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Client projectAndroid · Web administrationEngineering case study

Macsim Cargo

Cargo and logistics operations platform spanning mobile field workflows and back-office administration. Macsim handles loads, reservations, driver assignments, trip tracking, documents, notifications, fleet operations and finance, with a guarded M-Pesa/Daraja flow for funding a collection-account ledger and paying drivers in full or partial load installments.

Engineering contribution

Full-stack mobile and operations engineering across cargo workflows, backend services, administration, finance, and guarded M-Pesa driver payouts.

Product scope

A cargo and logistics operations platform covering loads, reservations, driver assignments, trip tracking, documents, notifications, fleet operations, finance, and back-office administration.

Engineering focus

  • Built React Native workflows for load boards, active trips, driver assignments, reservation details, field operations, and location-aware cargo activity.
  • Connected the mobile product to FastAPI/PostgreSQL services and a Next.js back-office workspace for load, fleet, driver, finance, staff, location, and consignee operations.
  • Added a Daraja flow where STK Push funds a tracked collection-account ledger and B2C BusinessPayment sends full or partial load installments to a driver’s Safaricom number.
  • Protected payout accounting with reservations, idempotency keys, callback-state guards, and an immutable ledger debit only after a successful B2C result is confirmed.

Product evidence

Mobile application

Swipe to browse screenshots

Beyond the core product

Supporting systems & extensions

These systems show the additional engineering needed around the product—from internal tooling to automation and operational workflows.

Admin Dashboard

Backoffice dashboard for cargo operations with load-board oversight, active and completed load counts, fleet and driver management, finance access, staff controls, locations, consignees, and quick operational actions.

Admin Dashboard screenshot

Stack

Next.jsReactTypeScriptTailwind CSSPythonFastAPIPostgreSQLFirebase AuthVercel Blob

Code available upon request.

Technology

Core stack

ExpoReact NativeTypeScriptPythonFastAPIPostgreSQLFirebase AuthReact QueryM-Pesa Daraja

Domain & technical context

Industry / domain

LogisticsTransportFleet operationsOperational finance

Expertise demonstrated

React Native & Expo mobile engineeringPython, FastAPI & PostgreSQL backend engineeringREST API, GraphQL & third-party integration engineeringSQL, PostgreSQL, graph & application data engineeringPayment integration, subscription & reconciliation engineeringGitHub, Vercel, Expo EAS & mobile release engineering

Live product & release links

Public product and store links are shown as release evidence. Ratings and review counts are intentionally not displayed unless they are verified from the stores.

Visit product websiteView Macsim Cargo on Google Play

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