Case file 03 · Ops

TRANSMERALDA × COTRANSMEQ

One transport platform adapted to two operators without losing operational identity.

SvelteKit
TypeScript
Fastify
Prisma
PostgreSQL
Expo

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The challenge

Two transport operators shared the same hard problems—fleet, drivers, services, attendance, payroll support and regulatory evidence—but each one carried its own brand, users and operating rules. Copying features between separate products would quickly create drift.

Transmeralda public presentation showing the transport workflow — Public presentation rendered locally; Cotransmeq shares the architecture with its own identity.

Case file 03 · Ops

Driver app screens

Transmeralda driver app

Cotransmeq driver app

The approach

I evolved a shared SvelteKit and Fastify architecture, separating reusable domain workflows from operator configuration and deployment. PostgreSQL and Prisma anchor the model, while an Expo and React Native driver app uses SQLite caches and a synchronization outbox so services, forms and worked days remain usable on the road.

Key decisions

Share the operational core while keeping branding, deployment and operator-specific rules isolated.
Move the driver journey into an Expo app with SQLite caches and an outbox built for intermittent connectivity.
Generate spreadsheets and regulated documents from structured data instead of manual templates.

Technical architecture

Full-stack architecture designed and built end to end by me.

01 Field and office SvelteKit · Expo · React Native
Administrative workspace plus a native driver app for routes, forms and evidence.
02 Operational API Fastify
Shared transport rules isolated from each operator identity.
03 Transport model Prisma · PostgreSQL
Services, fleet, people, safety and compliance records.
04 Operational tools SQLite · Mapbox · Socket.IO · Univer · PDF
Offline outbox, maps, live updates, spreadsheets and regulated documents.

Modules

What the product is made of, as its own screens divide it.

01 Fleet & drivers
Vehicles, drivers, documents and their expiry.
02 Services & settlements
Trips, third-party and service settlements, statements.
03 Payroll & surcharges
Payroll with surcharges computed from the operation itself.
04 Road safety (PESV)
The road-safety plan: checks, forms and evidence.
05 Compliance
SARLAFT, corrective actions and non-conformity exits.
06 Forms & attendance
Custom forms, evidence and token-based attendance in office and field.
07 Driver mobile apps
Two branded Expo apps for services, forms, pay slips and worked days, backed by SQLite and a retryable sync outbox.
08 Two operators, one base
The same codebase branded and deployed for each company.

Before → after

Before
Two products evolving through manual copies.

After
One shared core with isolated operator identity.
Before
Road evidence arriving after the operation.

After
Native offline capture with a durable synchronization outbox.
Before
Manual spreadsheets and document templates.

After
Documents generated from structured operational data.

Technologies

SvelteKit
TypeScript
Fastify
Prisma
PostgreSQL
Expo
React Native
SQLite
Mapbox

The wider toolkit

Zod
Pino
Swagger
JSON Web Tokens
Puppeteer
Univer
Chart.js
ExcelJS
pdfmake
Anthropic
Azure Blob
Amazon S3
Resend
Expo Router
SecureStore
Expo Notifications
Expo Location
Expo Camera
Expo Image Picker
Expo File System
Expo Sharing
NetInfo
Reanimated
Gesture Handler

Brand marks from Simple Icons; concepts without one are drawn in-house.

Project log

Oct 2025 → Oct 2026 · 13 active months

1603 commits

6 repositories

13 active months

Oct 2025 Busiest month: Sep 2026 · 666 commits Oct 2026

transmeralda · app app · 616 commits Oct 2025 → Oct 2026
transmeralda · api API · 288 commits May 2026 → Oct 2026
cotransmeq · app app · 369 commits Feb 2026 → Oct 2026
cotransmeq · api API · 253 commits Feb 2026 → Oct 2026
transmeralda · mobile native · 38 commits Sep 2026 → Oct 2026
cotransmeq · mobile native · 39 commits Sep 2026 → Oct 2026

In the tree

166 routes
108 API controllers
302 data models
135 migrations
163 test files
152 native source files
3370 tracked files

Read from the local Git history on Oct 6, 2026. Aggregates only.

The outcome

The product family expresses one operational model through two web deployments and two branded driver apps. The project log now follows six web, API and mobile codebases; both apps cover services, forms, pay slips and worked days with offline storage and synchronization.

Private codebase — this file shares the thinking, not the source.

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