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Fintech Systems Architect / Payments SpecialistNairobi, EAT (UTC+3)

High-throughput payment engines & automated ledgers.

Safaricom M-Pesa Daraja API integrations (C2B, B2B, B2C, STK Push), Redis + BullMQ webhook workers, and automated double-entry ledger sweeps.

Safaricom M-Pesa Daraja (C2B, B2B, B2C, STK Push, Query APIs)Redis + BullMQ high-throughput webhook ingestion queuesReal-time utility-to-working account automated sweepsImmutable double-entry ledger & reconciliation enginesStripe and Paystack global multi-currency checkout railsAutomated dunning state machines & SMS payment notices
The payments ledger: every rail's transactions reconciled into one view.Drag to spin · click to inspect · 1/4
Idempotency
100%
zero double-charges
Webhook Latency
<85ms
immediate 200 OK ACK
Settlement Rate
99.98%
automated reconciliation
Missed TXNs
0
persistent queue retries
01

Packaged Fintech Solutions

Zero-downtime payment gateways, automated zero-balance sweeps, and custom subscription billing engines.

Package 013 to 4 business days

Zero-Downtime Payment Gateway Integration

Bulletproof M-Pesa Daraja, Paystack, and Stripe payment pipelines.

  • M-Pesa STK push, C2B validation, and confirmation endpoints
  • BullMQ asynchronous webhook queue processing
  • Cryptographic signature verification & idempotency guards
  • Real-time transaction status queries & auto-reversal handling
Integrate Payments
Package 023 to 5 business days

Automated Revenue Settlement & Sweeps

Scheduled zero-balance utility sweeps and automated payouts.

  • B2B and B2C automated settlement workflows
  • Threshold-based automatic sweeps to main accounts
  • Double-entry bookkeeping transaction logging
  • Audit trail reports & automated PDF statement generator
Setup Auto-Sweeps
Package 034 to 7 business days

Custom Billing & Subscription Engine

End-to-end recurring subscriptions, dunning & automated invoicing.

  • Custom recurring billing cycles & grace period timers
  • Automated dunning state machine (SMS/Email retries)
  • PDF invoice generation & automated dispatch
  • Customer payment history & receipt lookup portal
Build Billing Engine
02

Battle-Tested Case Studies

Real webhook ingestion workers, BullMQ queues, and double-entry transaction ledgers.

Case Study 01Production Outcome

High-Volume M-Pesa Daraja Webhook Queue & Dunning Engine

The Bottleneck

Synchronous payment webhooks dropping under concurrent traffic, leading to uncredited customer accounts and manual reconciliations.

The Architecture

Engineered an asynchronous gateway that returns immediate 200 OK acknowledgments to Safaricom while pushing payloads into Redis BullMQ workers with exponential backoff and PostgreSQL transaction locks.

The Business Impact

100% transaction capture under burst loads, zero uncredited payments, and sub-100ms processing.

Read the full project breakdown
Case Study 02Production Outcome

Automated Multi-Account Revenue Sweeps & Double-Entry Ledger

The Bottleneck

Funds getting trapped in utility accounts, requiring daily manual portal logins to transfer to operational accounts.

The Architecture

Implemented scheduled B2B M-Pesa sweep workers integrated with double-entry accounting ledgers that track balances and execute zero-balance sweeps upon reaching threshold amounts.

The Business Impact

Zero manual transfers, automated daily ledger audit logs, and instantaneous reconciliation.

Read the full project breakdown
Immediate Action

Ready to solve the bottleneck?

Engage directly for technical audits, turn-key integrations, or high-leverage infrastructure retainers.

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