Linux / Arch / Waydroid などのメモ。備忘録でも、誰かの助けになりますように。
What My DIY Desktop PC Actually Cost — Core Parts Only
I went through purchase receipts and order records to reconstruct the real cost of my desktop build (main rig: takashi-pc). This covers core internal parts only — CPU, GPU, motherboard, memory, storage, case, and PSU — leaving out peripherals like the keyboard and mouse. I confirmed the CPU/GPU against the actual running machine with lscpu/lspci, and the model numbers match the purchase receipts. Parts list Part Model Vendor Purchased Cost Notes CPU AMD Ryzen 7 5700X BOX (AM4 / 8-core 16-thread / 32MB L3 / 65W TDP) Janpara (Higashi-Ikebukuro) 2025-02-23 ¥25,450 ¥24,980 minus ¥300 discount plus ¥770 shipping, 1-month member warranty, credit card GPU SAPPHIRE PULSE Radeon RX 6600 XT GAMING OC 8G GDDR6 Janpara (Akihabara) 2024-02-11 ¥28,450 ¥27,980 minus ¥300 discount plus ¥770 shipping, 1-month member warranty, paid via Paidy RAM CFD Standard DDR4-3200 16GB×2, 288-pin DIMM Amazon 2023-12-23 ¥8,883 Same order as motherboard Motherboard ASRock A520M Pro4 (AMD A520 / Socket AM4 / Micro ATX, official Japan distributor) Amazon 2023-12-23 ¥8,845 Same order as RAM SSD 1 (Windows boot drive) CFD 256GB 2.5" SATA (Toshiba) Amazon 2015-07-06 ¥13,979 My first-ever SSD, currently the Windows 11 boot drive, carried over from the previous PC SSD 2 Crucial P2 500GB M.2 NVMe (official distributor warranty, 5-year) Amazon 2022-01-04 ¥5,515 Listed at ¥5,555, minus ¥40 in Amazon points SSD 3 (added) Crucial BX500 1TB 2.5" SATA (3-year warranty, parallel import) Amazon 2025-08-05 ¥9,500 Paid via Paidy SSD 4 (Windows, in active use) Crucial MX500 500GB 2.5" SATA Amazon 2018-04-01 unknown Missing entirely from the original parts list; found via lsblk on the actual machine. Manually mounting it revealed an actively-used Windows data drive. The cost isn’t listed in the Amazon order history Case DEEPCOOL CC560 V2 (ATX / glass panel / black, Dospara-exclusive model) Dospara 2024-07-07 ¥8,027 3-year extended warranty plan CPU cooler DEEPCOOL AK400 (120mm fan / LGA1851-1150 & AM4 compatible) Biccamera.com 2025-02-23 ¥3,270 Paid in full by credit card PSU Kuroutoshikou KRPW-PT700W/92+ REV2.0 (700W / 80 PLUS Platinum) Unknown (likely Yahoo Auctions, no record) unknown est. ¥12,000–15,000 Carried over from the previous PC. Model identified directly from the unit’s label; no purchase record survives, so the cost is estimated from period market pricing, not confirmed Totals Category Amount Confirmed total for everything except the PSU ¥111,919 + PSU (estimate, not confirmed) + ¥12,000–15,000 Core-parts subtotal (PSU estimate included) roughly ¥124,000–127,000 Breakdown (confirmed spend): CPU 25,450 + GPU 28,450 + RAM/motherboard 17,728 + SSD 1 13,979 + SSD 2 5,515 + SSD 3 9,500 + case 8,027 + CPU cooler 3,270 = ¥111,919. ...
How Much Did My Modded Arcade Stick Actually Cost? I Dug Up the Receipts
My arcade stick is a HORI Fighting Stick Alpha base with almost everything inside swapped out. Every button is now a GamerFinger switch, the lever is a silenced JLF with a red spring and octagonal gate to firm it up, and I drilled an extra 20mm hole under the weak kick button. I built it around October 2025. I honestly assumed the total cost was pretty modest. This time I actually dug through my Amazon and bank order history and reconstructed the real total from receipts. It was higher than I expected. ...
Why AI Became an Existential Risk — AI's Own 'Oppenheimer's Dilemma'
Source Post: YouTube (livestream “Uga-kin” by journalist Hiromichi “Hiro” Ugaya, September 18, 2026, roughly 2 hours 47 minutes) Content: A livestream analyzing why AI company leaders themselves are now warning that continued AI development could threaten human survival, framed through Ugaya’s graduate background in nuclear strategy and international security. Transcription: Auto-generated with faster-whisper (small model, CPU, int8) from spoken Japanese, so it likely contains recognition errors, filler words, and false starts. What follows is a reconstructed summary in my own words, not a verbatim transcript. One name that came through as “Koichi Takahashi” in audio appears, based on the described background (a biologist who moved into AI research), to refer to RIKEN researcher Koichi Takahashi, and is rendered that way below. Note that this livestream is Ugaya’s personal analysis and commentary — not a peer-reviewed paper or an official report — combined with catastrophe scenarios he asked Google Gemini to generate. Much of what follows is speculation, either his own or the AI’s, not established fact. ...
