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Blockchain Developer

Rockville, Maryland, United States
February 20, 2018

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Tuan Dang–Blockchain Developer

Personal information



Location: 854 College Parkway, Apt T2, Rockville, Maryland 20850

Cell phone: 319-***-****

Summary of Experience

My name is Tuan Dang who is a skilled Senior Developer with over 16 years of experience delivering complex software development projects. I have excellent knowledge of Java/.Net and FullStack technologies including MEAN and Mobile App. I have proven adept at leveraging the latest development methodologies to meet customer requirements. I take a collaborative approach, working with clients on project delivery and making adjustments as needed; and have well-developed skills in requirements management, programming, testing, and deployment. I have strong knowledge and experience with BigData, Blockchain and Cloud Computing (MS Azure/AWS/Micro-services). I have passed the background check to work for US Government as a contractor: Department of Transportation (US DOT), Consumer Product Safety Commission (US CPSC).

Education, Training, and Certifications

Master of Science, Computer Science, Maharishi University of Management, Fairfield, Iowa, USA, 2014-2017.

Bachelor of Science, Computer Engineering, University of Natural Science of HCM City, Ho Chi Minh City, Vietnam, 1996- 1999

Bachelor of Science, Business Administration, Open University of HCM City, Ho Chi Minh City, Vietnam, 1992- 1996

Work Experience

Senior Developer, Freelancer Mar 2017 – Present

HoneyNet Ltd., HCMC, VN

Client: Coop-Mart, HCMC, VN

Programming Skills: Hadoop, HDFS, Sqoop, Hive, Spark, Cassandra.

Coop-Mart is a big retail company which has annual revenue of 2 billion USD. The current Mysql database blows to 15 Gb. The key table has 12 milion records and it grows 20% every year.

Research Hadoop tools to solve the BigData problem and provide solution to migrate from Mysql to Cassandra DB.

Install multi-node HDFS and other tools (Sqoop, Hive, Spark) on AWS cloud.

Design and build a BigData datawarehouse to illustrate the scale-out (not scale-up) architecture: reduce the query time from 2 hours to 12 minutes.

Client: VNU, HCMC, VN

Programming Skills: Hyperledger, Hyperledger Composer, Hyperledger Fabric .

VNU – Vietnam National University is 1 of the largest university in VietNam. This client needs a solution a solve the problem of so many concurrent access to the central database.

I've built an pilot application on Hyperledger Composer and then Hyperledger Fabric to demonstrate the flow for student to view and then register the courses.

Tools to use Hyperledger Composer, Javascript Chain code, Yeoman, Angular.

Apply Identity Management (through Membership Service) to certify participants.

Senior Developer Dec 2016 – Present

DSFederal, Inc., Rockville, MD

Client: Internal, Maryland

Programming Skills: Blockchain, Ethereum, SmartContract, Solidity, Web3.js,TestRPC, ReactJS, React Native, AWS EC2.

Research Blockchain to prepare for company project.

Design a Blockchain-based application and introduce the idea.

Develop a Blockchain application utilized SmartContract.

Build and deploy a Crowd Insurance Fund application using Solidity, Web3.js, ReactJs.

Research Ethereum/ICO to do crowd funding for project.

Apply CA Certicicate to secure the Web server, SSH server.

Client: US CPSC, Maryland

Programming Skills: NodeJs, AWS EC2, AWS Elastic Search, AWS S3, AWS Lamda, MongoLab/MongoDB, Angular 4.

Work onsite in Bethesda, Maryland supporting US CPSC (US Consumer Product Safety Commision) projects.

Design the system using NodeJs, Microservices, AWS cloud and Angular framework.

Implement CI/CD (Continuous Integration/Continuous Deployment) using Visual Studio, TFS.

Develop framework and demo version for the team.

Client: US DOT, Washington DC

Programming Skills: Java, ASP.Net, C#, Solr, MS Azure Portal, Azure App Service, Azure Search Service, Azure Sql Database, Angular 1, Bootstrap, Sql Server, Oracle, VS TFS.

Work onsite in Washington DC supporting US DOT (Department Of Transportation) project.

Develop documentation, including System Design, Admin Manual, User Manual.

Implement CI/CD (Continuous Integration/Continuous Deployment) using Visual Studio, TFS, Azure during development.

Implement US DOT project to migrate the application from Java-based to .Net/Azure based application.

Research some Cryptography algorithms (RSA, SHA) to encrypt/decrypt the sensitive client data (SSN, ITIN).

Senior Developer Sep 2015 – Dec 2016

United Solutions LLC, Rockville, Maryland

Client: Internal project;Rockville, MD

Programming Skills: Blockchain, Ethereum, SmartContract, Solidity, Web3.js, NodeJs, MongoDB, Angular 1, Bootstrap.

Research Blockchain to prepare for company projects.

Build SmartContract for a Lottery application using Soludity.

