Billing, tracking, reports and approvals that run on their own, from a full-stack web developer with 12+ years doing the work by hand inside a national seaport.
Done by hand / email / spreadsheet ? I'll turn it into a system.
What do you need built?
Advance bills, calculated in one place.
Rotation + vehicles → Slabs · VAT · levy → Advance bill
Live · daily use Port Billing System: case study →
One online record everyone can see.
Daily counts → Balances by location → Reports + history
Live · daily use CarView: case study →
Overtime bills, prepared automatically.
Employee + hours → Rate rule → A4 bill
Live · daily use OT Bill Automation: case study →
From idea to a live web app.
Your process → Built and deployed → A link your team opens
Manual work, automated
Each one replaced work that was done by hand at a seaport. The same problems exist in any business that runs on spreadsheets.
#1 · Flagship production system
Billing automation × Rate tables
Agents and importers ask what their bill will be. Revenue staff worked each one out by hand or in Excel.
One calculator applies the port’s wharf rent, VAT and levy rules in a fixed order.
#2 · Operational tracking system
Transport operations × Tracking
Daily vehicle receipts, deliveries and balances lived in one Excel file.
Everyone concerned now sees the same online record for each location, with reports and a change history. It works offline.
#3 · Workflow automation system
Operational administration × Billing
Overtime bills were prepared on paper.
The system prepares them from employee profiles and daily hours, applies the rate rule automatically and prints on A4.
Smaller and newer builds, taken from my GitHub. Each is labelled live or source only. None carries the daily-use status of the three systems above.
A global culinary encyclopedia: dishes by continent and country, with history, occasion and drink pairing.
TypeScript · Cloudflare
Anchora Commerce ↗Source only
Full-stack commerce platform: storefront with cart and checkout, plus a role-gated admin dashboard. A portfolio build, not a live shop.
Next.js 15 · TypeScript · Prisma · PostgreSQL · Docker
AI-drafted outreach for a hand-picked lead list. You review and send each message.
TypeScript · React · Cloudflare Workers AI · D1
SalahSync ↗Live
A prayer-times and daily schedule tracker, used every day.
JavaScript · PWA
A structured English reading course, built content-first.
Next.js · JavaScript
A single-file form that turns a client request into a clear project brief.
HTML · JavaScript
JARVIS ↗Source only
A personal AI assistant with multi-model chat, voice, files and memory.
Python · FastAPI · NixOS
This portfolio ↗Live
The site you are reading: static HTML, CSS and JavaScript on Cloudflare Pages.
HTML · CSS · JavaScript
Professional experience
Hands-on work in billing, reports, tracking, records and teamwork at a national seaport, and how that work became software.
Junior Outdoor Assistant, Port & Terminal Operations
Nov 2013 — Nov 2017Senior Outdoor Assistant, Traffic Department (Revenue Branch)
Nov 2017 — PresentI support port traffic work. This covers cargo, containers, vehicles, billing, reports, records, revenue tasks and working with other parties.
Port operations
Nov 2013 Joined Mongla Port Authority
Daily billing, tallying and reporting done by hand, with the port’s own systems and paper.
Personal and shared spreadsheets for daily figures, then formulas that remove repeated calculation and report steps.
Writing the workflow and rules down before automating any of it.
Small purpose-built calculators, rebuilt as installable web apps other staff can use.
Connected records, roles and reports: billing, tracking and overtime bills.
Using AI tools to build faster, while I own requirements, rules and validation. OpsFlow is the product project.
Present Building operations technology
The software work grew out of daily work problems. Milestones are shown without dates because only the employment period is exact.
How I build
I start with the real workflow, identify where time, data or accuracy is being lost, model the process, and build practical software around it.
Understand the real workflow first. The questions come before any software.
Turn the work problem into a clear software requirement.
Convert the workflow into rules and structures a system can follow. The rules are written down before any code, because software cannot guess them.
Pick the architecture, data model, interface, hosting and tools that fit the need. The tools follow the operation, not the other way round.
Sized to the problem: a calculator that only estimates needs no database, while shared records need a data store and a small API.
AI is an implementation accelerator, not the source of domain knowledge. It speeds up the work once the requirement and the rules are clear.
A system is only useful when it behaves like the process it supports.
