Dan Kozlowski, Developer in Arlington Heights, IL, United States
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Dan Kozlowski

Verified Expert  in Engineering

Web Development Developer

Arlington Heights, IL, United States
Toptal Member Since
June 18, 2020

Dan has been an expert in the technology field for 25 years and has collaborated with several large firms, such as Oracle and Accenture, including startups. He also had the chance to develop his own business. His latest technology focus has been on eCommerce, full-stack web development, and Elasticsearch. Dan had many opportunities to architect and deliver large-scale solutions to clients while staying hands-on with the technology throughout his career.


Google Analytics, Database Design, Google Cloud, Amazon Aurora...
USA Pool Pros
Google Analytics, Google Cloud, Software Development, Bitbucket, eCommerce...
Database Design, IT Business Analysis, Business Analysis...




Preferred Environment

Databases, REST, JavaScript, Web Technologies, Web Development, Next.js

The most amazing...

...project I've created is a recent React search application that incorporated NLP, ML, and Elasticsearch, to deliver superb search results to research analysts.

Work Experience

Technical Architect | Developer | CTO

2009 - 2021
  • Increased eCommerce conversion rates by 50+ percent and increased sales by 30 percent by migrating the store from Magento 2 to BigCommerce.
  • Led offshore and onshore teams through several lifecycle projects, developing custom Magento and BigCommerce experiences.
  • Architected several enterprise solutions in Google Cloud and AWS through successful lifecycle deployments. The solution supports Magento, Oracle WebCenter, and other software packages.
  • Integrated WebCenter sites and WebCenter content for ADM. Migrated existing website data to Oracle.
  • Integrated the full lifecycle release of a Magento 2 store with Oracle EBS for Rogers and Hollands Jewelry.
  • Worked on an entire lifecycle of Magento 2 deployment and customization for Moon Audio. Started in Magento 2.2.1 and managed through 2.3.1.
  • Built and integrated the Magento warranty module for a startup that incorporates Node.js and a React back-end application via REST and synced and integrated it to Magento and NetSuite order fulfillment.
  • Replaced a Documentum-based KB for Medicare and Medicaid with Oracle WebCenter Portal and Oracle WebCenter Content.
  • Grew the client web traffic by 30% over one year by optimizing SEO and page speed performance through Google Lighthouse.
  • Oversaw all consulting engagements over ten years.
Technologies: Google Analytics, Database Design, Google Cloud, Amazon Aurora, IT Business Analysis, Business Analysis, Business Process Analysis, ETL, Data Migration, Software Development, GraphQL, Bitbucket, eCommerce, Data Engineering, Data Analysis, Debugging, React, PL/SQL, MySQL, Git, Oracle RDBMS, Oracle WebCenter Content, Freelancing, Web Development, Redis, Linux, eCommerce Platforms, Varnish, REST APIs, Test-driven Development (TDD), Magento 2, Google Cloud Platform (GCP), Amazon Web Services (AWS), Oracle WebCenter Sites, JavaScript, Magento, Oracle WebCenter Portal, JavaScript 5, Elastic, Elasticsearch, ELK (Elastic Stack), Kibana, Next.js, Data Analytics, Relational Database Design, Looker, Magento Community Edition, Oracle, Oracle SQL, Dashboards, API Integration, CSS, Data Management, Cloud, Key Performance Indicators (KPIs), Data

CTO | Co-owner

2009 - 2012
USA Pool Pros
  • Owned and operated an eCommerce business that grew from $0 to $1 million/yr revenue in just three years.
  • Increased AOV by 20% with Magento 1 technology initiatives including the creation of a unique bundling module that allowed the sale of entire pool packages, this increased average AOV, and margins.
  • Managed company development and customer service operations.
Technologies: Google Analytics, Google Cloud, Software Development, Bitbucket, eCommerce, Data Analysis, Debugging, MySQL, Google Cloud Platform (GCP), Git, Oracle RDBMS, Web Development, Redis, Linux, eCommerce Platforms, JavaScript, REST, SOAP, Magento, JavaScript 5, Relational Database Design, Magento Community Edition, API Integration, CSS, Data Management, Cloud, Key Performance Indicators (KPIs), Data