Deploy lottery application on NodeJs, MongoDB, Angular 1 and Javascript/Bootstrap.

Present the application to the company clients.

Client: Internal project;Rockville, MD

Programming Skills: ASP.NET, JSP, EJB, Angular 1, D3Js, SQL Server, Oracle, MongoDB

Restructured the company’s key product from single object processing to mass volume processing oriented to enhance performance. In most modules, performance was increased by 50% to 200%.

Proposed Object-Oriented design patterns: singleton, interface-based instead of class-based, multi-tier, SOA (service oriented architecture) to apply to core components.

Led and applied d3js to build variety of charts to visualize data: bubble, scatter plots; then generalized them for use in various types of data: connections, hierarchy, rollup.

Research and integrate Google Maps and Bing Maps including search utility to enhance user experience on location-based data.

Migrate the module for displaying contacts/organizations on Google Map from AngularJs to ReactJs.

Maintain important Java web application for MCPS (Montgomery County Public Schools): optimize transaction and loading time from 20 seconds to 5 seconds. This is an educational project which uses Oracle as database, and serves more than 10,000 teachers.

Build modules to serve connections between students and partner/business in MC (Montgomery College) project.

Solution Architect, Senior Developer Feb 2015 - Sep 2015

ZDAAS LLC, Sparrows Point, Maryland

Client: MSDE (Maryland State Department of Education, Maryland)

Programming Skills: Perl, ASP.Net, Jsp, Angular, Bootstrap, MySql

Successfully enhance loading time by replacing heavy server-side ASP.NET grid and DevExpress controls with client JavaScript libraries and Angular framework.

Migrate school management module from Web Form to MVC and Entity framework.

Successfully persuade managers to move source code control from Subversion to Github to utilize the individual commit feature and enable better staging/branching.

Successfully investigated and implemented to port Perl script and Jsp to pure JavaScript including generating Excel output files. Utilized JQuery together with ExcelBuilder library ( to implement the module. The solution was highly praised by managers and client stakeholders.

Identified and successfully lobbied for architectural/organizational enhancements for the project manager to improve productivity. Restructured a huge library in business tier, which used to serve all functional requests into more independent components, which are more flexible and maintainable. The Façade-oriented pattern was replaced with Prototype and Strategy patterns. From this, all changes in functional components can be easily extended without affecting the core abstract component.

Led a team to research JavaScript frameworks to support a mobile, responsive, 2-way binding, single page application. Conducted analysis and chose Angular framework as the key framework (over other options including Knockout, Express, React, etc.) because of its community support, stability, and flexibility.

Applied TDD (Test Driven Development) methodology to approximately 50% of server side functions using VS Test Project.

Senior Developer Jun 2014 – Dec 2014


Client: MUM’s IT Department, Fairfield, Iowa,

Programming Skills: Java, JSP, Spring, MySQL

Overcame persistent obstacles to deliver successful integration of new plug-ins into existing Sakai system to better support system administration, using Java, JSP, JQuery, MySQL, Spring Tool Suite, Bootstrap, and Sitemesh.

Researched options to plug OpenID authentication library to user management module.

Deployed the project on AWS (Amazon EC2).

Business Analyst / Solution Architect Dec 2012– May 2014

DTP ONLINE, Ho Chi Minh City, Vietnam

Client: Internal project.

Programming Skills: ASP.Net, Java, Jsp, PHP, MySQL, SQL Server, Sharepoint

Ensured that all projects were aligned with client requirements.

Conducted targeted analyses to maximize business value of new IT deployments.

Analyzed technology trends to inform final decision in selection of development platform for LMS-Learning Management System product: handheld device-friendly, touch interactive monitors instead of PC.

Lead the team of 10 programmers to implement e-Learning product.

Develop web application in Jsp Spring to manage Sales for company.

Design the infrastructure for the system.

Deployed the system on MS Windows Azure.

Build a plug-in module in C++ running on Linux to detect the DOS attack to the system. The data is stored in a MySQL database and can be exported to an Excel report for later analysis.

Build a script to measure system vulnerability using JMeter. This script inspected the system, making a large number of concurrent requests to simulate DOS attacks. Then performed analysis and developed a solution based on the output report: make the READ/WRITE operations separately.

Delivered highly effective product that resulted in a 30% increase in response time for school, along with streamlining paperwork processes; and recommended separating READ and WRITE operations into independent components. This product is used by more than 12,000 students. It is capable of serving up to 2000 concurrent connections to register courses and resist DDOS attacks.

Aligned software development with customer requirements, making adjustments as needed to accommodate changing customer’s needs. Some customers asked for more than they had proposed at the signing time. Worked with them to clarify scope and, in most cases, demonstrated that their requirements were already met by the deliverables.

Implemented ETL (Extract-Transform-Load) using MS SQL Server Data Tools for VS 2013 to collect students’ data from member school to central database. This was done in a module of EduApps, which is a university management system.

