Building with AI. Sharing the useful bits.

Seoul
I asked Claude Opus 5.5 to explain how a jet engine works by building one in code and taking it apart. Cut it open, follow the air through row after row of compressor blades, into the flame, then out past the turbine that spins the whole thing.
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A submarine dives by letting the ocean in. Vents open, air rushes out of the ballast tanks and seawater floods in. At zero weight in water, small wings fly it down. This Short got 1.8K views on YouTube. Every frame was built in code by Claude Code. No 3D software.
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Meanwhile, my results from letting Claude run a YouTube channel: 11 Shorts ~15,000 views 12 subscribers $0.00 Every 3D model, script and voiceover was made by Claude Code. No yacht yet, but every number is real.
Day one of letting claude trade my 1 lac trading account. 1.54cr after charges 🙏 Markets are kind, some days ❤️
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Everyone posts the "$8k/month faceless channel" screenshot. Here's a real one, 10 days in: 11 Shorts ~14,000 views 10 subscribers $0 earned I never opened a video editor. Claude Code built every 3D model, wrote the scripts, made the voice and rendered it. What the numbers taught me 👇
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1. What worked: a person in danger or an absurd number. Ejection seat: 2.4K. "80 trillion calculations a second": 2.1K. A $200M chip-making machine, objectively wilder, got 630. 2. The 8-minute long versions of the same videos got under 100 impressions in their first month. Shorts did all the work. 3. Same videos on TikTok: one got 78% of its views from the Philippines. Where you post from decides who sees it first. Next 10 days I'll post every number here, good or bad.
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I asked Claude Opus 5.5 to explain how a jet engine works by building one in code and taking it apart. Cut it open, follow the air through row after row of compressor blades, into the flame, then out past the turbine that spins the whole thing.
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The full 9-minute version uses the same 3D model and answers the part this clip skips: why the turbine blades sit in gas hotter than their own melting point and survive. youtu.be/S9eM3bMSDKk
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Guess what this 660-ton steel ball is doing near the top of Taipei 101. It hangs on cables between the 87th and 92nd floors. It's not decoration. Wrong answers welcome. I'll post the real one under this.
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The answer: it's a tuned mass damper. When wind or an earthquake pushes the tower, the ball swings to the same rhythm and pulls back the other way. That can cut the building's sway by up to about 40%. In Typhoon Soudelor in 2015 the ball reportedly swung around 1 m.
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Power off on an iPhone isn't off. It's a smaller machine. The screen, cameras and main chip go dark. One rail stays live, and three radio chips on it keep working for up to 24 hours. That's the cutaway I want to build next: everything black except those three.
When you shut down a modern iPhone, the Power Management Unit (PMU) cuts voltage to the main A-series processor, the OLED display, and the camera array. It leaves a separate Low Power Mode (LPM) rail live on the motherboard. Sitting on that energized rail are three wireless chips: the Bluetooth controller, the NXP NFC controller, and the Apple U1 Ultra-Wideband chip. Apple built this hardware partition to run "Findable After Power Off," Express Transit passes, and Digital Car Keys when your battery dies. Even with iOS completely unloaded from RAM, those three chips stay powered for up to 24 hours on a manual shutdown (and up to 5 hours on automatic battery reserve). Right before iOS powers down, it pre-computes 96 rolling NIST P-224 public keys (one for every 15-minute window over the next 24 hours) and sends them to the Bluetooth chip using Host Controller Interface (HCI) commands. The final HCI command severs communication with the main processor and starts a standalone thread inside the Bluetooth silicon. While the main SoC sits unpowered, the Bluetooth chip wakes up every 2 seconds to broadcast the current P-224 public key over Bluetooth Low Energy. Any passing iPhone or MacBook that hears that broadcast encrypts its own GPS coordinates with your broadcasted public key and relays the packet to Apple servers. In 2022, researchers at the SEEMOO lab at TU Darmstadt audited this low-power hardware chain ("Evil Never Sleeps") and found a major gap between the three wireless chips. While the NFC chip runs encrypted and signed firmware and the U1 Ultra-Wideband chip checks cryptographic signatures at boot, the Broadcom Bluetooth chip has neither encryption nor signature verification on its firmware updates. Broadcom bakes its base Bluetooth firmware into read-only Mask ROM at the factory. To fix bugs and load the standalone Find My feature, iOS writes raw binary patches directly into the chip internal SRAM using a mechanism called PatchRAM (Write_RAM HCI commands). The hardware never checks a cryptographic signature on those RAM patches. If an attacker already has kernel-level code execution on iOS (through spyware or a local jailbreak exploit), they can overwrite the Bluetooth chip PatchRAM in SRAM before the user powers the phone down. When the user drags the power-off slider, iOS halts and wipes main system RAM. Because the PMU keeps the LPM power rail alive, the modified Bluetooth firmware stays in SRAM and keeps executing on reserve battery power. Worse, the TU Darmstadt team showed from iPhone board schematics that the Bluetooth and U1 chips are wired directly to the Secure Element inside the NFC controller via dedicated hardware buses (SE_I2C and R1_WAKE/SYNC) so car keys and transit cards work while the phone is off. Compromised Bluetooth firmware running in LPM can broadcast custom tracking beacons, listen for over-the-air wake commands, or talk directly to the Secure Element over SE_I2C while the main operating system is dead. Apple lets you tap "Temporarily Turn Off Finding" on the shutdown screen and enter your passcode to disable LPM for that power cycle. That toggle works if your phone is clean, because a clean iOS kernel tells the PMU to cut the LPM rail. If your phone is already compromised by kernel spyware, the malware controls the shutdown sequence. It can turn off the screen, play the shutdown animation, ignore your toggle, and tell the PMU to keep the patched Bluetooth chip powered in the background. Once kernel malware can hide inside unverified radio SRAM, a software power-off slider means nothing. Until the battery is physically disconnected from the board or the phone goes inside an RF-shielded Faraday bag, the Bluetooth silicon can stay on the air.
