Top Upwork Freelancers

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  1. David Knell

    David Knell

    Senior telecoms developer/CTO

    United States - Tests: 2

    I've been developing software commercially for more than a quarter of a century, both as an employee of large organisations (IBM) and, to a greater extent, as my own boss. I've built and sold two businesses along the way, learning a great deal from having done so. My focus has been on telecoms. I developed TDM IVR systems based around Aculab and Dialogic cards in the late 1990s, and have, more recently, been involved in developing IP solutions using Asterisk, Kamailio and FreeSWITCH. These have included an IP Centrex platform (Asterisk and SER), a carrier-grade softswitch (FreeSWITCH) and various IVR solutions (Kamailio and FreeSWITCH). I'm fluent in a number of languages, including C, PHP, Perl, C# and Javascript, am happy to develop on Windows or Linux and have been using Agile development methods - in particular, release early and often - since before the term Agile was coined. I'm experienced with managing small teams of developers, and understand the importance of delivering the agreed product on time and within budget.

    $75.00 /hr
    3 hours
    5.00
  2. Faisal A.

    Faisal A. Agency Contractor

    Experienced Software Developer

    Pakistan - Tests: 2 - Portfolio: 5

    I have an overall experience of 15 years. I am currently working as a member of a fully distributed team for YouNeedABudget.com since March 2012 (http://www.youneedabudget.com/company/team). I specialise in backend server side development using Node with Javascript/Typescript. I have experience of working with both relational databases (PostgreSQL) and NoSQL databases (MongoDB). I have also done some front-end work using both AngularJS and EmberJS. I believe in test driven development, and use Karma and Chai extensively for unit testing. I have worked with Jenkins for CI, and use Git for SCM. I also use Vagrant for setting up development environments. I have worked with Heroku for application deployments. In the past, I have worked with Adobe Flex and Microsoft .NET technologies extensively.

    Groups: Application Developers Alliance

    Associated with: ByteSmiths

    $66.67 /hr
    5,524 hours
    5.00
  3. David H.

    David H. Agency Contractor

    Citrix and Virtualizaion Systems Engineer

    United States - Tests: 3

    I am a specialist in remote application delivery, VDI and cloud based computing. I have been working with Citrix products and some of their competing products and add-ons, from back in the Winframe NT4 Terminal server days, all the way up to the current Xenapp 6.5. I work full time for a major NYC hospital on the Citrix Engineering team, responsible for 200 + servers supporting a 24/7 mission critical environment. I have engineered delivering hundreds of applications to users on every type of device out there (PC, Macs, Thin clients, iPads, Androids, HTML5 browsers, etc.). I have a legacy MCSE for Windows 2000, and years of experience with Windows Server 2003, 2008, and 2008 R2. I have extensive experience with Active Directory group policies, Proxy servers, Web Servers, and Logon scripts using WSH, CMD files, and PowerShell. I have recent training in Microsoft App-V, Citrix Xenserver, Amazon Web Services, VMWare vSphere 5, OpenVPN and VDI-in-a-Box. I have recent part-time contracting experience providing Windows Server 2008 R2 IaaS servers in the cloud with Amazon AWS, OpenVPN, and a proof of concept project to provide SaaS using Xenapp and VDI for end users of a small business, including a custom web portal for them to reach their desktop from anywhere.

    Associated with: 3 Bay Consulting, LLC Agency

    $48.89 /hr
    72 hours
    4.99
  4. 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
  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. Alexander G

