Full-Stack Engineer · Indonesia · GMT+7

Hanna Tiara Andarlia

I started in frontend and learned my way to the end of the pipeline — idea, API, mobile, web, release — by watching how people actually use what I ship.

The lattice is the golden angle from the mathematics I trained in. The travelling ring is the front of the harvested invasion my thesis modelled. The swell is the sea the software ships to. Touch the water. The spiral arms are not drawn, count them: consecutive Fibonacci numbers.

I build end-to-end software for fleet operations — work orders and planned maintenance, assets and component hierarchies, inspections, defects and certificates, inventory and procure-to-pay, multi-tier approvals and fleet analytics. Most of my code is the offline app crews use at sea, where there is no network to fall back on.

vessels running the platform: 100+
merged pull requests: 1,000+
real users: 1,000+
in production software, 5 remote: 6 years

Read the case studies hannatiara@gmail.com

Open to full-remote engineering roles · comfortable with AU, SG and EU overlap

Selected work

What the problem turned out to be

All 6

012024–2026

Reported: “Records keep reverting.”

Offline drafts had no owner, so the newest work lost

Not sync frequency. Offline drafts had no ownership, so a device that had been away could land stale state on top of newer work — and nothing in the model could make that write fail.

React Native · Expo · WatermelonDBRead

022025–2026

Reported: “There are rounding errors on the requisition totals.”

Every level could tax an already-taxed amount

Not rounding. Tax and discount lived at several levels at once, so every level was individually defensible and the total was still wrong — collapsed into one ladder with no second rung.

NestJS · MySQL · SequelizeRead

032025–2026

Reported: “All tests are green — we should be fine to release.”

"All tests green" meant nothing, so I froze the debt by name

Inherited authorization gaps meant a passing suite proved nothing. Fixing them first would have blocked every release for months, so they were frozen by name — old debt cannot pass, new regressions show the day they land.

Playwright · MySQL · TypeScriptRead

042025–2026

Reported: “Approvals are wrong for this customer.”

One hard-coded approver did not survive the second customer

The obvious fix was a branch per customer, which compounds forever. Instead the business configures its own ladders, spending authority and price guards, and a new customer costs no code at all.

NestJS · Next.js · React NativeRead

Practice

How I work

Problem framing before code: I take the ambiguous version of the request, find the rule underneath it with the people who live it, write the specification, then build the most ideal implementation through a reliable program.
Designed so the next change is configuration: Approval hierarchies, spending authority and charts of accounts are configured, not branched per customer. Every customer organisation runs its own rules with no code change.
Release quality as a system: 1,000+ deterministic cases and 2,000+ authorization decisions per run, with inherited debt quarantined by name so it cannot count as a pass.

Before software

Applied mathematics, and the habit it left behind

BSc Mathematics, Universitas Indonesia. One of my two published papers is an agent-based contagion model. It runs live on the about page, because a model you can move is a better argument than a citation.

Run the model