About me

I learned by shipping work that could not hide behind a slide.

I started in self-taught web development, joined The Hacking Project’s third cohort in 2018, and trained at 42 Paris. I later worked on the 42 Network intranet and helped launch 42 Lisboa. Ethereum, Bitcoin, and AI product work followed. Today I work independently across AI systems, product engineering, and technical publishing.

The short version

I am most useful when the answer is unclear but the consequences are real.

That has meant campus software used by students and staff, smart contracts handling live launches, Bitcoin operations under volatile fees, and AI workflows that still need a person to own the outcome.

Background

The route here was not linear.

Each role added a different view of reliability: as a student, an employee, a founding-team member, a product engineer, and an independent builder.

Jan–Mar 2018

The Hacking Project

I joined the third cohort of this early French peer-learning programme. Three intensive months of Ruby, Rails, object-oriented programming, web development, and group projects turned earlier self-teaching into a more systematic full-stack practice.

Read the full THP experience

Evidence and context 04

THP alumni testimonyOfficial first-party record THP programme historyOfficial cohort context Malt education recordPublic professional profile Rails activity, March 2018Contemporaneous public activity

2018–20

42 Paris

Project-based computer science training across algorithms, systems, networks, and web engineering. At 42 Paris, I also completed D+HINKING ACADEMY’s five-day Design Thinker programme in December 2018.

Evidence and context 02

Design Thinker certificateVerified credential · December 2018 LinkedIn — Design Thinker credentialPublic credential record · December 2018

2020

My Jungly, Paris

Full-stack product development for the Paris digital studio before returning to the 42 ecosystem.

Evidence and context 01

Tony at My Jungly — 5/5 Malt reviewVerified client rating · 15 October 2020

2020

42 Network

Full-stack work on the student intranet with the development team inside the 42 Paris Bocal.

Evidence and context 04

42 API — official resource and endpoint documentationOfficial first-party record 42 Paris — the Bocal and campus facilitiesOfficial role context Otmane B. — Malt recommendationPeer recommendation from École 42 Julien Lange — Malt recommendationPeer recommendation from École 42

2020–21

42 Lisboa

IT & Pedagogy and full-stack work across campus tooling, candidate journeys, access controls, and early operations.

Evidence and context 03

42 Network — Lisboa’s first-year launch progressOfficial first-party record Essential Business — first 150-student programmeContemporary launch coverage Julien Lange — 42 Lisboa founding-team announcementContemporary team post, published before the first Piscine

2021–25

Web3 and Bitcoin-native products

I built Ethereum and Bitcoin products with Yakuza Inc., Tokentech, OrdinalsBot, Pizza Ninjas, Pizza Pets, 0N1 Force, and other teams. The public trail spans verified Solidity, mainnet launch transactions, and permanent Bitcoin inscriptions.

Evidence and context 10

Malt — public Web3 project recordsPublic role and project scope NFT Academy — Yakuza Inc. public launch post on X (Twitter)First-party public recognition · February 2022 Ethereum Stack Exchange — Solidity activityContemporaneous public activity Etherscan — verified Yakuza Inc. contractVerified on-chain artifact Etherscan — verified Surrealestates ERC-721Verified on-chain artifact Etherscan — verified Shuttle Pass ERC-1155Verified on-chain artifact Etherscan — NOTACOMPANY contractPublic Ethereum contract Etherscan — AYA STELLAR contractPublic Ethereum contract BaseScan — EVA by Virtuals tokenPublic Base contract Pizza Ninjas — official Pizza Ninja #1 inscriptionPermanent Bitcoin artifact

Now

Independent AI and product engineering

Building AI workflows, production software, owned products, and websites that are easier to find and understand from Ericeira.

Working principles

How I work when the stakes are real.

I make trade-offs explicit.

A technical decision is only useful when the team understands what it gains and what it makes harder later.

I keep people responsible.

Automation needs clear approval points, failure paths, and a named person who owns the outcome.

I prefer proof to polish.

A working product, a public contract, a real input, or a measurable result carries more weight than a perfect slide.

I reduce dependency.

A good handoff leaves the team able to understand the work and make the next decision without me.

Official identity

The public record.

Full name: David Dacruz
Role: Independent AI & Full-Stack Product Engineer
Based: Ericeira, Portugal
Languages: French, English, Portuguese
Official website: daviddacruz.dev
Public contact: hello@daviddacruz.dev

LinkedIn GitHub DEV WhatsApp Instagram Wikimedia Commons Stack Overflow Ethereum Stack Exchange

The work is the useful version of the biography.

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