
    PHP
    MongoDB
    Laravel
    Kotlin
    Android App
    Apple Xcode
    User Authentication
    Firebase
    In-App Purchases
    iOS Development
    Swift
    Social Media Account Integration
  • $10 hourly

    • 5.0/5
    • (8 jobs)
    Hello I have five years of experience in Android applications for mobile and tablet devices. I have profound programming knowledge in JAVA, Kotlin all App Development languages also know XML, PHP, dart, C, C++, HTML, etc. Expertise fields on App development: • Java, Kotlin, XML • Retrofit2, Volley, RxJava, OKHttp, Jsoup, Fast-Android-Networking, ion • MVVM, jetpack components,DI • Google Map, Google Places • SQLite, Firebase Realtime, Realm, ROOM Database • Encryption • Social networks API: Facebook, Twitter, LinkedIn, Instagram, Firebase Auth, Goggle auth • Crashlytics, • Push Notifications • In-App Purchase, Stripe SDK, Paytm, CCAvenue, Razorpay, etc. • Picasso, Glide. • Firebase ML • IoT Device  • etc. Thank you.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Django
    AWS Application
    RESTful API
    Serverless Computing
    AWS Lambda
    Python
    Mobile App Development
    Firebase
    Android
    Dart
    Android App Development
    Kotlin
    Java
  • $30 hourly

    • 4.2/5
    • (46 jobs)
    I'm a professional and passionate Mobile and Web developer. ✔ Excellent and Outstanding coding skill, ✔ Pixel perfect Mobile App UI design, ✔ Client 100% Satisfaction! I am a highly-qualified professional with 7 years experience in developing mobile applications for Android, iPhone, iPad. I have successfully launched over 45+ projects in various domains and technologies, ranging from simple apps to complicated projects. My main objective is a process-oriented approach that combines experience and creativity to find the most productive solutions and succeeding results. I am proficient enough in working in close collaborations with offshore clients as well. Flexibility and keeping ahead with technologies are my strengths, so I can guarantee the high quality of the work done. Experience with Web Development - HTML - JavaScript - CSS Experience with iOS technologies: - Xcode, Objective-C- databases: CoreData( MagicalRecords including), SQLite - internet and server side interactions(AFNetworking library): REST API, SOAP, JSON, Parse, Google API - maps: iOS MapKit Framework, Google Maps API, Yandex SDK - social networks: Twitter API, Facebook SDK, VK SDK - storage: local storage, cloud storage (icloud, dropbox) - multimedia (photo, video, audio)- tools: Redmine, Git, SVN, SoapUI, DBMS (database management systems), Crashlytics - notification/reminders: Local Notifications / APNS,EventKitUI - in-app purchases - iAd Experience with Android technologies: - Android studio, Java- Google Play Services and Patterns - Android libraries: Android Support Design Library, Android Support Library (v4, v7 appcompat, v7 cardview, v7 recyclerview), ActiveAndroid, RxJava, Retrofit, Picasso, UIL, ButterKnife, EventBus, Amazon - databases: Amazon DynamoDB, SQLite, Couchbase Lite Android - storage: local storage, cloud storage (Amazon S3, Couchbase Lite Android, dropbox) - multimedia (photo, video, audio) - tools: - Redmine, Git, SVN, SoapUI, DBMS (database management systems), Crashlytics - internet and server side interactions(AFNetworking library): REST API, SOAP, JSON, Parse, Local/Push-Notifications, Google API, GSON, GeoJson, Amazon SNS - MVP - Google Android Maps Utils - in-app purchases
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Autodesk 3ds Max
    3D Animation
    Unity
    WebRTC
    Firebase
    iPad App Development
    iOS Development
    Android
    Java
  • $60 hourly

    • 5.0/5
    • (6 jobs)
    - Software Developer with more than 13 years of experience. - Proficiency in Cross-platform and High Load systems development. - Good telecommunication and network technologies knowledge. - Expert in full stack development with main focus on backend. - Professional knowledge of microservice architecture. - Excellent team player with remarkable communication skills. My skill sets include: ▪ Technologies: Java/Kotlin, Apache ActiveMQ, Google Guice, Jersey, gRPC, JDBI, Hibernate, MultiThreading, Jackson, Java Network API, RxJava. ▪ SQL Database: MySQL, Microsoft SQL. ▪ NoSQL Database: Amazon DynamoDB. ▪ Application Service: Apache Tomcat, WildFly, Glassfish, Jetty. ▪ Build automation: Maven, Gradle, Apache Ant. ▪ Revision control: Git / GitLab / Bitbacket, SVN, CVS. ▪ Continuous integration and delivery: TeamCity, GitLab CI/CD. ▪ Cloud technologies: Amazon (Aurora MySQL, DynamoDB, SQS / SNS messaging, Cognito, CloudSearch ). ▪ Test-driven development: JUnit, Mockito. ▪ Operating systems: Linux, Windows, FreeBSD.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Java EE
    REST
    Microservice
    Multithreaded Programming
    Apache Tomcat
    MySQL Programming
    Swing
    SQL
    Java
  • $36 hourly

