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About Petarico

Soma Yano — criador do Petarico, engenheiro de software japonês

Petarico is maintained by one person, not an anonymous company. This page exists so you know exactly who is behind the tool you're using, why it was built, and which decisions I've publicly committed to never make.

Who I am

My name is Soma Yano. I'm a Japanese software engineer based in Tokyo. I graduated in 2023 from the Faculty of Informatics at Shizuoka University (静岡大学情報学部), a Japanese national university.

From 2023 to 2025 I worked as a software engineer at Hewlett Packard Japan. In 2025 I moved to HCLTech, where I continue to work as a full-time software engineer.

Petarico is my personal side project — built in evenings and weekends outside my main job. It's not a venture-backed startup, it's not my employer's product, it has no team. It's me, an AWS server, and a few decisions I committed to never break.

Why I built Petarico

The idea came from a real problem I had myself. Before an international flight, I wanted to save a few YouTube videos to my phone to watch offline during the flight. I looked for sites that would convert them and what I found was frustrating: every site was covered in aggressive ads, several crashed mid-conversion, some redirected me to casino landing pages, and none of them worked consistently.

I thought: "this is a simple need, there should be a reliable browser-based tool that requires no install, no signup, and no invasive ads". Since I couldn't find that tool, I decided to build it.

Petarico was born from that personal frustration. Every technical and product decision comes from one question: "would I actually want to use this myself?".

How Petarico is run

Alone. No employees, no co-founders, no contracted freelancers. All the code (React + TypeScript frontend, Python FastAPI backend, AWS CDK infrastructure) is written and maintained by me.

Server costs (AWS Lambda, S3, CloudFront, DynamoDB) come out of my own pocket. There's no investor, no VC money, no seed round. It's a personal project funded by my day job salary.

About money and ads

Petarico is free because if I charged for it, it would defeat the original purpose — I wanted a tool I could use myself without friction. Paying a monthly fee to convert one video is friction.

There is a paid credit option for users who want to go beyond the monthly free limit. But casual use (a few conversions a month) stays free forever, with no account, no card.

On ads: I tried putting Google AdSense on the site to cover part of the server cost. I removed it. The reason is simple: AdSense on music or religious content shows casino ads, sports betting ads, and predatory loan ads, and that goes against the kind of experience I want to offer. Petarico's content pages today have no AdSense.

Things I'll never do

These are public commitments. If Petarico ever violates any of them, please call me out:

  • Never sell user data. Not under any circumstances, to anyone.
  • Never use dark patterns (deceptive buttons, ads disguised as 'download', fake system error pop-ups).
  • Never require an account to use the basic tool.
  • Never install Facebook Pixel or third-party cross-site tracking cookies beyond Google Analytics (used only to understand aggregate site usage).
  • Never place casino or gambling ads on religious or children's content.
  • Never take money to recommend a competitor tool without clearly labeling it as advertising.

Outside work

I like to read in places surrounded by nature. I'm particularly interested in history of science and business case studies — understanding how small decisions became large outcomes, and how real people solved real problems.

How to reach me

If you want to verify my identity or talk about Petarico, these are the channels: