I am a product leader and design engineer. I moved closer to code so I could ship the whole loop myself, then measure what changed.
Product, Design & AIEngineer
I build product systems and leave the instruments behind to measure them. Since 2008.


What makes a product system worth trusting?
A machine now works at every stage of making a product. I build what it works inside: the criteria it reads, the system it draws from, the gate it cannot talk past.

01 · ResearchCriteria
The machine reads the market; the criteria decide what counts.

02 · SpecAcceptance
The machine drafts the spec; acceptance is what it can be held to.

03 · DesignSystem
The machine generates the screens; the system is why they come out on-system.
--ctl-32: 32px; --r-pill: 9999px; --dur-base: 200ms;
04 · BuildGate
The machine writes the code; the gate refuses what it cannot prove.
- routes gated
- errors, last run

05 · MeasureRegistry
The machine reports the numbers; the registry makes each one carry its source.
- people reached
- daily active users
- lower operations cost
Until 2026, no title I ever held said engineer.
Read three cases in full
Each case carries its own measured numbers. They live inside the case, and every one of them resolves through the dedicated Evidence page, grouped by how it was measured.
Nice to meet you
- Jun 2026 – nowPrincipal Product Engineer
- Jan 2026 – nowFounder & Chief Product Engineer
- 2023–2026Head of Design
- 2021–2022Head of Digital Product
- 2018–2021Product Design Manager · Growth
- 2016–2026Founder
- 2017–2018Senior Product Designer
- 2014–2015Senior UI/UX Designer
- 2013–2014Senior Web Designer
- 2008–2021Creative Director
- 2006–2010BSc Computer Science
- 2020Silver Stevie®
- 2020Bronze Stevie®
- 2020International Finance Awards
- Dec 2024Top 10 · Product Design
- 2016 – nowUX Hacker
What I hold to
The work is not the screen. The work is the change it creates.
On outcomes A claim ships with its evidence in the same viewport, or it does not ship.
On evidence Every number here resolves to how it was measured, or it is not a number.
On measurement
Builder Receipt · GITHUB · RCPT №001
Jang Trịnh
Product designer who ships systems