Building business systems that stay correct under pressure.

I build full-stack TypeScript systems with explicit transaction boundaries, traceable engineering decisions, and verification tied to public evidence.

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OhMyPos cashier interface showing branch selection, product cards, an active two-item order, and payment-method controls. — Cashier workflow with branch-scoped availability, active order detail, and payment-method selection.

Selected work / OhMyPos

Correctness across sales, inventory, and financial ledgers.

Multi-branch POS

One operational system, multiple consistency boundaries.

A multi-branch POS system built to keep sales, inventory, and financial ledgers consistent under concurrent transactions.

Recorded result

30 concurrent settlement requests resolved into exactly 15 successes and 15 conflicts, with a final balance of Rp0.00and zero server errors.

Next.js
NestJS
PostgreSQL
Prisma

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Engineering focus

From business rule to verifiable behavior.

Transaction correctness

Model invariants, concurrency paths, and failure states before treating a workflow as complete.

Full-stack ownership

Connect interface behavior, API contracts, domain rules, and persistence decisions into one inspectable system.

Evidence-led delivery

Bound public claims to reproducible tests, documented trade-offs, and artifacts that reviewers can inspect.

Professional approach

Technical depth should remain easy to inspect.

My portfolio separates facts from claims: each case study states its constraints, records trade-offs, and keeps limitations visible alongside the outcome.

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Open a conversation

Looking for a Software Engineer who makes system behavior inspectable?

Start with the public work, then reach me directly by email or LinkedIn.

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