Mobile dev has learned to never block main thread for years. For us, web dev, I’m sure we were frustrated with slow scrolling side, click a button and the site seems freeze. And maybe we start make less network call, reduce the bundle size and so on. But it goes beyond that, the code is fine, they aren’t slow but they block the main thread. We learn about it here.

Kevin made a circuit-board business card with an NFC chip and a batteryless LED powered by the phone tapping it. The hardware worked, but ordinary iPhone NFC apps couldn’t format the blank NTAG I²C Plus chip. He wrote a tiny Core NFC app that sends the chip’s native commands directly, and now each tap opens my site and lights Charizard’s tail.

features a randomly generated 8x8 board, lets you open cells with left click, toggle flags with right click, opens cells with zero neighboring mines recursively, and has basic win detection. How is this even possible???

In the day of AI, anything without physical confirmation, can be easily to be a “hack” or “workaround” with the LLM. SSH is the key to the kingdom. Today, we learn how to setup Secure Enclave to authenticate SSH. The nice thing about it is that the key cannot be extracted out. Mean if you migrate to a new laptop, the secure enclave seed won’t follow you. Very secure, but also a rough edge.

Imagine ordered a 100 GbE server, then expected things to just work. Imagine OP’s surprise when the server crashed when serving at just 20 Gigabit.

A custom property answers differently depending on whether you registered it. Unregistered, it stays a raw token stream and its functions evaluate wherever you var() it - so sibling-index() reads the child’s position, not the parent’s. Register it with @property and it computes at the declaration instead. Same trap for em, ch, lh, container query units and relative URLs.

B-Tree is very common in Database like Postgres, MySQL. But there are RocksDB, Cassandra, Pebble which use LSM Trees, and many other key-value storage use it. One simple way to look at them is LSM trees optimize for heavy write, data is written in chunk, immutable, append only.

Nine animated videos from BitLemon: how a cache is organised inside the CPU, the L1/L2/L3 hierarchy, SRAM vs DRAM, replacement and write policies, the four C’s of misses, then two episodes building a cache simulator in C++. A memory round trip costs about a hundred cache hits, so most slow code isn’t doing too much work, it’s laying its data out badly.

It’s always good to know how to do something. Like my wife said, youc an order food, but better if you can cook yourself. In this seris, we learn about many concept of practical PostgreSQL. Practical mean we will facing them every single day and anyone run a PostgresSQL db with modest workload face these sooner or later.

Just as I said above. Let learn system inside out. Alexander Kuleshov’s home for linux-insides, now with a proper reader around it: 64 chapters of kernel internals read straight from the source - boot, interrupt gates, syscall dispatch, timers, spinlocks, memblock, per-CPU variables. Beside it, a seven-part x86-64 assembly series and Field Notes on real performance investigations.

A small transformer trained from scratch in 1.5 hours on one 5090 - beats many LLMs on ARC-AGI-1, matches TRM/HRM, costs 67 cents. The ablations say two choices carry it: 3D RoPE and a per-puzzle embedding, and dropping either turns 44% into 24%. The odd bit the author can’t explain: removing input tokens from the loss makes test loss worse while the score goes up.

In previous issue we mention SIMD. In this we will learn how Debian Code Search ditch cgo, rewrite with Go 1.26’s experimental simd/archsimd. The Go rewrite beat C, helped by AVX512 kernels and a positional popcount trick worth another 2x - though the post is honest that backporting both to C puts Go at about 1.4x slower.