    Alexander G Agency Contractor

    Software Developer

    Armenia - Tests: 5 - Portfolio: 6

    Professional Experience 02.2013 to present Simply Technologies Position: Senior Software Developer Yerevan, Armenia 02.2008 to 02.2013 Macadamian AR Position: Senior Software Developer Yerevan, Armenia 08.2006 to 02.2008 Synopsys LLC (SEG Department) Position: Software Developer Yerevan, Armenia 08.2002 to 06.2004 HPLA LLC Position: Software Developer Yerevan, Armenia Projects Yidio video search engine Mac OS Snow Leopard 10.7, Objective C, Xcode 4.5.2, iOS SDK 5.0+ Implementing Yidio application for iPhone. Yidio is the platform for the discovery, consumption, and socialization around entertainment and digital media. Blackberry 10 support for Titanium Studio Windows 7, QNX QDE, v8 JavaScript engine, BB Cascades Porting the Titanium Mobile SDK codebase to BB10. CorelDraw X6 version maintenance Windows 7, VS 2010 Development and maintenance. FAA NAS Voice Switch Linux Fedora 14 with QT 4.7 Implementing SIP extension based on SIP stack from Media5. Cisco Umi telepresence extension for mobiles MacOS 10.6, Java, iOS SDK 3.2+ Implementing Cisco Umi telepresence extension for iPhone/iPad. Flip Share Project on Android and BlackBerry devices Windows XP, Java, Eclipse IDE 3.4.2, Android SDK 1.5, BlackBerry JDE Video streaming. Web client UI design and implementation for Android and BlackBerry devices. Human resource time-tracking system extension Windows XP, C#, WCF/WPF, VS2008, SQL Server 2005, SVN Team lead of 3 resources. Design and development of desktop extension of existing web-based time-tracking system. ChoiceStream, Web Recommendation Manager Windows XP, Linux, Aptana Studio, Ruby on Rails, JavaScript, RSpec, Selenium, Tomcat, Mongrel, MySQL, Perforce Secured website development, test automation. Handling technical design issues. Nortel PC Client AS5300 Services Project Federal Project containing base Nortel PC Client, including new features for federal purposes. Nortel PC Client maintenance Windows, MS VS2003 PC-based application: telephone service, video calling, instant messaging, real-time call disposition, conferencing, file sharing and white boarding. Personal Projects iPhone application development Mac OS Snow Leopard 10.6, Objective C, iOS SDK 3.1 Streaming video client UI design and implementation, based on web services providing by customer. Alarm Clock for iPad Mac OS Snow Leopard 10.6, Objective C, iOS SDK 3.2+ http://itunes.apple.com/us/app/alarm-clock-with-flashlights/id413649717 http://itunes.apple.com/us/app/cool-alarm-clock-day-reminder/id504174371 http://itunes.apple.com/us/app/alarm-clock-day-reminder/id547232326 Compass application for iPhone, iPad devices Mac OS Snow Leopard 10.6, Objective C, iOS SDK 4.3+ http://itunes.apple.com/us/app/compass-pro/id458958949 Speedometer application for iPhone, iPad devices Mac OS Snow Leopard 10.6, Objective C, iOS SDK 4.3+ http://itunes.apple.com/us/app/speedometer-s54-speed-limit/id483710281 Zombie Detector (Smart Camera) Mac OS Snow Leopard 10.6, Objective C, iOS SDK 4.3+ https://itunes.apple.com/us/app/zombie-detector-smart-camera/id552760128

    Associated with: ARARAT

    $16.67 /hr
    155 hours
    4.87
  7. Victor Cernobai

    Victor Cernobai Agency Contractor

    Senior C++ Financial/Trading Software Developer

    Romania - Tests: 2 - Portfolio: 2

    Hello and welcome to my oDesk profile, My name is Victor Cernobai and I am a professional C++ developer exclusively specialized in developing trading (and related) applications. I am in the financial industry since 2009. During this time I have participated in the development of a wide range of modules involving concepts such as high frequency trading, client/server architecture, distributed modules, OOP design patterns, low-latency optimizations, multi-threading, GPU acceleration, IPC, Socket Programming etc. My main IT expertise is C++, but I also do have working experience with Python and C#. Some more details about my expertise: a) API connectivity: Interactive Brokers API, Currenex API, FIX protocol with QuickFIX, IQFeed API, Trading Techologies, CQG, PFGBest, FXCMpro, Hotspot/ITCH, Bloomberg Open API; b) Building financial charts: OHLC, bars, Point and Figure; c) Implementing technical indicators like: Moving Average simple/exponential, MACD, RSI, bollinger bands etc. d) Data storage solutions: MySQL, SQLite, MSSQL, binary files; e) Back-testing and Optimization solutions; f) Trading algorithms: arbitrage algos, mean reversal, trend-following, trendline based etc.; As a freelancer I am only struggling to: a) Apply my programming and trading knowledge to bring higher value to trading applications; b) Be always close to the client; c) Take projects only when 100% confident they can be done on time and on budget; d) Provide the best answers to clients questions; e) Work only with serious clients. Thank you for your time and do not hesitate to ask me for portfolio samples! Best regards, CVI

    Associated with: CVI Trading Software Agency

    $55.56 /hr
    1,065 hours
    4.88
  8. 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
  9. Denis Danilevskiy

    Denis Danilevskiy Agency Contractor

    Windows | Mac OS | Qt | C++ | .Net Developer

    Russia - Tests: 2 - Portfolio: 3

    Over the past 8 years, I have developed various applications for the web, desktop computers, industrial devices. I like to solve interesting problems and bring work to the end to my design and make a profit to the customer. Platforms: Mac OS X, Windows XP - 8.1, Windows Embedded, Windows CE, Linux Language: Qt/C++, QML. C#, .NET, ASP.NET MVC, ASM, Silverlight for Windows CE, WPF Technology: RS-232/485, Bluetooth, RF, RFID, USB, DSP, CAN, Modbus, GPS, GLONASS, GSM / GPRS

    Associated with: nan.soft

    $20.00 /hr
    53 hours
    5.00
  10. 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