Top Upwork Freelancers

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  1. Oleksandr K.

    Oleksandr K. Agency Contractor

    Mobile, Desktop and DSP developer

    Ukraine - Tests: 6 - Portfolio: 10

    Over the last years I've been developing apps for iPhone, although, most of the apps I developed are still under NDA. Previously I've been developing DSP solutions (mostly digital image and audio processing algorithms) and industrial control systems. I like iPhone development, as there is some challenge because of the limited processing capabilities, but it is still fun. My core competencies are DSP systems and along with all sorts of non-web apps. I also have experience in the following areas: software architecture, OOP, FPGA-development.

    Associated with: IDAP Group

    $33.33 /hr
    555 hours
    4.76
  2. Andrei Istomin

    Andrei Istomin Agency Contractor

    Java/Grails Developer

    Germany - Tests: 4 - Portfolio: 6

    Since start of my career I've been using a lot of technologies/languages/frameworks for creation varied types of software in different areas of human life. Last years I'm focused on server side issues, including multi-threading, concurrency and complex business logic problems. Mostly I work with Java technologies(including Grails, Spring, Hibernate and other frameworks). I like to work with serious, adequate and honest clients. I'm happy if I can help somebody to create something meaningful. I'm opened for technologies and tools that I've never used before. It's very interesting to me. It allows me to open areas of life that are new to me and to get experience that I've never had before. Feel free to contact me if you think that my skills and experience might be useful for you.

    Associated with: AI Rising Soft

    $35.56 /hr
    5,636 hours
    5.00
  3. Sergio Pulgarin

    Sergio Pulgarin Agency Contractor

    Software Engineer

    Colombia - Tests: 8 - Portfolio: 3

    Providing clients around the world with high quality services in Software Design, Engineering and Development. I have a degree in Electronic Engineering; I have excellent Software development, and Networking skills. My area of expertise is design, engineering and development of Software applications with Networking functionality, use and design of functionality exposed through web APIs. Additionally, I'm experienced in the following areas: - Networking applications: TCP Servers, Sockets, Network requests, Web viewers, Web APIs. - Webkit development for full integration of Web and Desktop applications. - GUI development: Native looking user interfaces. - Filesystems: Creating, reading and writing, text and custom data types. - SQL Database handling for desktop and web applications. - SkypeKit application development. - Server side web applications using Django. I have experience in Object-Oriented design and use better coding practices; I always keep in mind readability and reusability. I also deliver documented sources, when required.

    Groups: LoginRadius

    Associated with: SOLID, GSOLID

    $33.33 /hr
    732 hours
    4.95
  4. Ostap M.

    Ostap M. Agency Contractor

    Java Developer

    Ukraine - Tests: 3 - Portfolio: 3

    I am Java Developer with more 3 years of experience. I have developed many projects using modern frameworks and able to learn new one quickly if needed. Before I worked as team member developing networking client-server application and some web projects using MVC frameworks or plain JSP/Servlets. Languages : Java, Python Technologies : JSP, Servlets, JDBC, Web Services, REST Databases : MySQL Frameworks/Libraries: Spring, Hibernate(JPA) , JUnit, JavaFx, Netty Design skills: OOP, Gof patterns, UML Software Development Methodology: Agile, XP, TDD Tools: Maven, SVN, Git, Jenkins IDE: Intellij Idea, NetBeans Other: HTML, JavaScript, jQuery, XML, JSON, JIRA

    Groups: Corona Labs

    Associated with: Progost

    $22.22 /hr
    189 hours
    4.15
  5. Milos V.

    Milos V. Agency Contractor

    Software engineer for web technologies (PHP/JAVA/HTML/CSS/) EXPERT

    Serbia - Tests: 2 - Portfolio: 5

    During my career I have developed several web applications such as web shops, poll gathering web applications, small websites and others using fololowing technologies :(D)HTML, CSS, PHP, Java , JavaScript, MySql, Adobe Flash etc. Also I am familiar and have experience with software modeling toos such as power designer. In regards to my work history, I have also worked as IT manager for 3 years for Exit Festival's official tourist services and had collaboration with other companies, payment systems, banks and individuals. There I've learned how to lead a team of programmers and web designers and also I received knowledge and experience in business management, bussines processes and routines and how to support them with applications and software in general. My goal is creating top quality software which solves issues, helps in accomplishing tasks in easier quicker and cost effective way and makes things possible such as online shopping, transactions, marketing etc. Therefore I seek opportunities in which I find these challenges. My long term goal is to become the one of the best software consultants/engineers/developers/architects and help businesses grow and multiply with creativity and effectiveness in all their aspects.

    Associated with: WeDoQa

    $27.78 /hr
    1,613 hours
    5.00
  6. Drew Ulmer

    Drew Ulmer Agency Contractor

    [Upwork Top 5 Percent] Professional Rails Developer

    United States - Tests: 4 - Portfolio: 6

    When you hire me, you're hiring a top 5% Upworker with multiple successful projects and universally happy clients. I am an expert Ruby and Rails developer with more than 6 years of successful projects with Ruby on Rails versions 2.3 through 4.x. I enjoy working on everything from ecommerce to line of business applications and I specialize in identifying and fixing security issues. I can occasionally be found on the #rubyonrails freenode IRC channel and my github can be found under the username latortuga. I have contributions to major open source projects including Ruby on Rails, Devise, ActiveAdmin, cache_digests, warden, spree, and zeus. I am generally interested in Ruby or Rails development proposals, provided they include information about the actual project and not merely a list of skills.

    Groups: Twilio

    Associated with: Unabridged Software

    $150.00 /hr
    1,096 hours
    4.98
  7. Serhiy Kanyuka

    Serhiy Kanyuka Agency Contractor

    I like to mix technologies to get the best solution for client.

    Ukraine - Tests: 7 - Portfolio: 5

    I am developing for more than 12 years and participated in development of big projects (tech lead, project manager,developer) and developed small projects on my own. There were native client-applications for Windows (C++, C#) and Linux as well as servers and web applications (Linux, Windows). For the last 4 years I was also working with architecture design and development in few areas like: Vending Machines Web Services and Web Application in Web Clouds (AWS) Internet Payments Distributed Databases Microcontrolers internet of things set-up and monitoring of Linux/Freebsd servers and developing the web-applications. I have quite a large experience in developing and debugging so I can look at project deployment as developer and as administrator that gives better and faster result. The learning of new technology and it’s intergation is my favourite activity that’s why I will understand you easily and integrate in your project team. My skills: OS: Busybox, Linux, Debian, RedHat - expert, FreeBSD and Windows Server - proficient Web servers: Apache, Nginx, Tomcat, haproxy Database servers: Mysql, Postgresql CMS:Yii, CodeIgniter Advertising: OpenX, AdSense Scripting: bash, perl, php, javascript Languages:C, C++ SDK:Qt Virtualization: Vmware esxi/server Other: standard network services (DNS, DHCP, Samba, SVN, http proxy, backups, monitoring etc), firewalls and routers I have work with hosting: AWS, hetzner.de, rackspace, amh.com, advancedhosters.com

    Associated with: Krechet Company

    $24.44 /hr
    7,812 hours
    5.00
  8. Vladimir G.

    Vladimir G.

    Trading related projects

    Russia

    Tradestation (EL) Multicharts (PL) NinjaTrader (NS) Wealth-Lab (WS/C#) AmiBroker (AFL) MetaTrader (MQL) Thinkorswim (TS) eSignal (EFS) Dealbook 360 (CTL)

    $55.56 /hr
    0 hours
    4.84