E
Ernest Yoyowah
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Projects & Systems

What I've Built

Production systems, active development, and next-generation tools — across fintech infrastructure and music technology.

FintechProduction

MTN Pay

Central Payment Gateway

MTN Pay is the central payment gateway for MTN, integrated by multiple services including the Self Service Portal. It handles Mobile Money transactions, PCI DSS–compliant Mastercard hosted checkout, and airtime top-up.

PCI DSS–compliant Mastercard hosted checkout
Mobile Money disbursements and collections
Airtime top-up integration
OTP verification and fraud prevention
Resilient flows with retry logic and status polling
ReactTypeScriptNode.jsGolang
TelecomProduction

MTN Self Service Portal

Customer Self-Service Platform

The MTN Self Service Portal (SSP) allows customers to manage and service their MTN accounts independently. It supports broadband, data bundles, SIM management, eSIM provisioning, and more, integrated with MTN Pay for in-portal payments.

Broadband and data bundle management
SIM and eSIM provisioning
Self-service account management
Integrated with MTN Pay for payments
ReactTypeScriptNode.js
TelecomProduction

MTN Pulse

Youth Platform · MyMTN App

MTN Pulse is MTN's youth platform, delivered within the MyMTN app. The platform provides targeted offers, data bundles, and digital experiences for MTN's young subscriber base.

Youth-focused features within the MyMTN app
Targeted offers and data bundle flows
Frontend contribution 2023–2025
ReactTypeScriptNode.js
Identity & SecurityProduction

MTN Auth Services

Centralized Identity & Access

MTN Auth Services provides centralized identity and access control using Auth0, consumed by multiple MTN applications across Ghana and South Africa MTN Group, supporting secure and consistent authentication at scale.

Auth0-based centralized authentication
Consumed by multiple MTN services in Ghana and South Africa
Biometric verification integration with Metrics Africa
Supports centralized access control at scale
Auth0Node.jsTypeScript
SystemsProduction

Autosurveil GPS

Fleet Intelligence Platform

A full-stack fleet intelligence platform providing live GPS tracking, route analytics, and vehicle management. Led the full redevelopment of the platform across frontend and backend.

Led full-stack redevelopment of the platform
OTP-based authentication and onboarding flows
Route history and analytics dashboard
Multi-fleet management interface
Next.jsTypeScriptNode.jsMongoDB
Music TechnologyAvailable

PulseMIDI

MIDI Diagnostics & Monitoring

PulseMIDI is a native macOS application for MIDI signal monitoring, device management, and port routing. Built with Swift and SwiftUI, using CoreMIDI for system-level MIDI access and the CLAP SDK for plugin distribution. Ships as a universal binary targeting Apple Silicon and Intel Macs on macOS 12+.

Native Swift + SwiftUI with direct CoreMIDI framework access
Realtime MIDI signal visualisation and device enumeration
Virtual MIDI port creation and routing
Universal binary — Apple Silicon + Intel, macOS 12+
Standalone, AudioUnit v3, and CLAP plugin distributions
SwiftSwiftUICoreMIDIAudioUnit v3CLAP SDK
Music TechnologyAvailable

PulseControl Bridge

Native macOS DAW Bridge

PulseControl Bridge is a native macOS application that bridges the PulseControl Mobile app to your DAW over a local WebSocket connection. Devices discover each other via Bonjour/mDNS — no configuration required. Creates virtual MIDI output ports via CoreMIDI for seamless DAW integration.

Creates virtual MIDI output ports via CoreMIDI — appears as a real MIDI device in any DAW
WebSocket server receiving MIDI control data from mobile
Bonjour/mDNS network advertisement for zero-config device discovery
Universal binary — Apple Silicon + Intel native
macOS 11+ standalone application
SwiftNetwork.frameworkBonjour/mDNSCoreMIDI
Music TechnologyAndroid Available

PulseControl Mobile

Wireless MIDI Control Surface

PulseControl Mobile turns your phone into a wireless MIDI controller. Android is available now, with iOS coming soon. Touch faders and rotary knobs send MIDI CC data to PulseControl Bridge over a WebSocket connection. Pairing is handled via QR code — no manual network configuration.

Touch faders and rotary knobs transmitting MIDI CC data
WebSocket transport pairing with PulseControl Bridge
QR code pairing — zero manual network configuration
Android available now; iOS release in progress
React NativeWebSocketiOSAndroid