Our Crew

Mark Little
Company Owner
Born in Sligo Town, Co. Sligo, Ireland, in 1979, Mark’s passion for engineering and construction was evident from a young age. His attention to detail and keen interest in all facets of engineering set the foundation for a successful career in the construction industry. Mark began his hands-on construction experience at just 16 years old, working on job sites while attending trade schools in Sligo and Dublin, Ireland. Coming from a family involved in the construction trades, Mark gained early exposure to the craftsmanship and dedication required to excel in the field.
In 2000, Mark immigrated to Boston to pursue greater opportunities in construction and property development. Starting from the ground up, he worked as a laborer before progressing to become a skilled carpenter and eventually founding his own carpentry company. Over the years, Mark mastered a wide range of trades, including deck building, framing, siding, roofing, kitchen and bathroom remodeling, and custom staircases.
With his wealth of experience and a natural entrepreneurial spirit, Mark co-founded Abacus Construction alongside his Boston mentor and peer, Bobby Mistich. Together, they built a thriving business specializing in general contracting and property development. After Bobby’s passing, Mark rebranded the company to Abacus Builders & General Contractors, honoring their shared vision while expanding its capabilities and reputation.
Today, Mark is at the helm of Abacus Builders, overseeing the company’s construction operations, financial management, and property development ventures. His leadership has propelled the company to become one of Boston’s best general contractors, recognized for its high-quality craftsmanship, clear communication, and commitment to client satisfaction.
Mark’s journey from humble beginnings in Ireland to leading a respected general contracting firm in Boston is a testament to his hard work, dedication, and passion for building. Under his guidance, Abacus Builders continues to grow, delivering exceptional results for clients across Boston and beyond.

Catrina Supple
Office Management and Marketing
Catrina is a cornerstone of Abacus Builders, serving as the Office, Website, and Marketing Manager while taking on a diverse range of additional responsibilities essential to the company’s success. Beyond managing the day-to-day office operations and the content flow of the website, she ensures the company’s internet presence thrives across various platforms, connecting Abacus Builders with a broad audience.
Her multifaceted role includes:
- HR Management: Overseeing all human resources duties, including recruitment, employee relations, and compliance.
- Time Tracking: Managing schedules and ensuring accurate tracking for all team members.
- Material Procurement: Ordering materials and supplies to keep projects running smoothly and on schedule.
- Insurance Management: Coordinating company and project-specific insurance requirements.
- Contract Scrutiny: Reviewing contracts to ensure all terms align with the company’s standards and client expectations.
- Multilingual Communication: Leveraging her language skills to facilitate clear communication with diverse clients and partners.
Additionally, Catrina maintains and organizes customer databases, assists with new client intake, photographs new projects to showcase the team’s craftsmanship, and leads marketing initiatives to promote Abacus Builders across Boston and surrounding areas.
As the wife of company founder Mark, Catrina’s dedication goes beyond professional commitment. Her meticulous attention to detail, organizational skills, and creative vision contribute to the high standards and reputation that have made Abacus Builders one of Boston’s leading general contractors.

Sara Henneberry
Bookkeeper
Sara Henneberry, Mark’s sister, joined the Abacus Builders team in 2023 and now serves as the company’s Head Bookkeeper. A qualified CPA accountant with specialized training in forensic accounting, Sara brings a wealth of expertise to her role. Before joining Abacus Builders, she spent two decades managing financial operations at Abbott Pharmaceuticals, where she gained extensive experience in financial management, compliance, and strategic budgeting.
Sara’s decision to immigrate to the USA with her family was driven by her desire to contribute to the growth of Abacus Builders and be part of the family business. At Abacus, Sara is responsible for managing the accounting needs of both the core company and its LLC sister companies, especially those involved in Ground-Up New Construction projects.
Her key responsibilites include:
- Overseeing the general ledger and ensuring all financial transactions are accurately recorded.
- Managing the accounts payable and receivable process to maintain smooth financial operations.
- Tracking job costs and project budgets to ensure financial accuracy for every build.
- Preparing and maintaining updated tax reports, balance sheets, and annual budgets.
- Producing detailed financial statements to aid in strategic decision-making and ensure compliance.
- Monitoring and analyzing project financial performance to identify efficiencies and improve profitability.
Sara’s meticulous approach and deep financial expertise play a critical role in the continued success of Abacus Builders. Her contributions ensure that the company operates with financial transparency and precision, enabling the team to focus on delivering exceptional results to clients.
As both a trusted family member and a highly skilled professional, Sara exemplifies the commitment to quality and attention to detail that define Abacus Builders as one of Boston’s best contractors.

Ger McGuigan
Supervisor
Ger oversees and directs construction projects from conception to completion. He is offsite to monitor compliance with building and safety regulations. He coordinates and directs construction workers and subcontractors. Another duty of his is to select tools, materials and equipment, and track inventory. He reviews the work progress on a daily basis then plans ahead to prevent problems and resolve any emerging ones. He also Obtains permits and licenses. Overall – Ensures quality construction standards and the use of proper construction techniques.

Ryan
Junior Estimator

Alan Lynch
On Site Foreman

Lua Dossantos
Senior Estimator