# Pendar OS: Modular Monolith ERP & Operational Ledger

> Replacing a legacy admin-template workflow with a domain-driven Go + SvelteKit ERP built around strict margin tracking and a Cobalt operational ledger.

- Client: Pendar Cahaya Nusantara (PCN)
- Year: 2026
- Disciplines: Go & Fiber v3, DDD Modular Monolith, PostgreSQL & sqlc, SvelteKit, Operational Ledger UI
- Page: https://ponkster.me/case-studies/pendar-os
- Studio: ponkster.me (https://ponkster.me)
- Contact: origin.ponkster@gmail.com

## Challenge

Pendar Cahaya Nusantara (PCN) manages complex tender-based sales, procurement, fulfillment, billing, trip budgets, workforce scheduling, and general affairs. Their legacy admin-template system had no domain boundaries and zero real-time margin tracking across multi-stage tender execution.

## Approach

We architected Pendar OS as a single deployable Go modular monolith (Fiber v3, pgx, sqlc, PostgreSQL) with strict package-per-bounded-context isolation and saga-driven process flows. On the frontend, we designed a high-density Cobalt operational ledger in SvelteKit and Tailwind v4 pairing Familjen Grotesk, IBM Plex Sans, and tabular JetBrains Mono figures.

## Outcome

Unified tender sales, procurement, fulfillment, and billing under an authoritative domain model with end-to-end margin visibility and a keyboard-first operational interface.

## Results

- Single-binary Go modular monolith with strict bounded-context isolation
- Type-safe SQL queries via pgx + sqlc over PostgreSQL
- Cobalt operational ledger UI with ruled KPI rows and tabular figures

## Optional

- [Studio overview and all case studies](https://ponkster.me/llms.txt)