I am a professional full stack software developer and business intelligence specialist with extensive experience in .Net technologies, web applications, APIs, and data migration. With an engineering background and Professional Engineer designation in Ontario, I specialize in creating efficient, scalable software and BI solutions that help companies modernize legacy systems and improve data-driven decision-making. Over the years, I have worked with diverse clients in real estate, healthcare, insurance, and financial services, focusing on ETL, database design, application development, and reporting. I enjoy using tools like Azure, Power BI, C#, and SQL Server to deliver solutions that solve complex business problems and enhance operational workflows.

David S. Kalman

I am a professional full stack software developer and business intelligence specialist with extensive experience in .Net technologies, web applications, APIs, and data migration. With an engineering background and Professional Engineer designation in Ontario, I specialize in creating efficient, scalable software and BI solutions that help companies modernize legacy systems and improve data-driven decision-making. Over the years, I have worked with diverse clients in real estate, healthcare, insurance, and financial services, focusing on ETL, database design, application development, and reporting. I enjoy using tools like Azure, Power BI, C#, and SQL Server to deliver solutions that solve complex business problems and enhance operational workflows.

Available to hire

I am a professional full stack software developer and business intelligence specialist with extensive experience in .Net technologies, web applications, APIs, and data migration. With an engineering background and Professional Engineer designation in Ontario, I specialize in creating efficient, scalable software and BI solutions that help companies modernize legacy systems and improve data-driven decision-making.

Over the years, I have worked with diverse clients in real estate, healthcare, insurance, and financial services, focusing on ETL, database design, application development, and reporting. I enjoy using tools like Azure, Power BI, C#, and SQL Server to deliver solutions that solve complex business problems and enhance operational workflows.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
See more

