Top Upwork Freelancers

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  1. Dmitry Sytchev

    Dmitry Sytchev

    Asterisk/Freeswitch/Kamalio expert, VoIP engineer, Linux administrator

    Russia - Tests: 7 - Portfolio: 1

    I have more than 10 years of experience in installation and support of carrier-grade VoIP services based on Asterisk, OpenSIPS, Kamailio, Freeswitch and proprietary SIP/VoIP software. My professional interests are Callcenters, automated dialer systems and integration of VoIP software with company information flows. You can rely on my strong engineering and programming skills for projects starting from single VoIP server to a complete wholesale/carrier VoIP solutions including billing, call data analysis, security and fraud prevention. I have developed complete SIP solutions for VoIP carriers worldwide: Proxy/Registrars, IVR, prepaid systems, multi-tenant VoIP switches, hardware PSTN gateways (Cisco AS5300/5500, Audiocodes Mediant 2000, Quintum Tenor). I have experience in setup, administration and security of Asterisk, FreePBX, Elastix and FreeSWITCH PBX installations. As a programmer I use PHP, Javascript (both client-side using jQuery and Angular.js and server-side with node.js), Perl (system scripts/applications, Mojolicious webapps). I also have experience in development and administration of MySQL and Microsoft SQL Server databases. I'm experienced network engineer, skilled in routing and switching, general network architecture planning and deployment, network monitoring and security, including HA solutions (heartbeat/pacemaker). I use Zabbix and have some experience with Nagios and other monitoring software. I can also offer you consulting support in VoIP and network technologies.

    $33.33 /hr
    93 hours
    4.95
  2. Aleksey Bondarev

    Aleksey Bondarev

    Python web developer and analyst

    Italy - Tests: 1

    Some of my Python projects: https://bitbucket.org/Desprit - 'Flask & Django'. Worked as front- and back-end developer; - 'Website crawlers'. Experience in working with Python libraries Selenium, Mechanizer, Scrapy, PhantomJS, BeautifulSoup; - 'Morphological and latent semantic analysis' of texts with NLTK library; Programming experience: - Windows / Linux (Ubuntu); - Python, Flask / Django; - PosgreSQL, SQLAlchemy, SQLite3, MongoDB, RethinkDB; - JS, jQuery, AJAX; - HTML and Haml, CSS and Sass; - Foundation, Bootstrap; - Celery, RabbitMQ; - Heroku & AWS; - Assembla, JIRA, Asana; - Git.

    $17.00 /hr
    96 hours
    5.00
  3. Zhuhriansyah R.

    Zhuhriansyah R.

    Web Technology Programmer

    Indonesia - Tests: 5 - Portfolio: 2

    I'm a professional programmer. Experienced as technical software development leader for +10 years. Excellent at web technology and mobile web platform. I'm a fast learner, hardworking, strong analytical, and good problem solving. I had good educational background and expertise to solve problem with non algorithmic approach, such as artificial intellegence methods, indexing, and others. Experience on Yii, Laravel, HTML5++, Cordova, AngularJS, Ionic, Delphi, Android, iPhone

    $15.00 /hr
    53 hours
    5.00
  4. Michael Ravits

    Michael Ravits

    Full-Stack Software Engineer

    Israel - Tests: 2 - Portfolio: 1

    I am a Full Stack Developer with over 9 years of experience in the industry, working both on Web as well as native applications. While I excel at working with a team, having experienced managing a remote group of developers, I am also capable of single-handedly delivering projects from start to finish. With my skills and experience, I always strive to produce clean, robust and highly tested code for every project. Having a very broad experience with numerous tools/languages and technologies, I specialize in building modern web applications and high-scale data processing pipelines. My language of choice is Clojure. Some of the technologies I've worked with in recent projects: - Server side development on the JVM * Clojure * Cassandra * ElasticSearch * Java * Kafka * Redis * Samza * Spark * Storm - Large and small client side applications in ClojureScript * Om * Reagent * ReactJS As a technology enthusiast I enjoy utilizing these cutting-edge tools to deliver projects quickly and efficiently.

    $79.77 /hr
    858 hours
    5.00
  5. Cuong Le

    Cuong Le

    Senior Software Developer (C/C++/MFC,Java,...)

    Vietnam - Tests: 4 - Portfolio: 4

    Thanks for your reviewing. I am Cuong Le. I have over 6 years of software development experience in C/C++/MFC. Experienced in software development life cycle including requirement analysis, design and implementation. Programming Languages: C/C++, MFC, C#. Databases: PostgreSQL, SQL Server. Software process: CMMI, Agile (Scrum, Jira tool). Other: Visual Studio, Eclipse, UML, GIS, GPS, XML, XML-RPC, COM, Hook, GDI, DirectX (DirectDraw, DirectShow, Direct3D), Touch Screen device and printer device. Further information, please refer at https://vn.linkedin.com/in/ltcuong

    $8.89 /hr
    16 hours
    5.00
  6. Alex Rocon

    Alex Rocon

    Mobile application development

    Bangladesh - Tests: 3 - Portfolio: 7

    I am a mobile application(iphone, android, windows phone) developer. I was doing GIS mobile application development. After that i involved in a product SkyBIZ. Mainly i am a local wireless solution provider that can provide sales man tracking, sales data analyzing, GEO analysis on sales data and some others tools that supports sales department of a business organization. Now i am trying to explore it in the global market.