Technical Architect

2006 - 2009
  • Served as the lead architect to integrate Oracle solutions with Oracle WebCenter. Technologies included OAM, Oracle ATG, Oracle EBS, Oracle BPEL, Oracle PBM.
  • Interfaced with stakeholders and senior-level management to design solutions to meet customer objectives, while staying within budget.
  • Architected and designed solutions for budgets ranging from $100,000 to $2 million.
  • Trained and mentored consultants on new initiatives.
  • Provided leadership for five-member project team delivery of 1.5 million in services work.
  • Orchestrated, designed, and presented software solutions to customers during scoping and design phases.
Technologies: Database Design, IT Business Analysis, Business Analysis, Business Process Analysis, ETL, Data Migration, REST APIs, Data Engineering, Data Analysis, Debugging, PL/SQL, Java EE, Oracle RDBMS, Oracle WebCenter Content, Web Development, Linux, SQL, JavaScript, HTML, Java, Oracle WebCenter Portal, Data Analytics, Relational Database Design, Oracle, Dashboards, API Integration, CSS, Data Management, Cloud, Key Performance Indicators (KPIs), Data

Technical Architect

2002 - 2006
  • Provided pre-and post-sales support to the scope and deliver professional services for deployment of company software.
  • Coordinated and deployed technology to hundreds of thousands of endpoints through client desktop support and help desk teams at major companies.
  • Selected to visit troubled accounts or high-value prospects to secure new business or retain existing clients.
  • Directed enterprise team, managed schedule, delegated assignments to consultants, and partnered with customers to define enterprise work.
Technologies: IT Business Analysis, Business Analysis, Business Process Analysis, Data Migration, Software Development, Data Engineering, Data Analysis, Debugging, Oracle RDBMS, Linux, .NET, Microsoft SQL Server, Visual Basic, Data Analytics, Web Development, Reporting, Dashboards, API Integration, CSS, Data Management, Key Performance Indicators (KPIs), Data


2001 - 2002
Form + Function Consulting
  • Brought on board to sell and implement $1 million Kana CRM project to Columbia House Records.
  • Provided consulting/technical expertise to clients.
  • Headed IT reorganization project process team at ABRN Amro Bank while working to close Columbia House deal.
Technologies: Database Design, IT Business Analysis, Business Analysis, Business Process Analysis, Data Migration, Data Engineering, Debugging, Oracle RDBMS, Microsoft, Data Management, Key Performance Indicators (KPIs), Data


1998 - 2001
  • Tapped to provide process and technical consulting expertise for various initiatives.
  • Aligned with process group and progressed to technical group roles.
  • Led team of five consultants in creation of leading Accenture demonstration used to promote CRM thought leadership to clients.
  • Directed technical delivery of a 30-member team of developers.
  • Trained and mentored junior consultants whose first language was different than mine.
Technologies: Database Design, IT Business Analysis, Business Analysis, Data Migration, LAN, Data Engineering, Debugging, PL/SQL, Java EE, Oracle RDBMS, Microsoft, COM, Data Management, Data

BigCommerce Search App | xsearch.io

Created a Next.js/Node.js/Elastic-based search application to allow the full indexing of BigCommerce product data. It is built to enable the entire year, make, and model automobile fitment and support developer webhooks. The app provides a full-faceted, React-based search UI for the front-end user experience. The project is in beta mode with two companies and is yet to be released commercially.

Major Government Research Lab – React/Elastic Research Tool

As part of a research team, I delivered all the math and science research code into a working web search application. The solution was built using Elasticsearch, Elastic Enterprise Search, Kibana, with a React front end. The solution incorporated many Python-based machine learning and big data solutions that bolted into the elastic application to do topic modeling, NLP classifications, and dynamic topic trend modeling.

Leading Healthcare Provider | Oracle Webcenter Architect

Oracle WebCenter Architect is a Java-based web content management system running on AWS infrastructure to power 30+ websites for a major healthcare provider.
I worked on the application team that managed the infrastructure and took the lead development and architecture roles for the large extended development teams (eight teams in total). I created an innovative static publishing and caching system that used Python to extract HTML data from the Oracle system to speed performance from 2-3 second load times to 300 milliseconds. I also managed automation for patching and upgrades across 100+ AWS servers.

