Built by engineers. Driven by purpose.
Sieben was built by engineers who believed the industry could do better, for clients, for quality, and for Zambia.
our story
We didn't just want to build structures. We wanted to build something meaningful.
Sieben was founded by seven friends who met in high school and studied engineering together at university. When the time came to decide what to do with our qualifications, we made a choice that felt bigger than any individual career: to build something together.
We believed, and still believe, that engineers have the potential to make a real difference. Not just in the structures they design, but in the experience they create for the people who commission those structures. Too many clients in Zambia had been let down by contractors who overpromised, underdelivered, and went quiet when things got difficult. We wanted to be different.
So in 2021, seven engineers founded Sieben, named for the German word for seven, and for the seven of us who started it. Our commitment from day one was simple: treat every client’s project with the same seriousness we would want applied to our own. Communicate clearly. Manage money responsibly. Deliver what we promised.
Over five years and more than twenty projects later, that commitment has not changed. What has changed is the depth of our team, the range of our experience, and the trust our clients place in us, including clients who build from thousands of kilometres away, relying entirely on our word and our work.
THE TEAM
Our experts
Every project at Sieben is overseen by qualified engineers. This is the team behind your build.
CO-FOUNDERS
Bornwell Siakanomba
Civil Engineer
Bornwell holds a Bachelor of Engineering in Civil and Environmental Engineering from the University of Zambia and a Master’s Degree in Engineering from Gifu University in Japan. Currently serving as Chairperson of the Civil and Structural Engineering Section of the Engineering Institution of Zambia, he brings over 13 years of post-qualification experience overseeing major infrastructure projects across Zambia — including road and bridge works for the Road Development Agency and district infrastructure for the Ministry of Local Government. At Sieben, Bornwell brings that same rigour to every build: ensuring projects meet engineering specifications, quality standards, and budget commitments from foundation to finish.
Gabriel Mubuyaeta
Civil Engineer
Gabriel holds a Bachelor of Engineering in Civil and Environmental Engineering from the University of Zambia and is currently completing a Master of Engineering in Construction Management. A certified Project Management Professional (PMP), he brings over 10 years of experience spanning structural design, infrastructure development, and project management — including World Bank-funded projects with the Road Transport and Safety Agency and Lusaka Water and Sewerage Company. At Sieben, Gabriel applies that depth of technical expertise to ensure every project is designed, supervised, and delivered to the highest engineering standards.
Kakompe Lutangu
Mechanical Engineer
Kakompe holds a Bachelor of Engineering in Mechanical Engineering from the University of Zambia and an MBA from the Copperbelt University. Over a career spanning more than 13 years with Davis & Shirtliff — one of Africa’s leading water and energy solutions providers — he has managed branch operations across Lusaka, Livingstone, and the Copperbelt, overseeing teams, client relationships, and technical delivery at scale. At Sieben, Kakompe brings his engineering background and operational leadership to ensure projects are resourced, managed, and executed efficiently from start to finish.
Mukolo Sikazwe
Supply Chain and Logistics
Mukolo holds a Bachelor of Engineering in Mechanical Engineering from the University of Zambia, an MSc in Supply Chain and Sustainability Management from the University of Strathclyde — where he studied as a UK Government Chevening Scholar — and has completed supply chain programmes at MIT and the University of Cape Town. A certified MCIPS professional, he has spent over a decade managing complex logistics and procurement operations for multinational organisations including LafargeHolcim and Chilanga Cement, and currently serves as Procurement Management Head at Zanaco. At Sieben, Mukolo ensures that materials are sourced responsibly, costs are managed transparently, and supply chains never become the reason a project falls behind.
Frank Mangena
Construction Manager
Frank holds a Bachelor of Engineering in Civil Engineering from the University of Zambia and a Master of Science in Project Management from the University of Lusaka. A registered Professional Engineer with both the Engineering Institution of Zambia and the Engineering Registration Board, he has over a decade of hands-on experience managing infrastructure projects across Zambia — from road rehabilitation and water supply systems to major public works including the Lusaka Decongestion Project. At Sieben, Frank is the person on the ground ensuring that what was agreed on paper is built to specification, on schedule, and to the standard every client deserves.
Caesar Samwaka
Maintenance Engineer
Caesar holds a Bachelor of Engineering in Mechanical Engineering from the University of Zambia and an MBA from the University of Lusaka, and is a certified Project Management Professional (PMP). With over 10 years of experience in equipment maintenance, maintenance management systems, and capital project delivery — including senior roles at Chilanga Cement and Zambia Sugar — he brings a level of technical rigour and systems thinking that few contractors can match. At Sieben, Caesar ensures that every build is maintained to the highest standard throughout the construction process, and that the finished product is handed over in the condition it was promised.
Mwaba Kamala
Geomatic Engineer
Mwaba held a Bachelor of Engineering in Geomatic Engineering from the University of Zambia, where he graduated top of his class and was awarded the Mikalile Trading Prize for academic excellence. A registered Professional Engineer with both the Engineering Institution of Zambia and the Engineering Registration Board, he brought over a decade of precision surveying and spatial engineering experience to Sieben — gained across Konkola Copper Mines, the Ministry of Lands, and infrastructure projects across Zambia. His technical rigour, his commitment to doing things properly, and his belief in what Sieben could become were foundational to everything the company is today. Mwaba passed away on 18 December 2024. He is deeply missed by his co-founders and remembered in every project Sieben delivers.
SUPPORTING TEAM
Choolwe Chileshe
Sales and Administration
Choolwe holds a Bachelor of Science in Economics with Development Studies from the University of Zambia, where she also served as Chairperson of the Research Committee for the UNZA Business and Economics Association. With a background spanning client-facing roles, financial services at Prudential Life Assurance, and administrative experience at a legal firm, she brings a strong combination of organisational ability and people skills to the Sieben team. At Sieben, Choolwe is often the first point of contact for prospective clients — ensuring every enquiry is handled promptly, professionally, and with the warmth the company is known for.
Penelope Lialabi
Sales and Marketing Intern
Penelope holds a Bachelor of Science in Biological Sciences from Mulungushi University and brings a strong foundation in administrative coordination, client engagement, and sales support. Before joining Sieben, she gained experience across guest services, personal assistance, and environmental education — roles that sharpened her organisational skills and her ability to manage multiple priorities with care. At Sieben, Penelope supports the sales and administration team, ensuring that client enquiries are tracked, documentation is in order, and the day-to-day operation runs smoothly.
Mwewa Kasongo
Civil Engineering Intern
Mwewa holds a Bachelor of Engineering in Civil and Environmental Engineering with Credit from the University of Zambia, where she was an EIZ scholarship recipient and served as Secretary General of the UNZA EIZ Student Chapter. She brings hands-on experience in site supervision, technical reporting, and construction documentation gained through internships at the Lusaka City Council Engineering Services Department and Vertu Construction. At Sieben, Mwewa supports the engineering team across site supervision, project documentation, and BOQ preparation — bringing fresh technical knowledge and a genuine commitment to quality workmanship.
WHAT DRIVES US
Transparency
Our clients always know what is happening, where their money is going, and what comes next. We communicate proactively, not reactively.
Quality
Every project at Sieben is overseen by qualified engineers and architects. We do not cut corners on materials, workmanship, or process.
Partnership
We work with our clients, not just for them. Their vision drives every decision we make, and we solve problems together rather than unilaterally.
Accountability
We own the outcome from the first conversation to the final handover. If something is not right, we make it right.
TRUSTED BY
Trusted Sieben with their projects.
