From AI idea to a product worth using
I’m Carlos Lastres, a design engineer based in Tokyo. I bring an MBA, an Apple Design Award and experience shipping my own apps to the decisions that shape yours.
An Apple Design Award winner with an MBA and a background in software engineering
That combination changes how I make decisions upstream. You stop designing for an idealized version of the product and start designing for what can actually be built, maintained, and grown.
My work has shipped to millions of users across education, SaaS, Web3, health tech, and consumer apps. I have taken brands from zero to millions of impressions, led design for products at the frontier of AI and consumer tech, and sat on founding teams whose products went on to define their categories.
Living in Tokyo sharpened everything. The city holds a standard for craft, service, and attention so high that mediocrity stands out immediately. I bring that lens to every product I touch.
I speak Spanish, English, Japanese, and Chinese, which means I can work with your team and your users wherever they are.
Apple Design Award 2025, Inclusivity
Apple hands out a handful of these a year, across the whole App Store. Mine came for accessibility work on Speechify, software people use because reading the normal way does not work for them.
It sits this high on the page for one reason. Everything else here is me telling you the work is good. This is the part where somebody else said it, and the somebody else was Apple.
- Category
- Inclusivity
- Year
- 2025
- Product
- Speechify
Official Claude Partner
Anthropic recognised me with the Claude Partner Badge, in Claude Code. It is the tool I build with every day, so nothing I say about shipping with AI is theoretical.
The mark behind this text is being drawn by the same point cloud that has followed you down the page. That is roughly the argument. I do not talk about AI, I build with it, and this site is one of the things it built.
- Programme
- Claude Partner Badge
- Specialisation
- Claude Code
- Recognised
- 2026
Apps owned by me
Client work is most of what I do, and most of it is under someone else’s name. These three are mine end to end: my idea, my design, my code, my name on the App Store listing.
What I can do
Most products ship the interface the team could build, not the one people actually needed. I start from how someone moves through your product, then design the surface around that. Research, flows, prototypes, the screens you actually ship. Retention is the number that moves first.
I build and ship apps and websites end to end. Because I write the code, the handoff problem disappears. Nothing gets designed that cannot be built, and nothing gets built that quietly drops the design.
A brand nobody sees is just a style guide. So I do both halves: the branding and visual design that make you recognizable, and the articles, pages and video that put you in front of people. One hand on both, which is why they never drift apart.
Plenty of products are loved and still do not make money. Pricing, packaging, the paywall and the moment you ask for the upgrade are design problems long before they are spreadsheet problems. I have shipped these on real subscription products and watched the revenue move.
Confusing buyer journeys usually get answered with more marketing spend. That is expensive and it treats the symptom. I fix the journey instead, so the same traffic converts and comes back.
Latest works
What changes when design and code are one job
Design gets treated as the part you do at the end, after the real decisions are made. It is the opposite. By the time an interface exists, most of the money has already been won or lost upstream, in choices nobody labelled as design at the time.
Every case study on this site lists what was actually measured, with the baseline where I have it. No industry averages standing in for my own results.
Design that cannot be built gets quietly redrawn by an engineer at 2am, and the compromise is what ships. I write the code, so there is no second version of the product that nobody signed off on.
Most design arguments are business arguments wearing a design costume. Someone has to say out loud what the company is actually optimizing for. With the MBA in the room that happens in the first meeting instead of the fifth round of mockups.
Fifteen years of client work, from a two person startup to a film studio and a public sector rollout. The ones I can talk about are written up, with the numbers, under Work.
Three TEDx stages. The United Nations
Talk 01 — Tokyo, JP
TEDx Innovation
Watch ↗
Talk 02 — Awaji, JP
TEDx Awaji
Watch ↗
Talk 03 — China
TEDx ZSJU
Read ↗
Speaker at the United Nations, with work featured in international media across three continents.
On the record
“Carlos handled all of our product design and frontend UI/UX work during rapid development of our job board platform. I highly recommend him!”
“Carlos has contributed so much in bringing Web3Auth’s UX forward, really appreciate all the work he has done.”
“It’s always a pleasure to work with Carlos. He has good communication skills. He can transform ideas into designs and implement those designs in a clean and nice front-end.”
“A great marketing director makes your job easy and that’s what Carlos did. He’s extremely organized, highly communicative, and efficient in all aspects of his role.”
In the press
Covered in English, Spanish, and Japanese, across three continents.
Writing about my work? Biographies, high resolution photography and the sources behind everything I argue are ready to use.
Latest posts
If you need a designer who understands your business goals, let’s talk
Data-informed decisions. Work that actually converts.