Top Upwork Freelancers

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  1. Asif Gohar

    Asif Gohar

    System, Network, Active Directory, Exchange, Backupexec, System Center

    Bahrain - Last active: 1 month ago - Tests: 5 - Portfolio: 5

    Knowledgeable and skilled IT professional with encompassing work experience spanning more than 8 years in systems administration with compliance as per industry standards. Possess excellent interpersonal skills to liaise amicably with diverse groups of people, different departments, vendors and agencies. With extensive exposure to different cultures and work environments and has worked effectively with multinational individuals and professionals from all organizational levels. Certifications: MCITP (Server 2008, Exchange 2010, Lync 2010) Expertise: Exchange 2007/2010, Active Directory 2003/2008, SCCM, SCOM, DPM, SCVMM, BackupExec,Enterprise Vault, WSUS, Lync, Server 2003/2008, ADRMS, SQL Server, SAN/NAS.

    Groups: Microsoft Certified Professionals

    $20.00 /hr
    270 hours
    4.95
  2. Joshua C.

    Joshua C.

    Security-focused IT Admin & Developer

    United States - Last active: 1 day ago - Tests: 1

    I worked as senior software developer for a high-tech security corporation for 2 years (and still do consulting with them) and have been a developer for 6 years. I was responsible for their security audits and testing of their SaaS apps. I developed many cryptography-focused applications and wrote dozens of integration projects for cryptographic hardware tokens. I'm familiar, and up to date, with modern hash schemes (ie. SHA2, MD5), symmetric/block algorithms (ie. AES), and asymmetric algorithms (ie. RSA) and best practices. I practice secure programming in all of my projects and always follow best practices to ensure the final result is of the highest quality. I'm well-versed in PHP, HTML5, CSS, JavaScript (including jQuery, Angular, and Node), Bootstrap, PhoneGap / Cordova, WordPress, and ASP.NET. I also run a security-focused blog (https://joscor.com) and provide security audits for large state agencies in the area.

    $60.00 /hr
    62 hours
    5.00
  3. Vitali H.

    Vitali H.

    Software Architect / Developer, Java/J2EE, Android, Web

    Belarus - Last active: 1 month ago - Tests: 1

    Wide experience in software engineering. Languages: - Java (Spring, EJB, Jersey, Atmosphere, Hibernate, OpenJPA, JMS, OAuth, Morphia, Web Services (SOAP, REST), Android, GWT, JSF/JSP, Swing, etc), - HTML, CSS, XML, Javascript (jQuery, Prototype, etc), Databases: MySQL, PostgreSQL Oracle, MongoDB; SEO & User behavior tracking: Google Analytics, Yandex Metrika OS: Ubuntu, Debian, CentOS, Windows; Web servers: Apache, Nginx, Tomcat, Glassfish, Jetty; Other services & tools: SVN, Git, Red5, JasperReports, Maven, JProfiler, Zabbix, Sonar;

    $20.00 /hr
    22 hours
    5.00
  4. Thomas Weidman

    Thomas Weidman

    Developer (PHP, ColdFusion, C#, .NET, MVC3, HTML5, jQuery, Sitefinity)

    United States - Last active: 2 days ago - Tests: 3

    Since 1998, I have done a wide range of web development and have used many technologies (C++, Perl, VB, VB.NET, C#, ASP, ASP.NET, ASP.NET MVC2, ASP.NET MVC3, SQL, PL SQL, T-SQL, ColdFusion [CFML], PHP, ActionScript). I have also used many tools from Flash, Fireworks, Photoshop, Dreamweaver, Eclipse, and Visual Studio. My core skill set lies in problem solving and creating solutions to solve problems in the most efficient (time, budget, and quality) way. I enjoy development and do so in my free time. I use that time to explore new topics that look interesting and to expand my knowledge on existing topics. I have a unique work experience and understand not only coding but also network and server implementations (being a system administrator). I have experience integrating technologies to fulfill requirements or solve limitations of technologies. An example of this I can provide is a solution I did for a client. The solution involved ColdFusion, SQL Server 2005, and ASP.NET Web Services. Due to specific security requirements and limitations of interoperability of ColdFusion 7 and ASP.NET I developed SQL Server CLR Functions and Procedures that invoke web services and return structured data to ColdFusion. From a CF developer perspective all you do is call a stored procedure or execute a cfquery call. The DBMS server does the rest and because it has the ability to use the .NET language I was able to invoke custom services that had very specific security requirements. This solution has been in place for three years now and has not had any issues with this method. I have also used different technologies to handle things like encryption for PCI compliance. I worked with a client to build a custom transactional processing system that utilized C++, Java, SQL Server, PHP, and ColdFusion. The end result is a distributed secure system that handles all payment processing for this client (Web and Internal). This solution also required an understanding of Firewalls, IDS, and how to combine technologies so they would work together seamlessly. If you're looking for a developer who can research options, architect solutions, develop and document, I am an excellent choice and look forward to working with you.

    $66.67 /hr
    294 hours
    5.00
  5. Geza Akocsi

    Geza Akocsi

    Windows system and network administration, web development

    Hungary - Last active: 5 days ago - Tests: 4 - Portfolio: 1

    In the last 3 years I'm working as consultant, developer and system administrator in introduction of document management projects based on ELO system. (<a href="<a href="http://www.odesk.com/leaving_odesk.php?ref=http%3A%2F%2Fwww.elo.com"";;;; target="_blank">http://www.odesk.com/leaving_odesk.php?ref=http%3A%2F%2Fwww.elo.com"</a>;;;;; title="You are about to go to a URL outside odesk.com"><a href="http://www.odesk.com/leaving_odesk.php?ref=http%3A%2F%2Fwww.elo.com";;;; title="You are about to go to a URL outside odesk.com">http://www.elo.com</a></a>)I have 15 years of experience in system management in small business area. (Windows based servers and workstations, network planning and management.)In last five years I have designed and developed some websites from scratch, including areas of e-commerce and web-based business management.I have a lot of practice in remote management and it is my new tendency in my support field.