    • 5.0/5
    • (37 jobs)
    With over 5 years of industry experience, my expertise are web & mobile applications (iOS/Android), project management (agile) and DevOps — ensuring seamless development processes. Skills: - Django/Python - React JS - React Native & Flutter - VueJS - HTML/CSS/JavaScript (Bootstrap) - WordPress - Third-party integrations Why collaborate with me? ✅ Technical Expertise: Proficient in diverse technologies to deliver cutting-edge solutions. ✅ Project Management Excellence: Ensuring on-time delivery and smooth execution. ✅ Valuable Insights: Providing strategic suggestions to enhance your business. ✅ Quality-Driven Approach: Building scalable, maintainable, and efficient solutions. ✅ Client Satisfaction: Your success is my top priority. Throughout my career, I helped companies achieve remarkable success, generating millions in revenue and boasting thousands of active users. If you're looking for a dedicated and skilled developer who takes ownership of projects and fosters open dialogues within the team, I'm here to help. Let's work together to create exceptional outcomes. -------------------------------------------------------------------------------- KEYWORDS: Website Development | Full Stack Developer | Django | Backend | Frontend | Web Application | Google Cloud Platform GCP | Amazon Web Services AWS | Docker | Git | Github | Jira | Trello | Project Management | Team lead | Product Development | Jinja | Django Rest Framework | Flask | FastAPI | React | Vue | NodeJS | NuxtJS | Heroku | Tech | Unicorn | Ecommerce | SEO | Google Analytics | Payment Integrations | Google Maps | Shipments | logistics
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Google Analytics
    Database Architecture
    Python
    Django
    Java
    iOS
    WordPress
    PHP
    React
    React Native
  • $20 hourly

    • 5.0/5
    • (2 jobs)
    With a diversified experience of 4 years as a Python/JAVA/Django developer working in cross-cultural global teams, I have successfully completed various projects, from design to implementation to integration. Python Django, Flask, JAVA, PostgreSQL/SQLite, Elasticsearch, REST, and DevOps tasks (CI/CD, Docker, etc.), AWS, and Azure are all part of my day-to-day work. I would love to take on any challenge to fulfill the client's requirements. PYTHON | FastAPI | DJANGO | FLASK | VIRTUALIZATION | API | DATABASE DEVELOPMENT | JAVA | HTML I have developed entire front-end and back-end modules using Java and Python web frameworks and have been actively involved in maintenance, redesign, project management, and the development of different web applications. Working with a Scrum process and agile methodologies, I have developed a variety of websites, including educational platforms, e-commerce, file-sharing, job portals, and various others. I have a creative and performance-oriented work approach and I am adept at directing software development. Being inspired by market-leading technology providers and constantly striving to keep up with the most recent developments in software design, I am also quite skilled and enthusiastic when it comes to UI and UX design. My competencies include but are not limited to: ✪ Development of intuitive and cloud-based software products and applications using clean object-oriented design. ✪ Development of custom Python applications, keeping in mind your business’s key objectives while ensuring data security and protection and identifying data storage solutions. ✪ Strong focus on implementing agile, secure, scalable, performance-based Python development practices. ✪ Designing and creating RESTful APIs for internal and partner consumption ✪ Experience with databases such as MySQL or PostgreSQL or MongoDB or Elasticsearch ✪ Design and development of data management systems using MySQL ✪ Debugging and troubleshooting web applications. Skills Python, JAVA, Python Script, Python Requests, Django, JavaScript, PHP, HTML5, CSS3, My SQL, PostgreSQL, jQuery, AJAX, Network Security, API Development, API Integration, Project Management, Scrum, Backend & Front Development. ✪ I am also a Splunk Certified Professional. I have experience with Splunk Enterprise Security, Splunk Mission Controls, Splunk User Behaviour Analytics With a strong background in a disciplined software development lifecycle process (SDLC) and excellent analytical, programming, and problem-solving skills, I am all set to help you build a winning solution. I will be delighted to work with you on your project whether you are seeking a stand-alone developer or expanding your existing team. Let’s talk.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Node.js
    Flask
    Python Script
    API Development
    RESTful API
    Python
    API
    Django
    Adobe Photoshop
    Java
    Selenium WebDriver
    Data Mining
    Database Architecture
  • $38 hourly

