ERP & business systems
Payroll, HR, attendance, accounting and inventory — modelled on real rules, approvals and audit trails, not demo data.
Requirements & estimation · Schema and workflow design · Role-based access · Production releases & support
Celloscope Ltd. Dhaka, Bangladesh
Atiar Rahman
Full Stack Software Engineer, Angular specialist, ERP & payroll systems, Led a team of 4 engineers
I build the ERP, payroll, HR and accounting systems organisations run on every day — from the requirements meeting to the production release.
- Years exp
- 3+
- Systems
- 10
- On one payroll
- 1,500
- Specializes in
- Full Stack · APIs · ERP · Production
Md. Atiar Rahman
Full Stack Software Engineer
- Reports
- 70+
- Commits
- 4.5k
atiar.ts
const atiar = {
role: 'Full Stack Software Engineer',
company: 'Celloscope Ltd.',
shipped: ['payroll', 'ERP', 'HR'],
stack: ['Angular', 'Node', 'Postgres'],
available: true,
};(01) — Experience
Two careers, one standard.
- Experience
- 3+
- Years shipping enterprise software
- Payroll scale
- 1,500
- Employees paid by a payroll I led
- Reports
- 70+
- Production reports across one ERP
- Commits
- 4,500+
- Commits to production systems
C
Celloscope Ltd.
Dhaka, Bangladesh · On-site
Full Stack Software Engineer Now
Jan 2026 — Present
Junior Software Engineer
Jan 2024 — Dec 2025
Software Engineer Intern
Sep 2023 — Dec 2023
- Angular
- TypeScript
- Hapi.js
- NestJS
- PostgreSQL
- Oracle
- JasperReports
- Docker Swarm
- 01
Deliver ERP features for government and enterprise clients across the whole lifecycle — proposals, requirements, estimation, development, release and user support.
- 02
Led a 4-person team on a university payroll and personnel system and acted as the primary technical contact for the client.
- 03
Ship weekly production releases in a 20-person engineering team; coordinate releases and server hardening with DevOps and write end-user release notes.
- 04
Planned the Angular 14 to 21 upgrade, reworked slow legacy code, built its in-app notification system and own major technical decisions on a modular-monolith Node.js platform.
Before software: civil engineering, 2017 — 2023
Rana Construction and Condominium Ltd · Dhaka, Bangladesh · On-site
Senior Assistant Engineer
Jan 2021 — Aug 2023
Led day-to-day site engineering for building projects, guided junior engineers and reviewed estimates and contractor bills.
Assistant Engineer
Jan 2019 — Dec 2020
Managed construction work on site, prepared estimates and bills, and coordinated contractors, suppliers and site teams.
Sub-Assistant Engineer (Civil)
Sep 2017 — Dec 2018
Prepared AutoCAD drawings and quantity take-offs for residential buildings and supervised work on site.
AutoCAD · Construction Management · Project Management · Construction Estimating
(02) — Case studies
Systems people are paid by.
Payroll, HR, accounting, inventory and retail software I built or led at Celloscope. Client names stay private; the modules and results do not.
University Payroll & Personnel
Salary for 1,500 staff under government pay rules, cut from a week or more to a few hours.
1 week+ → hoursmonthly payroll work
Led a team of 4 engineers
Junior Software Engineer · 2024 — 2026
In production
Pay rulesSalary sheetBank reportQR payslip
- employees paid every month
- 1,500
- payslips open the employee’s data
- QR
- The problem
- Monthly salary under government pay rules took a week or more of work, and allowance and deduction mismatches kept coming back from month to month.
- The result
- Payroll work fell from a week or more to a few hours, and teachers and staff can check their own salary and tax details.
19 modules I worked on
- Salary engine
- Salary sheets
- QR payslips
- Employee portal
- Tax details
- Personnel records
- Provident fund
- Pension
- Accounting
- Increments
- Promotions
- Festival allowance
- Education allowance
- Recreation allowance
- Deduction bills
- Electricity bills
- Approval workflows
- Bank management
- Report suite
Used by: A public university with 1,500 employees
Built with Angular, Hapi.js, PostgreSQL, JasperReports
Shows team leadership, client contact, complex pay rules, reporting
Office Management ERP
One system for accounting, inventory, HR and projects, running in three organisations.
3organisations in production
Technical owner, from intern to today
Intern → Full Stack Software Engineer · 2023 — now
In production · Web, PWA, Android
AccountingInventoryHRProjects
- branches and vendors at one body
- 8 + 5
- reports across the platform
- ~70
- The problem
- One system has to cover accounting, inventory and HR, and attendance has to hold up in the office and outside it, across branches and vendors.
