Software engineer

Boy Boni Panjaitan.

I turn complex systems into useful, dependable products.

My work sits between software architecture and product craft: clear interfaces, resilient systems, and small tools that earn their place.

Pura Ulun Danu Beratan silhouetted against a sunset over Lake Beratan, Bali

Selected work

Software shaped around real constraints.

Production systems I designed and built. Client names are left out; each entry focuses on the system design and the solutions behind it.

View all work

Case study · Agritech commerce

Document-Gated Commerce Platform

One modular-monolith backend serves web, mobile, field-sales, and admin clients. Purchases that need identity and land paperwork pass AI-assisted verification before payment; stock is decremented under row locks, a worker reconciles payments, and chat scales across instances through Redis.

Modular monolith · AI document checks · GCP + Terraform

Case study · Tourism booking

Inventory-Safe Reservation Platform

Tickets, stays, timed activities, and packages share one cart and one checkout. A serializable transaction reserves stock all-or-nothing with 15-minute holds, an idempotent payment service owns every provider call, and RabbitMQ events feed separate audit and analytics services.

Event-driven services · Payments · Infrastructure as code

Case study · Professional services

Serverless Bilingual Advisory Site

A bilingual content and lead-intake site with no backend server. Firestore rules mirror the client's Zod schemas as the validation layer, App Check guards every read, and a build-time Puppeteer prerender with a generated sitemap makes the static SPA indexable.

Serverless · SEO prerendering · Security rules

Working principles

Less ceremony. More clarity.

The best engineering choices make the next decision easier—for users, teammates, and the person maintaining the system later.

Start with the constraint

Understand the operational reality before choosing the abstraction.

Make states legible

Good interfaces reveal what happened, what matters, and what comes next.

Build for the handoff

Durable software should be understandable beyond its original author.

Field notes

Thinking in public, carefully.

Short notes on engineering judgment, interface design, and keeping systems humane.

Browse all notes

Software Development

Why a Monorepo Helps Me Build a Big Project Solo

Building MySawit alone means moving between several apps and a server. Here’s how keeping them in one repository helps me make coordinated changes and manage shared code.

Web Development

How I Built a Website and Blog While Only Paying for the Domain

A personal website with a capable blog doesn’t have to come with a stack of monthly subscriptions. Here’s how boypanjaitan.com works, what it costs me today, and what to watch as it grows.

Productivity

How to Combine and Organize PDFs Before Sending Them

Bring separate PDFs into one file, put every page in the right order, and check the result before you send it.

Next conversation

Have a difficult problem worth making simpler?

Tell me what you are working on. I will reply to the email address you provide.