Hacker News Daily — June 21, 2026

29 stories · June 21, 2026

Plus This issue is new — delivery and download are for Plus until it ages into the free archive.

In this issue

1

Loupe – A iOS app that raises awareness about what native apps can see

github.com · 493 points · Discussion

Loupe is an iOS and iPadOS app that gives you a hands-on tour of the device fingerprinting surface. It reads real values from public iOS APIs, the same ones any third-party app can call, and shows…
2

Beyond All Reason (Free Total Annihilation Inspired RTS)

beyondallreason.info · 375 points · Discussion

Real-Time Strategy Redefined Every unit, projectile and explosion simulated in real-time Unmatched Scale & realism All units and projectiles are simulated in real-time. The game offers fully simulated…
3

Identity verification on Claude

support.claude.com · 365 points · Discussion

https://old.reddit.com/r/ClaudeAI/comments/1ubm53n/official_...
4

Prefer duplication over the wrong abstraction (2016)

sandimetz.com · 355 points · Discussion

I originally wrote the following for my Chainline Newsletter, but I continue to get tweets about this idea, so I'm re-publishing the article here on my blog. This version has been lightly edited. I've…
5

Slow breathing modulates brain function and risk behavior

cell.com · 355 points · Discussion

Read via the links — full text wasn’t available.
6

The brain was not designed for this much bad news

sciencedaily.com · 339 points · Discussion

During several recent conversations, people have told me that they’ve stopped checking their phones in the morning. Not because nothing was happening, but because everything was. They described the…
7

Developers don't understand CORS (2019)

fosterelli.co · 329 points · Discussion

Developers don't understand CORS July 10, 2019 — Chris Foster One of the best things about working in full stack consulting is that I get to work with a great number of developers with different skill…
8

Renting a sewing machine from the library

bbc.com · 325 points · Discussion

Oodi Library, Helsinki (Credit: Oodi Library, Helsinki) Finland's libraries are increasingly being valued not by how many books they lend, but how they help societies function. On a freezing January…
9

Epoll vs. io_uring in Linux

sibexi.co · 246 points · Discussion

First, I want to tell you how exactly I got to this point and why I started researching different options for handling asynchronous I/O on Linux… Last year, my students and I built a reverse proxy…
10

Show HN: TownSquare, a tiny presence layer for websites

townsquare.cauenapier.com · 231 points · Discussion

https://cauenapier.com/blog/townsquare_release/ https://cauenapier.com/blog/townsquare/
11

15-minute at-home Lyme disease tick test

bostonglobe.com · 212 points · Discussion

https://archive.ph/cNwmN
12

Running MicroVMs in Proxmox VE, the Easy Way

taoofmac.com · 193 points · Discussion

Jun 18 th 2026 · 15 min read · #containers #homelab #kvm #microvm #proxmox #qemu #virtualization I’ve been running a mixed Proxmox cluster for years – four nodes of wildly different capability, from…
13

(How to Write a (Lisp) Interpreter (In Python)) (2010)

norvig.com · 139 points · Discussion

Why does this matter? As Steve Yegge said, "If you don't know how compilers work, then you don't know how computers work." Yegge describes 8 problems that can be solved with compilers (or equally well…
14

A 3D voxel game engine written in APL

github.com · 133 points · Discussion

This started off as a bet with myself that APL notation would provide an easier way to make a voxel game. This is highly experimental and buggy. Controls W-A-S-D to move Space to jump Mouse to move…
15

Fossil Fuels Are 40% of Freight Shipping Tonnage, but Half Its Fuel Use

cleantechnica.com · 122 points · Discussion

Shipping’s transition starts by shrinking the fuel pool, then using electrons and scarce liquids only where they fit. Support CleanTechnica's work through a Substack subscription or on Stripe.…
16

Burnout is real for open source maintainers

openjsf.org · 101 points · Discussion

For more than a decade, Lodash has been one of the most widely used libraries in the JavaScript ecosystem. Its utilities appear in countless projects, often quietly working behind the scenes, and…
17

Excessive nil pointer checks in Go

konradreiche.com · 84 points · Discussion

Jun 16, 2026 Let’s talk about nil pointer checks in Go. You want to prevent panics in production, but that doesn’t start with a deferred recover. It starts with defensive programming. Check your…
18

Two Qwen3 models on one DGX Spark: the residency math

devashish.me · 80 points · Discussion

My agent stack with Hermes runs on a workstation. The models run on a DGX Spark on the same LAN. The split is deliberate: the workstation stays responsive, the Spark does the GPU work, and they talk…
19

JSON-LD Explained for Personal Websites

hawksley.dev · 79 points · Discussion

JSON-LD, also known as JSON Linked Data, is a format for adding structured data to webpages. It can aid web crawlers in understanding the semantic structure of your site, qualifying you for richer…
20

Proportional-Integral-Derivative (PID) controllers

en.wikipedia.org · 77 points · Discussion

A proportional–integral–derivative ( PID ) controller, or three-term controller, is a feedback -based control loop mechanism commonly used to manage machines and processes that require continuous…
21

The minimum viable unit of saleable software

brandur.org · 74 points · Discussion

Last week I wrote about leaving Stainless and my intention to work on building my side project River into a small, sustainable business. When I sent that letter, a few people asked about my thought…
22

An Embedded Linux on a Single Floppy

github.com · 35 points · Discussion

FLOPPINUX 💾 An Embedded 🐧Linux on a Single 💾Floppy FLOPPINUX is a complete Linux distribution that fits on a single 1.44MB floppy disk. Think of it as Linux From Scratch but for making single…
23

System call instrumentation on Linux/x86‑64 using memory‑indirect calls, part I

humprog.org · 34 points · Discussion

Diverting trains of thought, wasting precious time 15 06 2026 --> Mon, 15 Jun 2026 System call instrumentation on Linux/x86-64 using memory-indirect calls (in vain?), part one My libsystrap library…
24

Occupancy Math on the AMD MI355X: A From-First-Principles Guide

indianspeedster.github.io · 33 points · Discussion

Ask a GPU kernel engineer how their kernel is doing and occupancy comes up within a sentence or two. It’s the number everyone quotes and the dial everyone reaches for — and, in my experience, the…
25

Show HN: Pulse – Dashboard for Claude Code, approve tool calls from your phone

github.com · 22 points · Discussion

Hi everyone, I'm a student from Flanders and I like to use Claude Code for my purposes, ideas and also just for fun and also make solutions for problems in our world!) So that's why I built "Pulse",…
26

Show HN: CleverCrow: give tokens to your favorite projects

clevercrow.io · 17 points · Discussion

Howdy all. I'm Zack:wave:. I've been thinking about the problem of misguided AI pull requests and figured I'd throw a possible solution out there for feedback. Basically, CleverCrow lets supporters…
27

Cocktail Optimization, an Integer Programming Problem

bunkum.us · 13 points · Discussion

June 18, 2026 I’ve been interested in integer programming problems for a long time (they the most interesting problems in dedupe ). In the past, I approached them by writing custom branch-and-bound…
28

How to organize 3 acquired companies into one coherent website

littlelanguagemodels.com · 13 points · Discussion

Company A has acquired Company B, C, and D. How do we organize their sites, for multiple products with different audiences, while making it easy to find relevant product information and quickly…
29

Conway's Game of Life, in real life

lcamtuf.coredump.cx · 12 points · Discussion

Read via the links — full text wasn’t available.