Muhammad Ilham
Rafiannandha

WORLD 3

The Dirt

Three systems, dug out and cut open. The problem, the decision, the part that was hard.

ISP PLATFORM

Twenty-seven modules, eight databases, one deployable

An ISP is three businesses in one trench coat: a network, a subscription, and a payment processor. The interesting part was keeping them in one system without letting any of them corrupt the others.

• PENDING
• provisioned
• ACTIVE
• past due
• OVERDUE
• grace over
• ISOLATED
• unpaid
• TERMINATED

↶ payment settled → reconnected in real time, straight back to ACTIVE

• 27 modules
• 8 PostgreSQL databases
• Spring Modulith
• hexagonal · DDD
• event-driven
• money as integer cents
• double-entry ledger
• HMAC-verified callbacks
• idempotent VA registration
• FreeRADIUS AAA
• MikroTik PPPoE
• CoA disconnect
• auto-isolation
• Duitku + BRI BRIVA

PT Surya Bestari Lestari · SBLNET · architecture write-up

PAYMENTS

Proving every rupiah actually moved

Somebody has to prove that what the gateway thinks happened, what the bank says happened, and what the back office recorded are the same three things.

• 3RD-PARTY SETTLEMENT
• match against
• BANK MUTATION
• then against
• BACK OFFICE

↓ whatever does not line up falls into one of three shapes

• DISPUTE AMOUNT
• MISSING IN BANK
• MISSING IN B.O.

• two-stage reconciliation
• settlement vs bank mutation
• then vs back office
• dispute detection
• missing-in-bank
• missing-in-back-office
• merchant disbursement
• fees · chargebacks · adjustments

PT Cashlez Worldwide Indonesia · CashUp

TICKETING

Built for a queue, not for a demo

A park gate is not a web form. The queue does not wait, and a forged ticket has to be refused while the person holding it is standing there.

• SCAN QR / BARCODE
• VERIFY
• THERMAL PRINT

• FORGED → REFUSED AT THE GATE

• React Native · Expo
• QR + barcode scan
• thermal printing
• forged-ticket rejection
• public ticketing site
• back office

GlobalTix Teknologi Indonesia · Taman Safari Bogor · domestic.tamansafaribogor.com

WORLD 4

The Mines

Everything shipped. Some of it is behind a client's login, and says so.

SBL NET Fiber ISP — subscriber platform, billing, provisioning LIVE Read the full story ↑

Taman Safari Domestic ticketing, back office and a gate-checker app LIVE Read the full story ↑

Elteyba Tours Umrah & Hajj agency platform LIVE Elteyba Go Pilgrim portal — itineraries, payments, documents LIVE ArkaLearn Japanese-language EdTech feeding a job portal LIVE CoffeeLabs Company site LIVE CoffeeLabs HRIS Attendance with GPS geofence and face recognition LIVE CoffeeLabs Admin Back office console LIVE Itoya Self-photo studio booking and remote studio management LIVE Big Property Apartment and room booking platform LIVE White Box Daily and transit apartment rental LIVE Gudang Dus B2B custom packaging catalogue LIVE Taiba Cococha Trilingual site (EN/ID/AR) and a sales CRM LIVE Hasanain Center Company profile and registration system — only the Instagram presence is public SOCIAL ONLY ISP Architecture Case study — how the 27-module platform is laid out SOURCE mfu-macos Python CLI for Xiaomi's bootloader-unlock API on macOS and Linux SOURCE

Cashlez Finance Portal Two-stage settlement reconciliation, disbursement, deduction CLIENT SYSTEM Read the full story ↑

CoffeeLabs POS Point of sale, inventory and income journal CLIENT SYSTEM

CoffeeLabs Notifier NestJS WhatsApp gateway for automated notifications CLIENT SYSTEM

ProSpark LMS Laravel LMS for workforce training — Singapore CLIENT SYSTEM

Spectro Job portal placing Indonesian workers in Japan, with SSW visa documents CLIENT SYSTEM

SmartHajj Hajj logistics — seat quotas, visa tracking, manifests CLIENT SYSTEM

Nghbr React Native app for a hyper-local tech network — New York APP

Remedi React Native wellbeing app on a Laravel API APP

Aerocam Drone training centre — the 2021 build was his ARCHIVED

DPUPR Musi Banyuasin Government portal on a purpose-built Laravel CMS ARCHIVED

newstvri.com News site — full stack, during the TVRI internship ARCHIVED

Six sit behind a client login, two shipped to an app store, and three are switched off. They are listed anyway, labelled for what they are, because leaving them out would make the record shorter than the work.

WORLD 5

Strata

Eleven roles as layers. The deeper you dig, the older it gets.

1. Dec 2025 – PRESENT

   Senior Full Stack Engineer

   PT Surya Bestari Lestari · SBLNET

   Fiber ISP for residential and business subscribers. Architected the core platform.

2. Mar 2025 – Dec 2025

   Full Stack Developer

   PT Cashlez Worldwide Indonesia

   Payment gateway for merchants. Built the portal that verifies every settled transaction.

3. Jun 2023 – Feb 2025

   Full Stack Developer & Team Lead

   PT Cyber Lab Indonesia · CoffeeLabs

   IT consultancy behind the CoffeeLabs suite. Led the team and ran the internship programme.

   AT THE SAME TIME

   • Jul 2024 – Aug 2024

     ProSpark Pte Ltd · Singapore

     Laravel LMS for workforce training.

   • Nov 2023 – Jan 2024

     Taman Safari Bogor · GlobalTix

     Ticketing site, back office and an Expo gate-checker app.

   • Sep 2023 – Dec 2023

     PT Arka Spektrum Solutindo

     Multi-language job portal placing Indonesian workers in Japan.

   • Jun 2023 – Aug 2023

     Nghbr Inc · New York

     React Native app for a hyper-local tech networking platform.

4. Nov 2022 – May 2023

   Full Stack Engineer

   Remedi Indonesia

   Personal and corporate wellbeing platform. Owned the mobile and backend architecture.

5. Apr 2021 – Nov 2022

   Full Stack Developer

   PT Elteyba Medina Fauzana

   Licensed Umrah and Hajj travel agency. Built the agency platform end to end.

6. Feb 2020 – Apr 2021

   Full Stack Web Developer

   PT Taiba Cococha Indonesia

   Coconut-shell charcoal exporter. Trilingual site and a sales CRM with 2FA and audit trails.

7. Mar 2017 – Sep 2017

   Full Stack Web Developer · Internship

   TVRI

   Maintained the front end of tvri.go.id and did full stack work on newstvri.com.

WORLD 6

Core

The bottom of the world. Write to him here.