Language

English
Fluent

Work Experience

Full Stack Web Development and BI at Adaptor Analytix (Self Corporation)
December 21, 2020 - Present
• Created C# web applications in .Net Core, Angular, Node.js for a real-estate business; administered the applications in Azure; this was an upgrade from the MS Access system the company used before. • Administered code versions in Git; tested offline development in Docker; performed unit testing; CI/CD deployment with Azure DevOps • Migrated data from legacy Access DB to SQL Server with SSIS; created reports in Power BI. • Creating Excel dashboards with array formulas, Python and VBA for clients in recruiting and real-estate industries, providing customers with quick tools for startups and investors to get KPI’s. • Joined a small software production company to support their legacy staffing product and to release a novel rental management product
Financial Analytics and Software Developer (Contract) at AVENIR ENERGY INC.
October 13, 2024 - June 12, 2025
• Established MS Access and MS SQL Server cash balance models to reconcile tens of thousands of monthly payments amounting to $30M/month. • Produced ETL mechanisms for loading revenue data into databases with CDATA Arc. • Created reports for cash flow, revenue and operational forecasting in Excel and Power BI. • Produced cash reconciliation tools with Excel, VBA and Power Query; programmed algorithms that find multiple payments that add up to deposits. • Created month-end cash reconciliation processes for the bank and NetSuite ledgers – for payables and receivables. • Managed CRM enhancement and bug remediation – created business requirement documents (BRD’s) and tested changes for production.
Application Developer (Contract) at Nova Healthcare Administrators
June 18, 2023 - July 11, 2024
Brought Nova Healthcare up to date with 2020’s era .Net applications enabling them to abandon their fallible and expensive Access databases: • Converted old MS Access/VBA legacy ETL processes and 6 reports into automated SSIS processes and scripts, SSRS reports. Created SQL scripts and stored procedures. • Created a C# Razor Web application to replace an Access application, coded with HTML, CSS, JavaScript, jQuery; deployed to QA/Production with Internet Information Services (IIS). • Converted an old MS Access process into two .Net WinForms and two SSRS reports. • Decoded complex business rules and conducted QA using Power Query in Excel.
Application Developer (Contract) at Humana
June 21, 2022 - June 14, 2023
Joined a team of two offshore API and SQL developers to be the lead on-shore developer for the maintenance of Humana’s “Sharehub” – a data-mart that provides data via REST and SOAP .Net API’s. Enabled this trillion-dollar insurance company to provide clinical data to all its primary systems. • Supported, debugged and administered 13 C# API’s with 49 endpoints, together with SSIS ETL processes, in Sharehub. Used Postman, Swagger and SOAP UI to troubleshoot API’s. Used Qlik Attunity for data replication. Used Dollar Universe to schedule SSIS processes. • Worked with Git code repositories and CI/CD pipelines in Azure DevOps, which included SonarQube and unit testing (code coverage). • Wrote C# unit tests for a new .Net Core Windows service. • Created C# applications to tabulate SSIS control flows in Excel. Created a utility to convert stored procedures to be compatible with Snowflake. Decoded XML files that define complex SSIS packages. • Worked in a SAFe (Scaled Agile Framework) cadence; used ServiceNow to administer code changes.
Software Developer and Data Engineer at McKesson
June 9, 2019 - June 20, 2022
Joined a team of five developers to support McKesson’s unstable drug Patient Support System that it inherited from a recent acquisition. Kept the lucrative PSP business running while also taking the initiative to solely manage four data migration projects for external pharma clients. • Conducted ETL of drug programs from McKesson systems using MS SQL Server T-SQL scripts, SSIS processes and C# utilities; liaised with clients and was the subject matter expert for PSP data. • Maintained, remediated and enhanced the PSP MS Access/VBA/MS SQL Server application with a team of developers in a DevOps project using Jira to administer development and code reviews. • Supported and enhanced C# utilities, Windows services, WinForms and REST API's. Added Web displays with ASP MVC, C#, HTML, CSS and JavaScript. Used Postman for troubleshooting API’s. Migrated API’s from Jira on-prem to Jira Cloud.
Software Developer (Contract) at London Life
October 1, 2018 - May 30, 2019
• Worked solo to retrofit an existing MS Access networked CRM into a SQL Server based system, while maintaining the native Access/VBA front end forms. • This job required a complete overhaul of the legacy VBA code and the conversion of the Access tables and queries into SQL Server tables, views, stored procedures, functions and user types. There were also opportunities to replace existing processes with more efficient algorithms. • This system performed much better than the legacy system and improved the user experience.
Report Developer (Contract) at MCAP Financial
April 14, 2018 - September 26, 2018
• Was the second developer in a team of two developers, two business analysts, a QA technician, reporting to the director of commercial mortgages. • Worked in an Agile project collaborating with Visual Studio Team Services (VSTS). Replaced half the legacy data warehouse reports for the new reporting system. The new reports were developed with T-SQL stored procedures and SSRS. Also assisted the QA technician with Excel based QA tools.
Manager, Planning Analytics at Sears
March 3, 2013 - December 30, 2017
• Was the primary resource within the Planning & Replenishment for dozens of inventory, replenishment and merchandise planning reports and tools, which informed executive decision-making and guided staff processing for stocking 120 stores, a catalogue and an e-commerce business. • Created and maintained data warehouses in MS Access and SQL Server. Loaded and transformed data (ETL) with SSIS, Alteryx or VBA. Created reports in Tableau and Excel. Created applications for users (tools) in Excel and VBA.
Program and Data at Ontario Ministry of the Environment
March 8, 2004 - March 1, 2013
• Worked for 9 years on multiple reporting projects to implement the 121 recommendations in the Report of the Walkerton Inquiry (2002). Began this mission by founding the Drinking Water Division’s business intelligence (BI) systems and establishing ETL processes in MS Access, Excel and VBA. • Created dozens of databases, data warehouses and applications for drinking water metrics and financials for administration. Used MS Access, Excel, VBA, Cognos and ArcGIS. • Established permanent artifacts that are reported on annually in the Chief Drinking Water Inspector’s report, many are still in use in 2025 – some examples: - Ontario’s risk scores for drinking water systems - Interactive maps of drinking water systems on Google Earth - Conventions for accounting for distinct drinking water systems and the population of residents that consume municipal drinking water

Education

BACHELOR OF APPLIED SCIENCES, Engineering Science at University of Toronto
January 11, 2030 - August 28, 2025
MASTER OF ENGINEERING at University of Toronto
January 11, 2030 - August 28, 2025
Certificate in Database & Knowledge Management at Toronto Metropolitan University
January 1, 2007 - June 30, 2010

Qualifications

Professional Engineer - Professional Engineers Ontario
January 1, 2010 - January 1, 2030

Industry Experience

Healthcare, Financial Services, Government, Retail, Software & Internet, Real Estate & Construction, Energy & Utilities

Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
See more

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