Why Claude Code Deletes 80% of Its System Prompt Every Release: Boris Cherny on Building for the Opus 5 Era
Source Post: YouTube (Y Combinator’s official channel), “Boris Cherny: We Cut 80% of Claude Code’s Prompt” Content: A ~36-minute conversation between Claude Code creator Boris Cherny (Anthropic) and Diana Hu at Y Combinator Startup School 2026 Transcript: Auto-generated with faster-whisper (small model, CPU, int8), then summarized and rewritten in this article rather than reproduced verbatim Fresh off the Opus 5 launch, Claude Code creator Boris Cherny sat down for a conversation that turned into a practical look at how to build products when the underlying model keeps getting more capable — including the habit of deleting most of Claude Code’s system prompt every time a new model ships. ...
Termux's sshd Logs You In as the Same User Whatever Name You Send — Reading the Patch
I added an entry to ~/.ssh/config so I could scp images from my desktop to my Pixel 6 (running Termux’s sshd), and I put a User in it. Then I noticed: when the other end is Termux, ssh banana@<phone> and ssh root@<phone> both log in as the same user. The User line in ~/.ssh/config does nothing. It’s not a config problem — it’s how Termux’s OpenSSH is built. First, the observation $ ssh -p 8022 banana@100.65.202.69 'whoami' u0_a440 $ ssh -p 8022 root@100.65.202.69 'whoami' u0_a440 Copy banana and root both connect, and both land as u0_a440 (the Termux app’s user). The key is checked only against /data/data/com.termux/files/home/.ssh/authorized_keys. ...
I Made It Write the Rule. Three Minutes Later, Claude Code Broke It.
I spent about thirty hours with Claude Code, putting a small home-made app onto a home server. The model behind it is Claude Sonnet 5. Below, “Claude Code” means the tool; “Sonnet 5” means the habits in its output. For those thirty hours I checked every line it produced. Here are the patterns that kept coming back. This is about technical mistakes, not about how smart it is. This is a record of Sonnet 5. I haven’t used Opus or Fable, so I can’t speak to those. ...
Thirty Years of Fighting Games and Monster Hunter — What Was Good Wasn't the Game, It Was the Room
I’ve been following two things for about thirty years now: fighting games and Monster Hunter. I bought most of the hardware, and I’ve touched almost every entry in both series. But looking back, what stays with me isn’t which title was the most fun — it’s who I played with, and how. The Arcade Golden Age As a teenager I read Gamest every month. The publisher went under and the magazine folded; it became Arcadia, and I read a bit of that too. In Street Fighter I went through every version — II, II’, II’ TURBO, Super II, Super II X — and then on to ZERO, ZERO2, ZERO3, III, 2nd Impact, 3rd Strike. ...
Three treesitter Errors From Migrating nvim-treesitter master → main (Neovim 0.12)
Around the time I bumped Neovim to 0.12.4, nvim-treesitter errors started piling up one after another. Tracing them all leads back to a single fact: nvim-treesitter’s master branch is already EOL and can’t keep up with Neovim 0.12. Migrating to the main branch fixed it, but here’s the path there — plus one more pitfall I stepped on after the migration. Environment: Item Value Neovim v0.12.4 (Arch Linux) nvim-treesitter master (tag v0.10.0, frozen May 2025) → migrated to main Plugin manager Lazy.nvim Symptom 1: Opening Markdown crashes on a gotmpl parser The moment I open a Markdown file, it halts with an error (Press ENTER or type command to continue). ...
What Michael Jackson Teaches About True Strength — Why He Never Let Go of Kindness
Source Post: Instagram (posted by kanako__nakamura) Content: A video that looks back on Michael Jackson’s life to talk about “true strength” — not letting go of kindness toward others even after being hurt. Transcription: The video had no discernible narration audio and was built from on-screen captions, so this is a summary based on those captions together with the post’s caption text. When you’ve been hurt or betrayed, it’s natural to become less kind to others, or to think “I can’t trust people anymore.” The post calls that a very human reaction. But the more you learn about Michael Jackson, it says, the more one thing stands out: what happened to you and who you choose to be from here on are not necessarily the same thing. ...
The Bushido Spirit Behind the Place Name "Nogizaka" — General Nogi, General Stessel, and the Russo-Japanese War
Source Post: Instagram Content: A video, filmed around Meiji Shrine and Nogi Shrine, that introduces the bushido spirit shown by Japan during the Russo-Japanese War and traces the origin of the place name “Nogizaka.” Transcription: The video had no clear narration audio and was built from on-screen captions, so frames were extracted from the video and the captions were transcribed by hand. “The winner looks down on the loser” — that scene is not unusual anywhere in the world. The video opens by contrasting it with how Japan is said to have behaved during the Russo-Japanese War. ...