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Writing

Notes on systems that have to stay correct.

September 2026 ยท 9 min read

Two balances and a log

Notes on the ledger I designed for CredPal, a Nigerian consumer credit platform serving hundreds of thousands of users. Almost every hard problem in it lived in the gap between the money a customer had spent and the money the provider had actually moved.

Ledgers

Payments

Distributed systems

Fintech