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John R. Kosinski

John R. Kosinski

Chiang Mai, Thailand
Member since October 28, 2015
As a full-stack mobile developer, John has been developing since around 2000. Early on he did some C++, ASP, VB6, and other things, but since .NET came out, most of his work has been in .NET. His work experience up until 2009 was in the NYC and NYC area; since 2009, he's been living and working in Thailand. Currently, he's consulting remotely for US clients and working on iOS, Android, Node.js, and IoT projects.
John is now available for hire
  • JavaScript, 16 years
  • Microsoft SQL Server, 16 years
  • C#, 16 years
  • Agile Software Development, 8 years
  • Scrum, 5 years
  • REST, 4 years
  • Android, 2 years
  • Xamarin, 2 years
Chiang Mai, Thailand
Preferred Environment
Depends on the type of project, I'm flexible.
The most amazing...
...project I've worked on is one that combines augmented reality, neuro-linguistic programming, facial recognition, and machine learning.
  • Alexa Developer
    Anguleris Technologies
    2018 - PRESENT
    • Developed a rich Alexa app that will allow customers to run spoken English queries against a complex product database.
    Technologies: Alexa, AWS, Node.js
  • Senior Node.js Developer
    2017 - PRESENT
    • Developed an automated cash and carry arbitrage trading system for cryptocurrency exchanges.
    • Built a system of three Node.js applications on Heroku and several AWS lambdas over the course of a few months to implement a unique marketing "sell-it-before-implementing-it" system.
    • Created an on-the-fly image generator using Node.js with Gifsicle and WebShot to generate customized promotional "coins" for use on the site.
    Technologies: Node.js
  • R&D Manager
    2017 - PRESENT
    • Developed Alexa Skills for Amazon Dot/Echo.
    • Worked with ESP8266 embedded programming with Arduino IDE.
    • Configured a TLSv1.1 WebSocket security.
    • Developed MQTT communication with AWS IoT cloud.
    • Created a voice-activated smart-home lighting system.
    Technologies: IoT, Alexa, AWS, ESP8266, Embedded C++, Arduino
  • Mobile Developer (Remote)
    2014 - PRESENT
    • Developed a Webby-winning eCommerce iPad application using Xamarin iOS.
    • Added new features on a legacy Objective-C app.
    • Installed new features on a legacy Android app.
    • Consolidated the legacy apps into a new Xamarin unified platform.
    Technologies: Xamarin iOS, Objective-C iOS, Java Android, Xamarin Android, .NET, Selendroid, JIRA, Scrum
  • Alexa Developer
    Sterling VC
    2017 - 2018
    • Developed and brought to market an Alexa skill for retrieving New York sporting news updates.
    Technologies: Alexa, Node.js, AWS
  • Senior Xamarin Developer
    Under NDA (via Toptal)
    2015 - 2017
    • Developed from scratch a Xamarin iOS application that controls large-scale SCADA irrigation systems via a Java middle tier.
    • Built the MVP's architecture and prepared a plan to facilitate cross-platform ports.
    • Created a tight system of synchronizing long-running tasks with the server side, across multiple connections or app sessions.
    Technologies: Xamarin iOS, WebSockets
  • Senior Developer | Team Leader
    Manao Software
    2012 - 2014
    • Managed a team of developers to produce a REST/JSON front-end to a unique SAP-querying interface.
    • Designed the architecture for the above software using .NET Web API MVVM with NHibernate.
    • Managed a team to develop the above software in .NET.
    • Directed the QA unit-testing using SoapUI.
    Technologies: .NET, REST Services, JSON, MVVM, Knockout.js, jQuery, Soap UI, TDD, Scrum, JIRA, Perforce, DDD
  • Software Development Manager
    2009 - 2012
    • Redesigned the rate providers' pulling subsystem.
    • Developed ISAPI filters for the website.
    • Built a prototype mobile/web app.
    • Handled the day-to-day process of development and quality control.
    • Managed a team of 16-to-20 developers.
    Technologies: .NET, C++, JavaScript, SQL Server, PHP, VB.NET, ISAPI, Android
  • Senior Developer
    Morgan Stanley (NYC)
    2007 - 2009
    • Performed the application and web service programming in C# and VB.NET.
    • Interfaced .NET software with legacy COBOL programs.
    • Wrote the GUI design/programming in ASP.NET and JavaScript.
    • Developed software to manage fixed income securities based on currency exchange models.
    • Designed service-based architecture linking .NET applications to core mainframe services.
    Technologies: .NET, C#, VB.NET, JavaScript, COBOL, SOAP Web Services
  • Senior Software Architect
    Braveline Technology (NYC)
    2003 - 2007
    • Developed an internal image server that's still in use and well-regarded.
    • Wrote an eCommerce object-oriented redesign.
    • Developed an internal component library (parts of which are still in use).
    • Serviced clients in various industries including private equity, financial services, entertainment, and accounting.
    Technologies: C#, VB.NET, C++, VB6, SOA
  • Junior Instructor
    SetFocus LLC (NYC)
    2001 - 2003
    • Researched topics to present to students.
    • Assisted the senior instructor in preparing course material.
    • Delivered and and helped to deliver course material to students.
    • Assessed and graded students' work.
    • Became MCT certified.
    Technologies: .NET, SQL Server, COM
  • Languages
    C++, C#, JavaScript, Python, Java, HTML5, Assembly, C, Objective-C, Perl, XML, XPath, COBOL, PHP, N
  • Frameworks
    .NET, ASP, ASP.NET, Sencha Touch, Knockout.js
  • Libraries/APIs
    Node.js, Amazon API, jQuery, WebSockets, MailChimp API, Keras, Mixpanel API, TensorFlow
  • Tools
    Visual Studio, Android Studio, JIRA, Mongoose, Alexa, Xcode, MQTT, AWS SES, SoapUI
  • Paradigms
    Scrum, Model View Viewmodel (MVVM), Agile Software Development, REST, Kanban, Design Patterns, Model View Controller (MVC)
  • Storage
    Microsoft SQL Server, JSON, MySQL, MongoDB, NoSQL
  • Other
    RESTful APIs, Xamarin Forms, SOAP, Trading, Finance, eCommerce, HTTP, Unix Shell Scripting, Internet of Things (IoT), Machine Learning (ML), ESP8266
  • Platforms
    Linux, Web, Xamarin, iOS, Android, AWS IoT, Arduino, Blockchain
  • Bachelor of Science degree in Computer Science
    University of Delaware - Newark, DE, USA
    1993 - 1998
  • PFC USMC in Basic Military Skills
    Parris Island Marine Corps Recruit Depot (MCRD) - Parris Island, SC, USA
    1996 - 1996
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