    • 5.0/5
    • (13 jobs)
    Hello there! I am a research engineer and freelance software developer in the field of robotics and AI. My expertise includes Perception, Computer Vision, Deep Learning and AI Planning. I hold 7+ years of Robotics background involving applications from Mobile Robotics, Arm Manipulators and Humanoid robots. I also own good records on collaborating with clients and customers, understanding the needs of each project, managing them in demanding schedules and delivering them on time. Either short-term or long-term contracts, feel free to drop a message to discuss the project beforehand.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Algorithm Development
    Robotics
    Git
    Docker
    Robot Operating System
    MATLAB
    Linux
    Computer Vision
    Python
    C++
  • $25 hourly

    • 5.0/5
    • (13 jobs)
    I'm a full-stack Ruby on Rails developer with over 5 years of programming experience. Since 2017, It's a pleasure for me to design applications that have aided, developed and added value to digital brands and a variety of projects requiring both front-end and back-end development. I'm also familiar with AWS services. Scrum was used to develop almost every project I worked on. My technology stack: Backend: Ruby, Ruby on Rails Frontend: JS, jQuery, CSS3, HTML5, React, Angular, Bootstrap 3 | 4 Databases: MySQL, PostgreSQL, Redis, Elasticsearch Testing: RSpec. Payment system integration: Stripe, Paypal, Braintree, etc Version Control: Github, Bitbucket Restful API, Microservices Development Others: Linux My approach: - a problem solver - familiar with best programming practices and agile project development Other: * Experience with Shopify theme and App Development * Experience with Agile Methodologies * Designing of high load web apps * Experience with Ecommerce Systems * Rspec Testing Thank you for reviewing my Upwork profile. Looking forward to working with you. Ali Haider
    vsuc_fltilesrefresh_TrophyIcon Core Java
    JavaScript
    Shopify Plus
    Shopify Theme
    Shopify Apps
    Shopify
    Ruby
    Database Management
    API Development
    Database Architecture
    Node.js
    Elasticsearch
    SaaS
    Angular
    React
    Ruby on Rails
  • $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 : 7 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 * Snowflake
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Web Development
    RESTful API
    Software Architecture & Design
    MongoDB
    Elasticsearch
    Spring Framework
    Agile Software Development
    AJAX
    HTML5
    JavaScript
    AngularJS
    Grails
    React
    Java
  • $10 hourly

    • 4.5/5
    • (43 jobs)
    Hello Dear Client, I am Jay Trivedi. I'm always looking forward to working with a client and solving the problem that they are facing. Feel free to contact me any kind of project which is related to my skill sets. About Me: • I have 2+ Years of experience. • I am Fast Learner. • I develop Websites, BOTs, Automation, Web Scrapers and much more... • I also deploy app on Docker, Kubernetes using cloud providers such as AWS, GCP, Azure, Linode, DigitalOcean and more... • I also design DataBases and Systems. • I completed 25+ Projects. • I provide Full Stack service. Why My Services? 1. I provide support for the service you bought even after the contract ends. (Based on the project and size) 2. Available for Long Term project. 3. Ready to provide Long-Term service. 4. Eager to provide solution for your startup and company. My Services: 1. Angular Websites 2. Backend Development in Django, Flask and FastAPI. 3. API Development 4. Browser Automation 5. Web Scrapers & Multithreaded web scrapers 6. API Integrations 7. Custom BOT 8. Zapier development 9. Power Automate 10. UiPath 11. Google’s API Integration 12. Telegram, Slack, Discord and WhatsApp BOTs. 13. Deployment of Any Website, BOTs, Scrapers etc.. My Skills: • Programming Languages Python, TypeScript • Frameworks Django, Flask, FastAPI, Angular • Front-end HTML, CSS, Bootstrap • Database MySQL, PostgreSQL, MonogoDB, SQLite, Redis • DevOps Docker, Jenkins, Kubernetes, AWS, GCP, DigitalOcean, Azure • Automation Selenium, UiPath, Automation Anywhere • Tools Git GitHub Postman Linux
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Python Script
    Bot Development
    API
    Django
    Database
    Angular
    DevOps Engineering
    MongoDB
    MySQL
    Flask
    ETL Pipeline
    Scripting
    Selenium
    Automation
    XML
    Python
  • $20 hourly

