Building for Offline-First in Low-Connectivity Markets
The most demanding engineering constraint in African fintech is not scale. It is the dropped connection. Here is how we design around it.
Brendah Nyirenda
Cashat team
Build a fintech app in a major European market and you can safely assume the network. Build one in rural Zambia and the network is the feature. A user who cannot complete a transaction because they walked behind a building is a user you will lose forever.
The offline-first philosophy
Every Cashat transaction is constructed locally, signed locally, and queued locally. Connectivity is a transport detail, not a precondition. If the network is there, the transaction goes immediately. If it isn't, it goes the moment connectivity returns, with the user already shown a credible local state.
What this required
- Conflict-free replicated data types for the local ledger view
- USSD fallback for the most critical flows
- A reconciliation engine that assumes the client and server will disagree
None of this is glamorous. All of it is the difference between an app that works in a demo and an app that works in a village.
