Principal Full Stack .net Engineer

Overview

Investec is looking for a Principal Full Stack .NET Engineer / Platform Architect to join the Private Client Lending Technology team in Johannesburg, South Africa, working as part of our UK Offshore Technology function. This is a hands‑on technical leadership role responsible for shaping, developing, and supporting core lending origination platforms and their integrations. The successful candidate will combine strong engineering capability with architectural thinking, ownership, problem‑solving, and the ability to guide other engineers through complex delivery challenges.

You will take ownership of complex technical problems across the full stack—from backend services built in C#, .NET, and Azure cloud services through to modern web frontends—and see them through from analysis to delivery. The role is as much about shaping the right solution as building it: operating comfortably in ambiguity, analysing business and technical challenges, helping to refine requirements, and designing pragmatic approaches that fit the wider lending platform.

Hands‑on engineering remains central, spanning both new solution delivery and the ongoing evolution of existing services.

A core part of the role is establishing and maintaining technical direction. You will produce the solution designs, integration approaches, technical plans, and decision records that help the team understand what is being built, why, and how it fits the broader platform—forming a coherent plan from the input of others and keeping engineers aligned to a clear technical “north star”. You will balance building new solutions with extending and hardening existing systems, ensuring resilience, performance, and regulatory compliance, while working within Agile squads alongside product owners, business analysts, and other engineers.

As part of our UK Offshore Technology function, you will be based in South Africa and aligned to UK teams, collaborating closely with UK‑based stakeholders and engineers across time zones. There are few local peers at this level of seniority, so you will need to be highly self‑sufficient and self‑motivated, comfortable being one of the most senior technical people in the room—someone others lean on for direction rather than someone who needs to be directed.

From the outset you will provide technical and thought leadership through design, review, and mentoring, and over time you are expected to take on broader engineering leadership of the South African team.

• Take ownership of complex problems across the full software development lifecycle— from analysis and architecture through to development, deployment, and ongoing support.
• Engage with stakeholders, business analysts, and product owners to shape ambiguous requirements into clear, well‑architected solution designs.
• Own the design and delivery of core technical building blocks, services, and integrations that enable key lending business processes.
• Remain hands‑on—building, testing, and deploying services and integrations using C#, .NET, and Azure—while setting the technical direction others follow.
• Produce and maintain solution designs, integration approaches, and decision records that give the team clear context on what is built, why, and how it fits the wider platform.
• Take accountability for the technical integrity, quality, and supportability of solutions, including investigating and resolving complex issues in production and test environments.
• Review the work of other engineers, providing constructive critique and clear technical guidance that raises the overall quality and consistency of delivery.
• Help set and uphold engineering standards and best practices, raising the technical bar across the team and ensuring solutions are well‑documented, maintainable, and supportable.
• Mentor and grow other engineers—sharing knowledge, guiding them through complex problems, and building the technical capability of the South African team.
• Provide technical and thought leadership from the outset—setting design direction, communicating a clear technical “north star”, and keeping engineers aligned to a coherent plan shaped from the input of others.
• Collaborate…