    • 4.6/5
    • (25 jobs)
    ☑️ 8+ years of experience ☑️ Proven Track Record of Accomplishment ☑️ 41 Project/Application Developed ☑️ B2B Verified Reviews ☑️ Available Full Time for Mobile Development ☑️ Flexible hours of discussion ☑️ Available on IM, in case, needed! 🌟 Clear communicator 🌟 Fast delivery 🌟 High-performance work 🌟 Satisfaction guaranteed 🌟 100% Job Success. 🏴 Skill Set 🏴 ⭐️ Front-End: Angular, React, Vue.js, Bootstrap, LESS, HTML/CSS ⭐️ Back-End: Python, Django, Laravel, ROR, Node.js ⭐️ Native programming: iOS8,9(Objective-C, Swift), Android (Java, Kotlin) ⭐️ MAC Plugins Development ⭐️ Chatting & Messaging: XMPP, Jabber, Socket, OpenTok Web RTC ⭐️ Payment Integration: Paypal, Credit Card, Braintree, klarna, Stripe ⭐️ Video, Photo, News sharing: Live-Stream, Multitask, Real-time upgrade, Red5, Wowza ⭐️ Video, Audio, Image processing: OpenGL, OpenCV CoreAudio, Bass ⭐️ Modern, flexible, clean and fresh UI animation effects ⭐️ Dynamic customize User Interface modules and APIs ⭐️ Communication: Excellent written & spoken English skills ▶️ Web service and Backend programming: AWS lambda, JSON, firebase, AWS, JSON, XML, REST, SOAP APIs ▶️ Databases: SQLite, Coredata, MySQL, SQL, MongoDB, Amazon RDS ▶️ Social SDK integration: Facebook, Twitter, Foursquare, Instagram, Tumblr, Google+, Pinterest 🔘 Sphere of experience 👉 Business Automation App | Swift, Kotlin 👉 Geo-Location App | Swift, Kotlin 👉 Health and Fitness App | Swift, Kotlin 👉 Video and Audio Stream App (Real TIme) | Swift, Kotlin 👉 Taxi Hiring App - Uber clones | Swift, Kotlin 👉 News, Event and Schedule App | Swift, Kotlin 👉 Booking and Service App | Swift, Kotlin 👉 Photo and Video Social Chat App | Swift, Kotlin 👉 Shopping App | Swift, Kotlin 👉 Real Estate App | Swift, Kotlin 👉 Calendar/QRcode scan App | Swift, Kotlin 🔘 What more I can offer 👉 Security Audits 👉 Project Architecture Consultancy iOS, Android 👉 SQLite database, Push notifications, Back-end Web services 👉 Maintenance and Updating service of existing mobile applications (iOS, Android) 👉 Free submitting on respective stores (Apple, Google) 👉 Quality Assured Deliveries 👉 Maintenance & Support for both iOS, Android 💾 Source code and project management: ▪️ Git, GitHub, BitBucket ▪️ JIRA, Slack, Redmine, Trello ▪️ TestFlight distribution, AppStore submission ❇️ If I work for you, I'll use all of my skills to do whatever you need ❇️ Drop a message 📨 Or Invite 🏆 for the task; will be happy to bring best to it through my skills 🤗
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Objective-C
    Hybrid App Development
    Android Things
    iPhone UI Design
    Mobile Programming
    iPhone App Development
    Mobile UI Design
    Kotlin
    Swift
    Laravel
    Android App Development
    iOS Development
  • $10 hourly

    • 5.0/5
    • (3 jobs)
    I'm a software engineer with experience in web and mobile development using HTML, CSS , JavaScript, Liferay DXP, React.JS and React Native. I can help you building your templates, websites and mobile apps from scratch and customizable according to your needs.
    vsuc_fltilesrefresh_TrophyIcon Core Java
    Machine Learning
    Figma
    React Native
    Adobe XD
    Liferay
    Database
    jQuery
    CSS
    Bootstrap
    React
    Apache FreeMarker
    Python
    JavaScript
    OpenCV
    HTML
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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. 


 
 
 
     
 
 
 
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