Our Team

Darrell Letterman, President


Darrell was raised in Fairfield, CA. He has been married to his wife Cindy for over 30 years. They have raised 7 children in Fairfield.  Fairfield is still home for Darrell and Cindy.  Darrell has been in construction for over 40 years. Starting out as a laborer in high school, he has learned many trades from his experiences working for both large and small construction companies.  He became the new owner of Keller Engineering in 2010 and incorporated in 2013.  Darrell loves to work in his hometown community.

Jonathan Cantrell, Concrete Specialist and Project Foreman


Jonathan has over 35 years of construction experience.  Jonathan and Darrell have known each other since grade school and have worked on numerous projects together throughout the years.  Jonathan specializes in the design and set up of concrete projects.  He also heads up the concrete pours and finishing.

Jose Esquibel, Sealcoat Specialist and  Project Foreman

Jose has been working in the asphalt and sealcoat business for 30 years.   He specializes in the application of sealcoat and striping.  Jose is meticulous and treats every project as if it was his own personal property.

Ramon Cobos, Striping Specialist


Ramon has been working in the asphalt and sealcoat business for 30 years.   He also specializes in the application of sealcoat and striping.  Ramon is our striping expert.  He can make every striping project look amazing with his ability to always make straight and crisp lines.