In the port billing calculator, the slab, VAT and rounding rules are covered by automated tests and were compared against real bills.
Deploy the working system, watch how it is used, and keep improving it from real feedback.
The live tools run as installable web apps on Cloudflare Pages and Workers, with code versioned on GitHub. Read two real bug fixes, in full ↗
The stages above, applied to two systems in daily use. No real records or figures are shown.
C&F agents, importers and shipping agents kept asking what a bill would be. The port’s billing system makes permanent entries, so they could not check wharf rent before committing, and revenue staff worked each estimate out by hand or in Excel. The result was billing disputes, longer cargo dwell time and repeat trips to the counter.
Check wharf rent and the other charges before submitting, with no permanent entry, and print the bill on A4.
Free time, wharf-rent slabs, VAT and levy, inside and outside storage, and rate changes mid-storage, written down as rules before any code.
Structured forms, saved bills with live search and a dashboard. The rules run as plain JavaScript in the browser, so the estimate appears at once and works offline. Agents still work from paper.
AI-assisted implementation. Requirements, business logic and review stay with me.
The slab, VAT and rounding rules are covered by automated tests and were compared against real bills.
Staff use it at the billing counter to check charges before they submit.
Live · daily use Port Billing case study →
Vehicle positions across warehouse, shed and yard lived in one person’s Excel file. When they were away, the team lost visibility.
Record daily receipts and deliveries for each location, keep a full history, and work offline because terminal connectivity is not guaranteed.
Each location’s closing balance becomes the next day’s opening balance. Receipts, deliveries and transfers adjust it, and a holiday calendar sets the working days.
An installable web app with a Cloudflare Worker. Every save is a version-controlled commit, so any earlier version can be restored. Charts, reports and Excel export are included.
The whole department checks and updates the same record, replacing a single-person file.
Live · daily use CarView case study →
My software work is self-directed and AI-assisted. Its foundation is 12+ years of real operations experience, workflow design, testing and practical system building.
Engineering decisions
Good engineering does not mean the most complex tools. It means the right solution for the real limits.
Decision 1 · Port Billing
Decision 2 · CarView
My engineering principle
Design around the workflow, not around the technology.
I choose technology based on:
Product case study · Building
One connected system for small and mid-sized transport and logistics firms.
From customer orders to trips, invoices, payments and outstanding balances, OpsFlow connects the workflow in one place. Built to help small and mid-sized businesses replace scattered Excel, WhatsApp and manual records.
Implemented: tenant-isolated accounts and roles, customer, route and rate-card data, fleet records and quotations. In development: orders and trips. Planned: invoices, payments, outstanding balances and reports.
Keep the customer data used at every step.
Capture what the customer requested, so operations start from one agreed record.
Show how an order is really carried out.
Turn finished work into a billing record.
Record payment received against business receivables.
Give visibility into unpaid balances.
Turn connected daily data into business facts.
Questions
I am a web developer who builds business systems and internal tools, with 12+ years of operations experience at Mongla Port Authority in Bangladesh. I turn manual work into web systems that teams use every day.
Work a team does by hand, such as spreadsheets, paper forms and hand calculations. I turn it into a web system with the same rules built in.
Three are in daily use: a port billing calculator, a vehicle quantity tracker and an overtime billing tool. More than 8 web applications are live in total.
Yes. The method is the same in any business: map how the work really runs, write the rules down, then build and test the system. Port work taught me billing, tracking and reporting. Other builds on this site are not port work: a content site, a commerce platform, a sales-outreach tool and a course platform. In a new industry I start by learning how your work runs, and I do not claim your domain knowledge.
Yes. I am open to remote work worldwide, including contract projects. Email sa.sumel91@gmail.com to start a conversation.
In local Lighthouse tests on 14 October 2026, ten pages (the homepage, About, Experience, Resume, Capabilities, Engineering, Privacy and three case studies) scored 100/100 for accessibility, best practices and SEO. Homepage desktop performance scored 100/100 and mobile performance on those pages scored 92 to 98.
Contact
If your team runs on spreadsheets, paper or manual steps, in any industry, and you have a process worth automating, I'd be interested in discussing it.
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Elsewhere
Same facts, framed for two kinds of role
