I’m Raphael, founder of The Ledger Method
Ventures
Articles
View All ArticlesBreaking the Monolith: Why Microservices Aren’t Always the Hero of the Story
Implementing Domain-Driven Design in a Fast-Paced FinTech Environment
Measuring Air Exchanges: Enhancing Productivity and Reducing Viral Risks in Offices
Publications
View AllUsing AI to Anticipate Healthcare Air Quality Risks
Opinion: New mining by-laws signal a step-up in Zimbabwean resource governance
Sentinel AI rolls out AI dust monitoring across South African mineral belt
AI-Enabled Indoor Air Quality Monitoring- A Comprehensive Trial Test Study
WORK EXPERIENCE
SensusAir
Winner of the Best Environmental Risk Management & Disease Prevention Specialists 2025 – USA and the GHP Innovation Excellence Award 2025, SensusAir is redefining how we understand the air around us. At SensusAir, we believe that air is more than something we breathe; it is an environment, a medium, and a mirror of human activity. It carries particles, gases, pathogens, and invisible signals about the health of our homes, cities, and workplaces, and we have built our platform to make those signals visible, meaningful, and actionable.
I lead the design and development of intelligent sensor systems and data platforms that decode what is truly in the air, with speed, precision, and context. From particulate matter and CO₂ to VOCs, temperature, and humidity, our solutions go beyond simplistic labels like “clean” or “polluted.” By applying the Ledger Method, every measurement is captured as an immutable, contextual entry that contributes to a living record of environmental health. This allows us to deliver real-time insights that reveal not only what is happening, but why it matters, and what can be done to address it.
SensusAir is now trusted by institutions that place people, precision, and prevention at the center of their operations. From school principals making decisions about classroom ventilation to healthcare leaders safeguarding patient outcomes, our mission is to empower organizations to take control of what they cannot see: the air that shapes human wellbeing every day.
Sentinel AI
Built on patented technology (WO2020/250007: DustScout), Sentinel AI is a technology company delivering real-time environmental intelligence for industries operating in high-risk environments, with a strong focus on mining. We believe that dust is not just a by-product of activity, but a critical environmental and occupational risk that carries consequences for worker safety, community health, and regulatory compliance. Sentinel AI makes these risks visible, accountable, and actionable.
I lead the design and development of both the intelligent data platform and the rugged DustScout hardware that powers it. This includes architecting sensor systems capable of surviving harsh mining conditions, and applying the Ledger Method to capture every signal as a contextual, immutable entry. From respirable crystalline silica (RCS) to wheel-generated dust, road conditions, gradient, and thermal surface data, Sentinel AI creates a living ledger of environmental health. This enables operators to see not only the dust load, but also the causes, correlations, and operational levers that can change outcomes.
Sentinel AI is more than monitoring — it is an integrated risk mitigation tool. Our clients use Sentinel to demonstrate ESG compliance, protect worker health, conserve scarce water resources, and improve operational uptime. By replacing outdated, after-the-fact sampling with patented, real-time intelligence, Sentinel AI helps mining companies meet stricter occupational exposure limits while building trust with regulators, investors, and communities.
Mukuru
As the engineering and architecture lead for Mukuru’s Ledger platform, I’ve had the privilege of designing, building, and scaling one of the most critical systems within one of Africa’s largest remittance and financial services companies.
Mukuru operates across 70+ countries in Africa, Europe, and Asia—offering both digital and cash-based financial services. At the heart of this ecosystem lies the Ledger: a highly available, fault-tolerant system that processes millions of transactions and accesses across our platform daily.
I architected the Ledger platform from the ground up, transforming it into a scalable, cloud-resilient system that today underpins all transaction flows across Mukuru’s services. In this role I led distributed engineering teams across multiple countries, driving collaboration, ownership, and continuous delivery in a high-growth, high-availability environment. I implemented modern architectural patterns, moving away from monolithic systems and introducing microservices and event-driven designs to unlock agility and scalability. Alongside this, I evaluated and integrated best-in-class technologies to future-proof our infrastructure, strengthening performance, compliance, and resilience. I also bridged the gap between business and engineering, translating complex financial and regulatory requirements into actionable technical deliverables. Beyond the technology, I played a central role in shaping the engineering culture, mentoring teams, and defining the long-term technical direction of the ledger domain.
GreenModel®
Greenmodel® v4 is a cloud-based financial reporting and analytics platform that enabled real-time, automated compliance and governance reporting for financial institutions. It was built to overcome the long-standing challenges of linking financial data across multiple perspectives, ensuring accuracy, transparency, and speed in reporting processes that were traditionally manual and error-prone.
I led the development of Greenmodel® v4, directing the full engineering lifecycle from coding and integration to testing and deployment. The platform was delivered using .NET, RESTful APIs, JavaScript, and message queuing technologies, with a centralised rules engine, unified datastore, and automated workflows with built-in reconciliation and quality checks. I worked closely with product owners, finance teams, and compliance stakeholders to ensure that every technical decision aligned with business requirements and evolving regulatory standards.
Greenmodel® v4 was recognised internationally for its innovation, winning the **SWIFT Innotribe 2015 (Africa Region)** award for financial services innovation, which included a sponsored presentation at the Sibos Banking Conference in Singapore. This recognition highlighted Greenmodel® as one of the most forward-thinking platforms in automated reporting, bringing fintech-grade rigour to compliance and governance in the financial sector.
