Technical Co-founder & Lead Engineer
Tooma
Blockchain-powered marketplace and payment infrastructure for digital creators in Kenya, Ghana, and Nigeria—USDC on Stellar with automatic conversion to local mobile money.
Nairobi · Kenya, Ghana, Nigeria creator payments
The problem
African digital creators lacked end-to-end infrastructure to monetise internationally. Processors blocked African accounts or charged fees that killed micropayments. Creators juggled separate wallets, KYC portals, conversion tools, and file delivery—workflows that broke at every handoff. No processor natively bridged M-Pesa / MTN MoMo to USDC on a permissionless network with automated escrow for digital goods.
The client need
Production payment infrastructure: local mobile-money checkout → USDC escrow → smart-contract release → local offramp—plus KYC compliance gated against transaction routes.
What I built
As software engineer and technical lead, I owned architecture, backend, blockchain integration, and technical documentation—translating co-founder requirements into a shippable product spanning web, mobile, payment service, and S3 delivery.
Blockchain payment pipeline
- Buyers pay local currency via Flutterwave mobile money → USDC to Stellar escrow → Soroban contract verifies and triggers offramp → local currency to creator mobile money
- Soroban smart contracts hold USDC, verify receipt, and conditionally release funds
- Payment service for Stellar wallets, Flutterwave orchestration, contract invocation, and PostgreSQL transaction state—Lean work cut payment downtime by 15%
Compliance & platform architecture
- Smile Identity KYC—document validation and facial recognition with approved / pending / rejected gates on all transaction routes
- Full stack: Next.js web, React Native mobile, API Gateway, Payment Service, Metadata Service, AWS S3 file delivery
- C4 diagrams for team alignment and investor documentation
Impact
27 early adopters · $5,500 Stellar Foundation grant · 15% reduction in payment processing downtime · live USDC-to-fiat remittance across Kenya, Ghana, and Nigeria. Though Tooma did not reach market fit, it left working blockchain payment infrastructure and a proven USDC-to-mobile-money playbook for African fintech and creator economy projects.
Tech stack
- Next.js
- React Native
- PostgreSQL
- Stellar (Soroban)
- Flutterwave
- KotaniPay
- Smile Identity
- AWS S3
- TypeScript
- DigitalOcean
More selected work