NTWOnline.com Magento to BigCommerce Migration

I migrated a website from Magento 2 and fully integrated it with Mail Order Manager (MOM) to Big Commerce. Also, I used Hawksearch to enable search and search filtering. This increased conversion rates post-launch by 90% and page load time by 40%.

US Cellular

US Cellular needed to replace the dated Documentum-based content management system that powered their intranet and extranet-based agent knowledge portals. Xumulus partnered with the internal IS teams to deliver an innovative solution that leverages Oracle WebCenter sites (OWCS), Oracle WebCenter content (OWCC), and third-party security solutions using both Apache mod_mellon for SAM and Apache mod_auth_kerberos fully integrated to their IAM back end. This allowed external and internal teams to authenticate seamlessly to the new portals. We implemented the Oracle WebCenter sites' 12c platform. The front-end solution was designed to be served off a single OWCS site but used the sites' security context to personalize the site content. Thus, management overhead in creating and managing content across two sites was reduced. Additionally, this allowed for a personalized user experience based on rolls with the organization.

Major Audiophile Website Magento 2 to BigCommerce Migration

I migrated the website from Magento 2 to Bigcommerce while maintaining many custom features from Magento, product attachments, product customizers, and CMS Page customized menus. I also created a new Cornerstone Stencil theme to support the same front end as the Magento store had. Finally, I migrated all products, and page and blog data.

Constellation Brands

Oracle digital asset management system with various modifications. The system was built with Oracle WebCenter content and had several java-based modifications as well as building custom web-based UIs using REST services and jQuery.

Jackson Family Wines

As one of the premier wine families with over 60 brands under its umbrella, Jackson Family Wines needed a solution to allow its channel partners to quickly navigate and find all brand assets housed in its Oracle digital asset management system. They needed a solution that would be easy to implement and to leverage the tens of thousands of assets already in its digital asset management system. By using this system API and by implementing special indexing techniques we were able to create a website that allowed users to find assets using faceted search. Allowing users to quickly hone in on the assets that they were looking for, download them and repurpose them in their marketing and customer-focused activities. TheKey is a huge part of bringing their many brands to market.
1990 - 1994

Bachelor of Science Degree in Chemistry

University of Illinois - Illinois


jQuery, REST APIs, BigCommerce API, Google API, Facebook API, Node.js, React


Elastic, Oracle WebCenter Content, Git, ELK (Elastic Stack), Bitbucket, Google Analytics, Varnish, Jira, Kibana, Logstash, Looker, Akeneo, GitHub, Miva Merchant


JavaScript 5, SQL, JavaScript, HTML5, HTML, PHP, JavaScript 6, PHP 7, Java, CSS, Visual Basic, Python, GraphQL, Python 3


Database Design, ETL, REST, DevOps, Test-driven Development (TDD), Acceptance Test-driven Development (ATDD)


Magento, Google Cloud Platform (GCP), BigCommerce, Magento 2, Magento Community Edition, Windows, Amazon Web Services (AWS), Java EE, Linux, Microsoft, Oracle WebCenter Portal, Oracle, WebCenter


Elasticsearch, Google Cloud, MySQL, Oracle RDBMS, Oracle SQL, Redis, Microsoft SQL Server, Google Cloud SQL, Databases, Amazon Aurora, PL/SQL


.NET, Oracle ADF, Angular, Next.js, Express.js


Web Development, Web Technologies, Oracle WebLogic Application Server, Debugging, Data Visualization, Data Analysis, Data Engineering, Data Migration, Business Process Analysis, Business Analysis, IT Business Analysis, APIs, Oracle WebCenter Sites, eCommerce, Freelancing, Software Development, Data Analytics, Dashboards, API Integration, Data Management, Key Performance Indicators (KPIs), Data, LAN, SOAP, BigCommerce Stencil Design, eCommerce Platforms, Relational Database Design, Cloud, Agile Deployment, Natural Language Processing (NLP), Machine Learning, Chemistry, Google Data Studio, Generative Pre-trained Transformers (GPT), COM, Reporting

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