- The result
- Running in three organisations on web, PWA and Android. I reworked slow legacy code to make it faster and easier to use, and planned its move to a current Angular version.
32 modules I worked on
- GPS geofencing
- Attendance
- Leave
- Performance appraisal
- Peer review
- Shift roster
- HR analytics
- Employee portal
- Vendor staff
- Chart of accounts
- Journals
- Financial periods
- Invoices
- Bills
- Payments
- Credit notes
- Vendor credits
- Refunds
- Bank accounts
- Cash book
- Expenses
- Sales orders
- Requisitions
- Allocation
- Warehouses
- Product transfer
- Projects
- Task board
- Timesheets
- Android app
- Slack attendance bot
- Report suite
Used by: Three organisations, including a government body
Built with Angular, NG-ZORRO, Hapi.js, PostgreSQL, Leaflet, Docker Swarm, GitLab CI/CD
Shows long-term ownership, legacy modernisation, performance, web + mobile
Rice Mill Production & Costing
Tracks paddy from purchase to finished rice and shows profit for every lot.
Per lotprofit and loss
Full Stack Software Engineer
Junior → Full Stack Software Engineer · 2025 — now
In use since 2026
Wet paddyDryingProductionLot profit
- to generate the report
- Seconds
- tracked through production
- Wet → rice
- The problem
- Paddy is bought by the sack and only weighed at production. Wet paddy loses weight drying, then moves through warehouses. Costing rice and by-products took constant manual work.
- The result
- Profit and loss for every production lot, which once took endless calculation, is now a report generated in seconds.
17 modules I worked on
- Lot-wise profit
- Production batches
- Production output
- Production expenses
- Paddy purchase
- Purchase challan
- Wet paddy transfer
- By-products
- Sack ledger
- Returnable items
- Stock dashboard
- Supplier dues
- Invoices
- Bank accounts
- Double-entry accounts
- Attendance
- Report suite
Used by: A rice mill · in use since 2026
Built with Angular, NG-ZORRO, Hapi.js, PostgreSQL, JasperReports
Shows domain modelling, costing logic, production workflows
High-Volume Retail ERP + Mobile App
Handles 300–400 customers and ৳12–15 lakh a day, from invoice to cash closing.
300–400customers every day
Full Stack Software Engineer
Junior → Full Stack Software Engineer · 2025 — now
In use since 2023
InvoiceChallanWarehouseCash close
- transactions every day
- ৳12–15 lakh
- selling from a phone
- Mobile
- The problem
- With 300–400 customers a day and ৳12–15 lakh in daily transactions, reconciling cash and accounts at the end of each day, week and month was exhausting.
- The result
- Invoicing, returns and reconciliation are automated, so customers get a proper invoice and the owners can focus on the business.
18 modules I worked on
- Fast invoicing
- Warehouse challan
- Mobile selling app
- Bangla invoices
- Sales orders
- Sales returns
- Credit notes
- Refunds
- Payments
- Cash book
- Bank accounts
- Stock transfer
- Product conversion
- Expenses
- Profit and loss
- Attendance
- Leave
- Report suite
Used by: A large retail shop · in use since 2023
Built with Angular, NG-ZORRO, Hapi.js, PostgreSQL, JasperReports
Shows high-volume workflows, mobile, usable ui
Wholesale Distribution ERP
Reconciles stock, sales and 15 bank accounts for a wholesaler selling nationwide.
15bank accounts in one place
Full Stack Software Engineer
Junior → Full Stack Software Engineer · 2025 — now
In use since 2024
PurchaseWarehouseInvoiceBank & P&L
- accounting core
- Double-entry
- old data migrated
- Day one
- The problem
- Stock leaving several warehouses was miscounted, purchases and sales would not reconcile, 15 bank accounts were hard to track, and exact reports for tax officials were a struggle.
- The result
- Stock, sales, purchases and bank balances reconcile in one system, with the old records migrated so the history goes back to day one.
20 modules I worked on
- Multi-warehouse
- Batch tracking
- Data migration
- 15 bank accounts
- Double-entry accounts
- Chart of accounts
- Journals
- Financial periods
- Invoices
- Purchase bills
- Stock transfer
- Product conversion
- Returns
- Credit notes
- Vendor credits
- Refunds
- Cash book
- Income & expense
- Receivables
- Report suite
Used by: A nationwide wholesaler · in use since 2024
Built with Angular, NG-ZORRO, Hapi.js, PostgreSQL, JasperReports
Shows accounting, data migration, reconciliation
Government Office Inventory
Complete inventory for a government office, from requisition to return.
