DEV Community: Stephen Wereko

How I Built an Enterprise Courier Suite with .NET 10 Web API, PostgreSQL, and Tailwind CSS

Stephen Wereko — Mon, 20 Jul 2026 09:27:56 +0000

Building a complete logistics engine isn't just about rendering CRUD forms. Real-world delivery applications require complex state machines, real-time dispatching logic, dynamic fare calculations, and multi-actor security roles.

I recently finished architecting and releasing a production-ready **courier & logistics management system. Here is a technical breakdown of how I structured the architecture, solved the dispatching problem, and decoupled the backend for scale.

🏛️ System Architecture Overview

To ensure high performance and future extensibility (such as plugging in native iOS or Android apps down the road), I separated the core backend completely from the web presentation layer.

Backend: ASP.NET Core (.NET 10) Web API
Frontend: ASP.NET Core MVC consuming the API
Styling: Tailwind CSS + SweetAlert UI event feedback
Database: PostgreSQL (Relational schema with custom indexing) ## ⚙️ Key Technical Challenges & Solutions

1. Dynamic Distance-Based Pricing

Flat fees don't work for logistics startups. Long-distance trips undercharge the driver, while short trips turn away customers.

I implemented a dynamic pricing algorithm inside the API engine that computes the delivery total using standard route parameters:

$$\text{Total Fare} = \text{Base Fee} + (\text{Distance in km} \times \text{Per-km Rate})$$

This allows administrators to adjust regional base fees and per-kilometer rates globally without modifying codebase rules.

2. Automatic Rider Dispatch Engine

Manual dispatching creates massive operational bottlenecks. The system includes an automated assignment dispatcher that runs upon order creation:

Queries the PostgreSQL database for active riders marked as Available.
Evaluates current workload queues.
Automatically attaches the order to the selected rider's active manifest.
Triggers instant updates in the dedicated Rider Portal.

3. Multi-Portal Isolation & Security

The system features 4 dedicated portals:

Admin Portal: Fleet management, rate configurations, global reporting, and user roles.
Client Portal: Order creation, real-time shipment tracking, and delivery history.
Rider Portal: Mobile-first dashboard for active pickups, status updates, and daily run metrics.
Order Management Portal: State machine handling transitions (Pending ➔ Dispatched ➔ In Transit ➔ Delivered / Cancelled).

Security includes token-based authentication and a complete email recovery flow for lost passwords.

🚀 Get the Full Source Code

If you are a developer, freelancer, or startup founder looking to launch a delivery platform without spending 200+ hours coding backend state logic from scratch, the full commercial source code is now live on Codester!

It includes full C# source files, Razor views, Tailwind styling pipelines, and a clean ``PostgreSQL database migration script.

👉 Get the Full Delivery Management System Source Code on Codester

📁 Stop Messy Downloads Forever: Python Organizes Your Files Automatically ✅

Stephen Wereko — Fri, 16 Jan 2026 19:05:07 +0000

If your Downloads folder looks like a war zone 😭 (PDFs + images + zip files everywhere), you’re not alone.

So I built a beginner-friendly Python script that automatically:

✅ Organizes files into folders (PDFs / Images / Docs / Zips / Videos / Sheets)
✅ Creates a folder for today’s date (YYYY-MM-DD)
✅ Renames every file with a timestamp (date/time)
✅ Prevents overwriting duplicates (_1, _2, _3…)

Result: your Downloads folder becomes clean, sorted, and searchable ✅

▶️ Video Tutorial (Silent Coding / No Talking)

I recorded a quick walkthrough showing the before → code → run → after.

📺 Watch it here: https://youtu.be/A3Yz100IbLw

(You can also check my channel: https://www.youtube.com/@CodeGees
)

Downloads/
Images/2026-01-16/2026-01-16_14-20-05_photo.png
PDFs/2026-01-16/2026-01-16_14-20-05_report.pdf
Zips/2026-01-16/2026-01-16_14-20-05_project.zip
import os
from datetime import datetime

✅ Downloads folder

downloads_folder = os.path.join(os.path.expanduser("~"), "Downloads")

✅ Today's date folder

today_date = datetime.now().strftime("%Y-%m-%d")

✅ File categories

file_categories = {
"PDFs": (".pdf",),
"Images": (".png", ".jpg", ".jpeg", ".webp"),
"Docs": (".docx", ".txt"),
"Zips": (".zip", ".rar", ".7z"),
"Videos": (".mp4", ".mov"),
"Sheets": (".xlsx", ".csv"),
}

✅ Loop through downloads

for filename in os.listdir(downloads_folder):
old_path = os.path.join(downloads_folder, filename)

# Skip folders
if os.path.isdir(old_path):
    continue

# Skip shortcuts/temp/system files
if filename.lower().endswith((".lnk", ".tmp", ".ini")):
    continue

# Find file extension
file_ext = os.path.splitext(filename)[1].lower()

# Pick category folder
category_name = next(
    (name for name, exts in file_categories.items() if file_ext in exts),
    "Other"
)

# Create target folder (type + date)
target_folder = os.path.join(downloads_folder, category_name, today_date)
os.makedirs(target_folder, exist_ok=True)

# Create timestamp rename
file_name, ext = os.path.splitext(filename)
timestamp = datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
new_path = os.path.join(target_folder, f"{timestamp}_{file_name}{ext}")

# Avoid overwriting duplicates
counter = 1
while os.path.exists(new_path):
    new_path = os.path.join(target_folder, f"{timestamp}_{file_name}_{counter}{ext}")
    counter += 1

# Rename + move
os.rename(old_path, new_path)

print("✅", filename, "→", category_name)

print("\n🎉 Done! Downloads are now organized by type + date."

✅ Try it Yourself

Save the file as: downloads_folder_organizer.py

Run it:
python downloads_folder_organizer.py

I learned Python in 30 days to save my life. Here is my first script. Tags: #python #beginners #productivity #ghana

Stephen Wereko — Sat, 03 Jan 2026 20:06:16 +0000

In 2019, I lost my job and all my connections. By 2026, I was at my lowest point. I decided to fight back by learning Python in 30 days.

I code on a laptop with broken keys and no microphone, so I record Silent Coding sessions. I am building tools for Accountants, Data Scientists, and Students.

My latest script is a desktop cleaner that organizes hundreds of files in seconds.

Watch the silent build here: [https://www.youtube.com/watch?v=g9x5M90g5Wc&t=119s]

I am proof that you can start again with nothing. Please subscribe to support a dev from Ghana.