    $11.11 /hr
    17 hours
    4.81
  6. Hannan Azam Khan

    Hannan Azam Khan

    Expert .NET, Orchard, SharePoint and Office 365 Developer

    Pakistan - Last active: 7 days ago - Tests: 4

    I have over 8 years of experience in analysis, design, development and implementation of portals and web applications. My main areas of expertise are Microsoft Sharepoint and .NET Web Application development. I have experience of multiple migration and maintenance projects involving Sharepoint, Orchard CMS, Umbraco, Kentico, Sitefinity and Apps for Sharepoint Office 365. The web application solutions i worked on involved complete branding of web sites using top notch technologies and frameworks such as HTML5, Bootstrap, Foundation etc to make them fully responsive for all desktop and mobile devices.

    $15.00 /hr
    42 hours
    5.00
  7. Varuzhan Sargsyan

    Varuzhan Sargsyan

    C/C++/VC++, C#, Android Java

    Armenia - Last active: 1 month ago - Tests: 4 - Portfolio: 4

    Over 5 year I was freelancer and have developed the Android applications. Made few apps which are on Google Play now and which are very perspective projects. And more then one year, I'm working as Senior Android developer in company. Look into my portfolio to find the project links I have freelancer experience working on C# windows forms, WCF, MS SQL Server. Project Internal Audit System with 10.000 clients. Project is working nowdays beginning from 2011. Duration of working period takes more then 2 year. Biginning from 1997, I developed in 3-4 companies and have experience in c/c++ programming language, using all Visual Studio versions. I made a lot of programs for a few companies and a production. Using strong knowledge, experince, my programs made companies work more easy and automated. Also I can speak English, Russian, Armenian, and the draft software for production was made using Russian language(menus, messages and all other tools).

    $20.00 /hr
    73 hours
    5.00
  8. Ievgen Gorovyi

    Ievgen Gorovyi

    PhD,image and signal processing expert

    Ukraine - Last active: 12 days ago - Portfolio: 5

    I'm working in field of signal and image processing. My relevant skills include various signal processing and analysis techniques, computer vision and machine learning, artificial intelligence and pattern recognition and many more. My main instruments include but are not limited to: - C/C++/C# - OpenCV - Matlab,R I have successfully received a PhD in Physics and Mathematics and I am actively involved in scientific research. Currently, I have more than 25 publications and dozen of reports at international conferences all over the world. My aim is to provide a high-quality solutions of problems of different scale and complexity. I'm always interested in new work and open for the discussion. I have successfully built one of the strongest profiles in Freelancer and created a team of enthusiasts, who are working with me.

    $44.44 /hr
    332 hours
    4.77
  9. John Comeau

    John Comeau

    expert troubleshooter, generalist developer, tenacious problem solver

    United States - Last active: 8 days ago - Tests: 2 - Portfolio: 1

    "Jack of all trades, master of none" is typically said in a derogatory fashion, but I adopt the title gladly, and you will not likely find more than a few dozen generalists worldwide who can match my troubleshooting and problem-solving skills. I've been programming, on and off, for 40 years, if you count my study of BASIC in 1968, 6 years before I actually got my hands on a computer: the DECSystem-10 at Worcester Polytechnic Institute. As a result of working on computers and microcontrollers of various sizes and capabilities over the years, I have learned to get to the basics of a problem, come up with a prototype solution, and refine it to the customer's satisfaction. My methodology, which I found later is used by many successful programmers, is "build one to throw away"... once the code is working, rewrite it from scratch, correcting the false assumptions made in the first attempt, and refactoring to make a clean, maintainable, codebase. My background in both the electrical/electronics side of things plus years of experience reverse-engineering and improving software on dozens of different architectures gives me the rounded background necessary to take on projects which leave specialists lost. I may charge more than most ($100 is my usual rate, but I found it's unrealistic on Odesk), but when you've run up against a brick wall, I can likely find a way over, around, or through it.

    $100.00 /hr
    87 hours
    5.00
  10. Christopher Brower

    Christopher Brower

    Senior Network Architect

    United States - Last active: 9 days ago - Tests: 2

    • Active Directory Implementation and Administration • Application and OS Automated Deployment • Database Administrator – Microsoft SQL Server 2000 and 2005 • Desktop Engineer – Automation of OS And Application Deployment • Help Desk Support • Group Policy and User Policy Administration • IIS Administration 5, 6, & 7 • Phone Engineer – Designed and Implemented 80 Phone VOIP PBX System • Physical and Logics Network Infrastructure Design • Physical Security Design and Implementation – IP Camera and IP Access Control • Network Security Design and Implementation • Messaging Administrator – Microsoft Exchange Server 2003 • Technical Documentation and Training • Vendor Relations & Purchasing • Virtualization Engineer – Microsoft Virtual Server and VMware ESX Server • Web Services Administrator • Wireless Network Infrastructure Design and Implementation • Adware / Malware / Spyware / Virus Removal • Architect Solutions for Customer’s Needs • Digital Achieving and Electronic Records Management • Disaster Recovery • Email Administration • Hardware Diagnostic and Repairs • Helpdesk Services • Network Diagnostics & Installations • Network Wiring • Server Installations and Provisioning • Server Maintenance • Software Installations • Software Patching and Upgrades • Phone System Installation and Support • Physical Network Repairs

    $66.67 /hr
    105 hours
    4.50