Top to bottombuilt by me
Built the inventory system, top to bottom
Junior Software Engineer · 2024 — 2026
In use for about 1.5 years
RequisitionApprovalDispatchReturn
- in use
- ~1.5 years
- government database
- Oracle
- The problem
- A government office needs purchases, requisitions and stock to follow its approval rules, with a record of who received what.
- The result
- A complete inventory flow, from requirements meetings and estimation through production delivery.
12 modules I worked on
- Requisitions
- Requisition approval
- Allocation
- Dispatch
- Initial stock
- Bills & approval
- Product returns
- Return approval
- Suppliers
- Warehouses
- Store dashboard
- Reports
Used by: A government regulatory office · in use for about 1.5 years
Built with Angular, NG-ZORRO, Hapi.js, Oracle, JasperReports
Shows end-to-end delivery, approval workflows, oracle
Bookkeeping & POS App
A modern way for shopkeepers to track sales, dues and accounts. Web and mobile.
Leaddirecting 2 developers
Leading 2 developers
Full Stack Software Engineer · 2026 — now
In development
SaleDueLedgerReport
- one product
- Web + mobile
- with POS
- Double-entry
- The problem
- A shopkeeper needs to see each day’s sales, who owes what, what is owed, and whether money moved through cash, mobile or bank.
- The result
- In development as a modern, easier alternative to the bookkeeping apps already popular in Bangladesh.
10 modules I worked on
- POS
- Party dues
- Stock
- Double-entry ledger
- Cash, mobile & bank
- Personal accounts
- Business accounts
- Dashboard
- Reports
- Flutter app
Used by: For shopkeepers and individuals · in development
Built with Hapi.js, PostgreSQL, Flutter
Shows technical leadership, product thinking
SMS & Email Gateway
One gateway for 15–20 companies, sending 1.5–2 million SMS a month with full delivery logs.
15–20companies
Built the dashboard and frontend
Junior Software Engineer
Used by 15–20 companies
AppGatewayProviderDelivery log
- SMS every month
- 1.5–2M
- provider can be registered
- Any
- The problem
- Every application needs to send SMS and email, and someone has to see what was sent, what failed and how many times it was retried.
- The result
- One gateway carrying about 1.5–2 million SMS a month, with a delivery record for every message.
8 modules I worked on
- Provider registration
- Access keys
- Bulk SMS
- Delivery logs
- Failure tracking
- Retry tracking
- Email delivery
- Dashboard
Used by: Used by 15–20 companies
Built with Angular, NG-ZORRO
Shows dashboards, platform thinking, high volume
Multi-Tenant, Multi-Branch System
Purchasing and inventory across branches nationwide, from requisition to delivery.
Multi-tenantarchitecture
Worked on purchase and inventory
Junior Software Engineer · 2024 — 2025
In production
RequisitionQuotationPurchaseDelivery
- branches in use
- Nationwide
- The problem
- Many branches across the country need to work in one system, with tenants and branches kept apart.
- The result
- Runs across the branches nationwide without a major incident.
11 modules I worked on
- Purchase requisition
- Quotations
- Purchases
- Delivery
- Suppliers
- Products
- Departments
- Branches
- Roles & users
- Dashboard
- Report suite
Used by: Branches across Bangladesh
Built with Angular, NG-ZORRO, Hapi.js, PostgreSQL, JasperReports
Shows multi-tenancy, production reliability
Care Home Inventory
Unpaid social work: tracks stock, expiry and what each resident receives.
Pro bonosocial work
Built the inventory system
Junior Software Engineer · 2025
In production · Pro bono
PurchaseStockResidentExpiry
- and source tracked
- Expiry
- The problem
- A care home has to know what each resident received and still needs, how much food is in stock, what to buy, and what is about to expire.
- The result
- One system for running the home’s stores, built as unpaid social work.
10 modules I worked on
- Stock by warehouse
- Resident allocation
- Purchases
- Product returns
- Stock adjustment
- Disposal
- Expiry tracking
- Suppliers
- Dashboard
- Reports
Used by: A home for elderly people · pro bono
Built with Angular, NG-ZORRO, Hapi.js, PostgreSQL, JasperReports
Shows social impact, inventory
(03) — Skills
What I reach for, and how often.
No progress bars or made-up percentages — just honest tiers.
Every day
Angular
Versions 14 to 20 in production, with Signals and standalone components.
RxJS
Streams for search, forms and live data across busy admin screens.
NG-ZORRO
Dense data tables, forms and modals across the ERP systems I work on.
TypeScript
Front to back. Types are documentation the compiler checks.
Node.js · Hapi.js
The backend of every ERP I ship at work — plugins, validation, structured routes.
PostgreSQL
Schema design, PL/pgSQL, indexing, row-level security, PostGIS.