Solution Architect Dec 2010– Nov 2012

STB TECH, Ho Chi Minh City, Vietnam

Client: Sacombank Group

Programming Skills: ASP.Net, C#, SQL Server, Sharepoint

Managed a five-member team building iOffice, which is enterprise collaboration software based on SharePoint.

Conducted research to apply and deploy CRM: MS CRM, vTiger CRM.

Consulted with Board of Directors and composed business plan to establish Software Development Center; and served as Vice Director of the Center.

Solution Architect Oct 2008– Dec 2010

LUXOFT, Ho Chi Minh City, Vietnam / Houston, Texas

Client: Petris

Programming Skills: Jsp, SQL Server

Originated the idea for and then developed a user-friendly and highly interactive module to create operational workflows. The module enables user to drag and drop basic shapes to create a simple or multi-branched diagrams. Then the approval workflows can be generated from these diagrams.

Successfully restructured Petris’s legacy system, helping it to evolve from old technologies to new technical offerings. This involved use of Linq-to-entity (to utilize the sort/search and query collection to replace many iteration) and Generics (to generalize base/parent classes and operations).

Applied NUnit UnitTest to some modules of AFE desktop project in middle layer.

Developed a program to track Internet usage in Local Area Network written in C++/MySQL and run on Linux. This program monitors usage and measures upload/download size through the Internet.

Senior Developer Apr 2007– Sep 2008


Client: Ndex

Programming Skills: Jsp, Asp, SQL Server, Access

Managed a 12- member team to build two key company projects. One of these, CGI was a large effort to create a tool to manage 50,000 members of a religious organization, which required time consumed reports. Restructured the report generator so that it could utilize a variety of report engines like Crystal Reporst, SQL Server Reporting Services, File, etc., without modification. This made the components more flexible, and highly re-useable and maintainable. Without this clear and Object-Oriented architecture, the team would have to modify almost all of the report engines to meet the new added requirement, including the core component.

Apply the FPA – Function Point Analysis to estimate software cost in person-hours. The company used to used Wild Brand Delphi to quote the project.

Senior Developer Apr 2001– Mar 2007

NCS Saigon Corp, Ho Chi Minh City, Vietnam

Clients: CyX, WebMD, CSFactory, E&T

Programming Skills: Jsp, SQL Server, Access

CMC Phase 2. Built a training management system for Renault’s salespeople and mechanics.

FunSMS. This mobile software enables users to send and receive SMS messages with 260 characters instead of the normal 160. In addition, users may type in Vietnamese regardless of the mobile device platform.

Pizza Mobile. Built a phone-based system for customers to order pizza; restaurant owners can also broadcast promotion/sales messages to via SMS.

Pizza Shop. Built a package for pizza restaurant managers; including a POS, POS Admin, and website.

MDIT. Converted a Japanese manufacturing software application from VB6 to ASP.Net.

Uc Chau Polyclinical Department. This software manages Uc Chau Polyclinical Department from reception to patient release and invoice.

Zaimu. Converted a Japanese financial system from VB6 to JS, JSP.

SmartHospital. Total hospital management software system with financial and human resource integration. Supported this project as partner with Vnes company.

MBSG. Website for a Japanese province’s management and natural disaster statistics.

eFlow. Developed a software tool for US credit organizations –TechCU.

Accounting.Net software. Developed an accounting software product for small and medium-scale Vietnamese enterprises specializing in trading and services.

Product Tracker. Support for supervising the worker’s quantity and timesheet in textile company.

Payment module for e-Album project. Built an online payment system that allows clients to pay for goods or services via cash or prepaid card.

Technical Skills

Languages: Java, Jsp, ASP.NET, MVC, C#, VB.NET, C++, Linq, WCF, PHP, VB 6

Web: Ajax, HTML5, JQuery, XML, JavaScript, jQuery, CSS3, Angular.

Databases: SQL Server, Oracle, MySQL, MongoDB, Cassandra

Tools: VS 2012/2015, TFS, Rational Rose, MS Project, MS Office, Crystal Report, Reporting Services, Telerik, DevExpress, SharePoint, SVN, Github, Bootstrap, AngularJS, React, AutoMapper, Solidity, Web3Js, D3Js, ReactJs, React Native, Hadoop HDFS, Hive, Sqoop, Spark, Kafka.

Platforms: Windows, Linux, MS Azure (App Services, Search Services, SqlDB Services), AWS Services (EC2 Virtual Machine, S3 Bucket, Lambda, Elastic Search, SNS).

Software Development Life Cycle (SDLC): RUP, Agile, Scrum, Application Lifecycle Management

Design Patterns: OO (Object Oriented), DDD (Domain Driven Design), SOA (Service Oriented Architecture), Microservices.

Framework: MVC, Spring, MVVM, Unit tests

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