The people who sign every mandate.

Louis founded Casti Energy & Services to answer a gap he had watched widen for a decade: the distance between international technical standards and the operating realities of West African upstream projects. The firm's early mandates — independent reservoir reviews, local content strategy and collateral oversight — grew directly out of that observation.

Before Casti, Louis spent over fifteen years inside the energy sector, combining roles with international service majors and regional operators. The experience shaped a conviction that technical rigour and regulatory fluency are not opposed — they are the same discipline, practiced from two angles.

Today he leads Casti Ghana's advisory practice, maintains the firm's institutional relationships with the Petroleum Commission and the EPA, and personally signs off on every technical deliverable that leaves the Accra office.

Louis is a frequent contributor to regional energy dialogues on local content, independent verification and the commercial realities of West African upstream development.

Mahamar founded Casti UK in London to give the group a principal presence in one of the world's deepest petroleum markets. The desk was designed from day one to trade physical cargoes — not purely paper — with a strict focus on West African supply and a disciplined approach to trade-finance and counterparty risk.

He leads the firm's supply relationships with Atlantic-basin refiners, its vessel chartering programme and its commercial negotiations with importing utilities and retail operators. In parallel, he directs Casti UK's logistics advisory practice, where the desk's operational experience is turned into consulting work for state-owned importers and large cargo lifters.

Mahamar works closely with his counterpart in Accra to make sure Casti's two branches behave as one firm — technical opinion in Ghana reinforces commercial opinion in London, and vice versa. That coordination is the group's principal competitive edge.

He represents the firm in European trade-finance forums, vessel chartering associations and the broader dialogue around fuel supply security for West Africa.