Community note
This is a 2022 proof of concept, not a new discovery. It required prior privileged access to modify Bluetooth firmware on older iPhones. The study documented no real-world attacks, and this post provides no evidence that current models remain vulnerable. arxiv.org/abs/2205.06114 arstechnica.com/information-te
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A jet engine is allowed to fail this test. They fire a bird of up to about 3.6 kg (8 lb) into the spinning fan. The blades can bend. The engine can even shut down. The one thing it must never do: catch fire or throw broken parts out through its case.
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I build 3D teardowns of machines with AI and make every part inside move. Which one should I open up next?
0% Rotary engine
0% Camera shutter
0% Toilet tank
0% Zipper
0 votes • Final results
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Why did the SR-71 leak fuel on the runway? At Mach 3 its titanium skin got so hot it grew. So the panels were built loose, with room to expand. Cold: gaps, leaks. Hot: sealed. What should I open up next?
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She doesn't exist. Neither does the mask. One AI photo of the same face, then 15 seconds of AI video. This is take 7 of 10. Hardest part: her face has to survive the peel. Some tries came back as a slightly different person.
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Inside a car engine.
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This still blows my mind. Every few days I crack open one thing you wear or hold all day and make every part inside move. This time it's a mechanical watch. No battery. Just a spring, a few gears and one tiny lever. > The lever stops the whole gear train 8 times every second, then lets it go. That's the tick. > That's 691,200 stops a day, on your wrist. > The balance wheel swings back and forth 4 times a second, and that steady swing is the only thing keeping time. > Wind it once and the spring alone keeps it going for well over a day. Built in code with Claude. No keyframes.
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Here it is moving. 14 seconds, balance wheel first.
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A still teardown names the parts. Motion shows why they're there. Pin lock below: 5 spring-loaded pin stacks. A key has exactly one job, lift every split to the same line at the same moment. In a still you see pins. When the key slides in, you see the lock decide.
Added a new skill: /teardown It creates a technical illustration of any object and lets you customize individual parts, colors and annotations. You can then export the result as an SVG or PNG. npx skills add jakubkrehel/skills
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One prong on a US lamp plug is wider than the other. It's not a mistake. > The narrow slot in the wall is the hot side. It carries the live voltage. > The wide slot is neutral, the return path. > The lamp's switch is wired to cut the hot side, so when it's off, the bulb socket isn't live. > If the plug could go in backwards, that socket could stay live with the switch off. Touch it while changing a bulb and that's a shock. The wide prong only fits one way, so the hot wire always lands where the switch can cut it. Built in code with Claude. No keyframes.
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Don't hand an agent your server with "fix any security issues everywhere." Scope it: one service, read-only first, a list of proposed changes you approve. My own agents run behind a hook that refuses commands touching keys or accounts they shouldn't. Slower, and the only reason I let them run unattended.
Fix the security issues on your server with this prompt for Codex/GPT-6 Astra. You can try Claude Code/Opus 5.5 too but the stupid auto classifier may block you. You need to have connected your Codex project to your server via ssh before. "Go online and research all the things that have happened in information security in the past 5 days. Today is October 24, 2026. Then fix any security issues everywhere in the server. Ask me questions if you need to."
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This skincare creator doesn't exist. Every video starts as one AI photo of the same face, then 15 seconds of AI video from that photo. The hard part isn't the video. It's keeping her the same person every single time.
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