JasperReports
Pixel-exact salary sheets, payslips and bank reports.
REST APIs
Validated, role-protected endpoints for web and mobile clients.
Git · GitLab
Branches, merge requests and weekly releases to production.
- Comfortable with
- NestJS
- Oracle Database
- Docker Swarm
- Nginx
- GitLab CI/CD
- Redis
- Flutter
- Dart
- In the toolbox
- JavaScript
- PrimeNG
- Angular Material
- Tailwind CSS
- Bootstrap 5
- Highcharts
- Chart.js
- Express.js
- TypeORM
- JWT
- RBAC
- PostGIS
- Flyway
- ExcelJS
- Leaflet
- Python
- Bash
- Linux
- Postman
- DBeaver
- Mocha
- Chai
- Jest
- Go
- Studying now
- System design
- Saga · CQRS · Outbox
- OAuth 2.0 / OpenID Connect
- PostgreSQL HA — Patroni, PgBouncer, pgBackRest
- NestJS internals
(04) — References
From the people I work with.
“After several unsuccessful attempts with other vendors, Atiar and his team delivered our university’s Payroll & Personnel system within three months. He took the time to understand government payroll rules and handled the details with care. Work that once took a week or more now takes just a few hours, with fewer errors. What I value most is his dedication to seeing the work through. I would confidently recommend him for complex enterprise software projects.”
“Atiar is someone I can trust to take ownership of a module, from the first requirements discussion through to production. On our payroll system, where a single rule can affect the salaries of 1,500 people, I particularly value his attention to detail. He asks the right questions early, keeps the team moving, and takes responsibility for what he delivers. As his team lead, I know I can rely on him without constant follow-ups.”
“I worked closely with Atiar on the delivery of our HRMS and ERP modules, and I appreciated how well he understood our HR needs and turned them into practical solutions. He takes ownership, supports his teammates and shows sound judgment in different situations. He respects company policies and brings the same team spirit to office sports and activities that he brings to his work. With his positive attitude and ready smile, Atiar is someone colleagues can rely on and enjoy working with.”
(05) — What I do
You bring the rules. I make them run.
Angular frontends
Fast, dense, keyboard-friendly interfaces for people who use them eight hours a day. Signals, standalone components, clean upgrades.
Complex grids & forms · Dashboards & charts · Angular version upgrades · Performance tuning
APIs & databases
Node.js APIs with Hapi.js or NestJS on PostgreSQL or Oracle — schemas that stay correct and fast as the data grows.
REST API design · PL/pgSQL & query tuning · JWT, RBAC, OIDC · Flyway migrations
Reports that reconcile
Salary sheets, bank statements, payslips and stock reports that match the ledger every single month.
JasperReports · Excel exports · QR-verifiable documents · Category-wise sheets
Have a system in mind?
Even if it is only a spreadsheet today — that is usually where the rules are.
(06) — About
Structures are designed before they are built.Software too.
Full Stack Software Engineer building ERP, HR and accounting systems for government and enterprise clients. 3+ years of taking work from the first requirements meeting to the production release.
The foundation
I started out drafting buildings — a diploma in Civil Technology taught me that good structures are designed before they are built. I taught myself software and never looked back.
The craft
I care about the parts users never see — salary engines that reconcile to the taka, schemas that survive audits — and the parts they do, which should feel effortless.
Education
- 2015
Diploma in Engineering — Civil Technology
Khulna Polytechnic Institute
- 2011
Secondary School Certificate — GPA 5.00
Raj Textile High School, Jessore
Languages
- Bangla — Native
- English — Professional
- Hindi — Conversational
What three years taught me
- 01Design before building. A wrong schema costs more than any wrong screen.
- 02Talk to the people who will use it. Requirements live in their day, not in the ticket.
- 03Ship weekly, small and reversible. Release notes are part of the release.
- 04Boring tools that work in production beat exciting ones that look good in a README.
(07) — Writing & teaching
Learning in public, in Bangla.
I write long-form courses so the next developer in Bangladesh can learn in their own language.
Learn Dart & Flutter
48 weeks · 336 lessons · Bangla
A day-by-day course from zero to professional — real-life examples, runnable code, edge-case practice and self-checks.
Go Mastery Roadmap
345 days · 60 DSA problems
Prerequisites to Go internals and cloud infrastructure, with a tested data-structures & algorithms track.
TypeScript Mastery
Book · Bangla & English
A bilingual TypeScript book, from the type system to real-world projects, built to a printable PDF.
(08) — Contact
Let’s build something solid.
Hiring a Full Stack Software Engineer, or need an ERP, payroll or HR system designed from the schema up? My inbox is open.