Product Engineer · Indonesia UTC+7

Dicki Fadilah

I build the product and the system underneath it.

Eight years of building the whole stack, from the database to the screen in your hand.

Selected work Get in touch

01 About

Between the system and the screen

Most of my work sits where technical complexity meets product decisions.

The pattern that keeps repeating: understand the system well enough to break it into simple pieces, build a rough version fast, then make it survive production.

A system can be technically sound and still produce a confusing product. I try to make both hold up, starting from the problem rather than the spec. The spec is usually someone's best guess.

02 Capabilities

What I do

Four kinds of work I keep coming back to.

01

Product engineering

Features end to end, where the product decision and the engineering decision are made together.

end to end
02

Systems

Reliable systems around complex business logic, data, state, and third-party integrations.

logic · data · state
03

Prototyping

From idea to working software fast, so the team decides on a real thing.

idea · interaction · software
04

AI-assisted development

Using AI coding tools daily, while still deciding myself what to build, what to trust, and what to throw away.

tools, judgment
03 Selected work

Selected work

The larger projects of the last few years. Some details are simplified because of NDAs.

01 Social trading platform

A social network inside an investing app

Problem
The app had nowhere for investors to talk to each other. A social network inside it also had to stay clean, because a feed in a trading app fills up fast with spam, scams, and bad advice.
Worked on
Everything from the server to the mobile app. A personal feed and a trending feed, posts that tag stocks and people, short videos, price predictions that get checked later, shareable profit cards, automatic translation, and social moderation.
Outcome
Investors now talk about stocks without leaving the app.
fig. 02: one post, from publish to feedchecked by AI before it can rank

02 Live trading stream platform

A live show you can trade from

Problem
Investors wanted market insight from an investment analyst, on top of the charts. The answer was a live show inside the app, where the analyst walks through the market, viewers ask about their stocks, and the stock on screen is one tap from a trade. It had to stay smooth while hundreds of thousands of people get notified at once.
Worked on
The whole live screen: the analyst's video, the stock on screen with a Trade now card, viewer requests and comments, pinned official replies, gifts and reactions. Reminders before each show, and the team's tools to schedule a show and switch the active stock while live.
Outcome
A live show inside the app: an analyst, the stock on screen, and a trade one tap away.
fig. 03: a live show, one tap from a traderequests in chat · analyst switches the ticker

03 Portfolio reports engine

Showing people how much they actually made

Problem
The number users check most is their profit or loss. It has to be right every time, including after events like a stock split, when one share suddenly becomes several and the price changes overnight.
Worked on
The engine that works out each user's average cost, profit, and total return from their full trading history. Tools to repair and recalculate past data when something was off.
Outcome
Every screen shows the same numbers, and each one can be explained.
fig. 04: many events in, a few numbers outreplayed in order

04 Money ledger

Keeping track of every dollar

Problem
When an app holds its customers' money, every deposit, purchase, and sale has to match the broker's own records, every day, down to the cent.
Worked on
A ledger for every money movement. A guard against spending more than you have, even when you tap buy many times at once. Paying the broker on time, a daily comparison with their records, alerts when the two disagree, and a dashboard where one person submits a payment and another approves it.
Outcome
The system catches mismatches before a customer notices them.
fig. 05: balances explained by their eventsledger · settlement · reconciliation

05 Paper trading

Practice accounts that behave like real ones

Problem
New investors want to try before they put real money in. Experienced ones want to test an idea without risking anything. The app only had real accounts.
Worked on
Several practice accounts per user, each with a name, colour, and icon, funded with virtual cash on creation. The same order types as a real account, including bracket orders and limit orders that renew themselves.
Outcome
Users can practise with the real app, and no paper order can ever reach a real account.
fig. 06: paper accounts beside the real onesame orders · separate money

Also

06

Managed portfolio product

Portfolios run by professional analysts that users can follow and invest in, from the analysts' tools to the performance charts and notifications users see.

product · tooling
07

Internal tools & AI

Dashboards the finance and operations teams use every day, and a safe way for AI assistants to look things up in company systems, with stricter limits on anything risky.

ops · ai
04 Timeline

Timeline

2018

Web developer straight out of vocational high school. Learned engineering by shipping web applications.

first job
2019

Maintained and extended a hotel management system, and learned how to change software that a business depends on every day without breaking it.

maintenance · product
2020

Built an academic information system from scratch, from the data model to the interface.

from scratch
2021

Joined a certified digital signature provider, building signing products where cryptography, identity verification, and legal compliance have to hold together.

security · compliance
2024

Moved to a US stock trading platform: social, live shows, paper trading, portfolio reports, and the ledger underneath.

fintech · now
05 Contact

Have something worth building?

I'm glad to talk about complicated problems, early product ideas, or the systems behind them. Email is the most reliable way to reach me.