No publisher. No university. No company. One person, working in his spare time, without ads or a paywall. That is the setup behind one of the most quietly impressive educational projects on the internet — and it recently shot to the top of Chinese social media, where a Zhihu post praising it collected over 1,600 upvotes and 3,600 saves in days.

His name is Bartosz Ciechanowski. He used to be an iOS engineer. On weekends, instead of gaming or scrolling, he writes physics, math, and engineering articles that you do not read so much as operate.

Open his article about mechanical watches, and you can drag the watch to spin it around, pull a slider to peel the case away, hand-wind the crown yourself, and slow down time to watch the escapement tick, click, and release. Every one of these demos is real-time 3D running inside the browser. There is not a single video.

Thousands of Words, Dozens of Hand-Written Visualizations

His catalog reads like a physics syllabus with the boring parts removed: the Moon and ocean tides, GPS satellites, internal combustion engines, how a bicycle stays upright. Each article runs to several thousand words with dozens of hand-coded interactive diagrams.

The Moon piece, for example, drops you into a cosmic sandbox where you can drag planets, tweak velocities, and watch gravity bend their paths. The GPS article renders orbiting satellites and lets you explore the timing physics that makes positioning work. The bicycle article literally balances itself on your screen as you steer it.

All of it is written, modeled, and programmed by one person — with the polish of a small studio's product and the focus of a single obsessive mind.

"Better Than a University That Charges You Tens of Thousands of Dollars a Year"

The Zhihu post that went viral is blunt about the contrast. A quoted comment from the author of the similarly excellent site ciechanow.ski (Bartosz himself) puts it directly: the quality is better than universities that charge tens of thousands of dollars a year.

The comment section adds a layer of context that feels increasingly rare. One reader joked that the site cannot possibly be AI-generated — it does not even break chapters into separate pages, everything is crammed onto one page. Another noted it is not quite a systematic textbook, but as popular science it is excellent. A third asked whether it is better than Feynman's lectures; the reply: that is a priceless manual for immortals, ordinary readers need only a bit of aptitude.

The humor masks a serious point that resonates in 2026, when AI can generate text, images, and video on demand: the most admired educational content right now is the stuff that a machine could not have made. The value is not in the words — it is in the thousands of lines of carefully reasoned interactive code, the months of iteration, the judgment about what to show and when. That is exactly what generative AI is worst at reproducing.

No Ads, No Paywall — Just Patreon

The site carries no advertising and no subscription wall. If you enjoy the articles, there is a Patreon. That is the entire business model. In an ecosystem where attention is monetized aggressively, the deliberate absence of monetization has itself become part of the appeal — and a standing argument that genuinely useful educational content can survive on goodwill and small donations.

For anyone wondering what humans still do better than models: this. A single engineer, a browser, and the patience to make physics feel tangible — an encyclopedia you can grab, spin, and take apart with your own hands.

Experience Now

References:

[1] Bartosz Ciechanowski — interactive physics, math, and engineering articles: https://ciechanow.ski/

[2] Article archives: https://ciechanow.ski/archives/