Meet the Team

Founder

David Cole

David Cole - Architect, Lead Developer

  • Level 3 Technical Support
  • Assembler Coder
  • Product Designer

Dave has owned and operated ColeSoft since 1988. He is the lead developer of the company's core product, the source level assembler debugger z/XDC, which first came to market as the "DeBugging Controller (DBC)" in 1980.

Dave has 40 years of programming experience in z/OS, MVS, and predecessor systems, and has earned a reputation as an authority in his field. ColeSoft serves as an informal clearing house for z/OS "lore", and z/XDC users often call upon Dave not to discuss z/XDC, but to ask about z/OS itself. Dave's understanding of z/OS internals has been greatly enhanced through his network of software engineers in z/XDC's user community, which has helped enhance the features of z/XDC and contribute to the dissemination of knowledge on z/OS internals.

Dave's poetic article, "The Comfort of Perfect Logic", talks about how programming feels to him.

You can hear Dave discuss his career and the creation of z/XDC with Paul Newton of IBM on the z/Action! podcast here.

You can write to Dave at This email address is being protected from spambots. You need JavaScript enabled to view it.

Sales & Support

Bob Shimizu

Bob Shimizu – Sales, Product Educator

  • Level 1 Support
  • Sales and Renewal Support
  • Product Training

Bob was the first person in the door after Dave founded ColeSoft, and he has been handling customer relationships since 1988. He directs sales and renewal support, first level technical support, product training, and product evaluations. He authored the z/XDC Primer and the z/XDC Quick Reference books, and has done ad work and several websites for ColeSoft over the years. If you have a question about z/XDC, he'll be happy to help you or find someone who can.

Bob lives in Prescott, AZ. He is taking Grandfather Lessons from four little kids. Bob is also a nationally recognized jazz guitarist. If you are interested in that side of Bob's enterprises, please check out BobShimizu.com.

Read Bob's article about the relevance of the mainframe industry, "Mainframes are IT!".

You can write to Bob at This email address is being protected from spambots. You need JavaScript enabled to view it., or call him at (800) XDC-5150.

Technical Team

Frank Chu

Frank Chu – Development Programmer

  • Level 2 Technical Support
  • System Programmer
  • Problem Analysis
  • Quality Assurance

Frank is a development programmer and one-man IT department. He provides second level technical support to our customers, investigating and trouble shooting technical issues, bug fixes, and providing a large portion of the quality control for ColeSoft's products. Frank also writes a lot of z/XDC's internal maintenance.

Frank is an excellent cook, which earns him the title of "ColeSoft Executive Chef". He lives with his family in Charlottesville, Virginia.

You can write to Frank at This email address is being protected from spambots. You need JavaScript enabled to view it., or call him at (540) 456-6164.

Michael Lewis

Michael Lewis – Development Programmer

  • New Feature Developer
  • Feature Programmer

Michael is a second generation mainframer who literally grew up playing on raised floor. He taught himself various computer languages, including IBM assembler language.

Over the next 30 years, Michael worked for the EPA Office of Enforcement and for the IRS, as well as several private sector companies such as IBM, EDS, and Software AG. In that time, Michael designed and authored three commercial software packages that "made it out the door" – a patented IBM facility known as DNET, and ColeSoft's own tfs/XDC and cs-cdf/XDC.

In his spare time, Michael plays piano, collects things, and spends time with his wife and family in Sanford, North Carolina.

You can write to Michael at This email address is being protected from spambots. You need JavaScript enabled to view it..

Peter Morrison

Peter Morrison – Development Programmer

  • New Feature Developer
  • Feature Programmer

Peter Morrison has been in the IBM mainframe industry for over 40 years, over 26 of those as an architect/developer with the NetMaster product.

In that time he has designed many applications, and has implemented many of those designs.

He has been an enthusiastic user of XDC since 1990, and now has been able to apply his skills and experience with XDC towards further development.

You can write to Peter at This email address is being protected from spambots. You need JavaScript enabled to view it..

Administrative Team

Calin Cole

Calin Cole – President

  • Operations
  • Customer Contracts
  • Administration

Calin formally joined the ColeSoft team in 2013, although he's been a participating member his entire life. He handles the business management side of ColeSoft. He answers the big questions and helps Tamara with larger administrative items. He also deals with the details of customer contracts.

Calin enjoys building furniture, woodworking, and helping raise his children. He lives in Charlottesville, Virginia with his wife, Media Developer Becca Cole, and their daughters Sophie and Madeline.

You can write to Calin at This email address is being protected from spambots. You need JavaScript enabled to view it., or call him at (540) 456-8851.

Tamara Critzer

Tamara Critzer – Comptroller

  • Human Resources
  • Administration
  • Office Management

Tamara works behind the scenes making sure ColeSoft pays all the bills and follows all the tax laws. She also handles HR for the company. She and Wendie team up to keep everyone else in line.

In her spare time, Tamara enjoys horseback riding, cross stitching, antiquing, swimming, and spending time with her family, two grandsons and a granddaughter. Tamara lives in Nelson County, Virginia, with her husband and family.

You can write to Tamara at This email address is being protected from spambots. You need JavaScript enabled to view it., or call her at (540) 456-6921.

Wendie Wyant

Wendie Wyant – Senior Bookkeeper

  • Customer Support
  • Administrative Support

Wendie provides customer support on the administrative side. She handles product packages, documentation requests, zap requests, and invoice questions. She and Tamara make sure the office runs smoothly.

Wendie lives in Afton, Virginia, with her husband Mark, their girls, Amanda and Crystal, and their granddaughter, Oakleigh.

You can write to Wendie at This email address is being protected from spambots. You need JavaScript enabled to view it., or call her at (540) 456-8210.

Becca Cole

Becca Cole – Media Developer

  • Media Creation
  • Website Maintenance

Becca handles website and social media maintenance, and is responsible for producing marketing, education, and technical materials.

Becca joined the ColeSoft family in 2015, after joining the Cole family when she married Calin in 2011. She is an avid gardener and reader, and collects books. Her hobbies have fallen by the wayside now that Sophie and Madeline take up most of her free time.

You can write to Becca at This email address is being protected from spambots. You need JavaScript enabled to view it..