    $11.11 /hr
    54 hours
    4.60
  7. Md. Robiul Islam

    Md. Robiul Islam

    Appcelarator-titanium | Php | Codeigniter | Wordpress | Joomla

    Bangladesh - Tests: 6 - Portfolio: 15

    Hi, Its always been a pleasure for checking my profile. Since last 2 years, I have developed web Applications using codeigniter, php, mysql and jquery. Now, I have full experience and expertise in delivering high performance web applications. I usually used to make an effort to keep the high quality and exact time frame. My skills are following - Titanium - Android - Angular,Ajax, XML, JSON, Jquery - MySQL, SQLite, HTML5, PHP - Facebook, Twitter, LinkedIn - Google Map Service - Codeignitter, -Opencart - Joomla, Virtuemart, Wordpress, Prestashop Please feel free to contact me any time to discuss your idea. Best Regards, Md Robiul Islam

    $15.00 /hr
    728 hours
    5.00
  8. Daniel Guillermo Bareiro

    Daniel Guillermo Bareiro

    GNU/Linux and Unix system administrator

    Argentina - Tests: 2 - Portfolio: 2

    I manage and use free/open source software and GNU/Linux (most experienced Debian) since 2000. I have also participated in numerous conventions related to these themes (some of them as speaker) and collaborating with the discovery of bugs in applications for contribute with the community. Specialties: Networks and operating systems security, monitoring technologies. Advanced knowledge of GNU/Linux environments and virtualization platforms. LANs, WANs, VPNs, Firewalls, TCP/IP. Description of services: ---------------------------------- Servers: ====== Installations, configurations and maintenance plans for servers running GNU/Linux or free BSD operating systems range. * Planning, installation and configuration of GNU/Linux systems as both free and open source systems. * Installation, configuration and maintenance of servers of BSD range: FreeBSD and OpenBSD. * Print servers. * Mail servers with spam and virus filters. * Proxy servers. * Fax servers. * Corporate instant messaging servers. * Install and configure DNS servers. Procedures for domain management. * Management servers for uninterruptible power supplies. * Web servers (Apache, PHP, MySQL and PostgreSQL). * Database servers (MySQL and PostgreSQL). * DHCP servers. Networks and Infrastructure: ===================== Installation, maintenance and failure analysis of networks. High-availability systems, mass storage, remote backup, and monitoring equipment and services. * Installation and maintenance. * Firewalls. * VPNs. * DMZs. * RAID, SAN and NAS systems. * Implementation of VoIP telephony systems. * Virtualization systems (for production systems, development and testing). * Remote backup systems. * Monitoring systems. * Control, preventive analysis and resolution of faults in networks. * Installing and configuring high availability clusters. Consultancy: ========== My main goal is to provide a work environment based on trust, integrity and transparency, in order to become your strategic partner to help you realize your projects. My experience in the field of free/open source technologies allows me to offer a wide range of consulting services for your business, which include audit and analysis of systems, applications and networks, migration to free and open source systems, and systems integration, among others. * Migrating to free and open source systems. * Network analysis. * Security analysis. * Configuring applications. * Systems integration.

    $36.67 /hr
    55 hours
    4.92
  9. Zulqarnain Mustafa

    Zulqarnain Mustafa

    iOS Developer

    Pakistan - Tests: 2 - Portfolio: 4

    I have been working in field of software development from 4 years. I'm an independent iOS developer with a proven track record of starting new projects and taking them through development all the way to the app store. I've worked as a solo developer and on teams and in addition to development work. During my professional career I have worked on many iOS Applications. My key traits regarding software development are I'm a perfectionist. I pay attention to all the details, and like to be sure that everything is just right. I enjoy solving problems, troubleshooting issues, and coming up with solutions in a timely manner.

    $25.00 /hr
    643 hours
    4.89
  10. Muhammad Imran Afzal

    Muhammad Imran Afzal

    C/C++ Developer,Device Driver,Kernel modules and Bash scripting Expert

    Pakistan - Tests: 4 - Portfolio: 1

    I have 6 years of experience in Linux development and administration. Device Drivers, Kernel Porting, Kernel Modules, Development in networking protocols, gcc/g++ and Python are my expertise. I have strong knowledge in Linux internals including kernel specifics and system calls. I have work experience with mips64 based Cavium's OCTEON multicore netwrok processors. I have worked on network protocol offloading in this. I have the ability TO DO.

    $22.22 /hr
    13 hours
    5.00