limits of knowledge

James Hoffmann demonstrates his AeroPress technique with a short recipe: 11g of coffee, 200g of just-boiled water, a 2-minute immersion, then a press. He explains why he skips rinsing, preheating and inverting.

A guided Wim Hof breathing session of three rounds at a slow pace, building from a 30 second to a 90 second breath hold. An on-screen bubble animation helps you keep the rhythm.

The trailer for Tim Hunkin's series The Secret Life of Components, eight guides to mechanical and electromechanical parts for designers and makers.

Jon Gjengset's roughly four-hour live stream implementing part of a BitTorrent client in Rust, following CodeCrafters' test-guided challenge. He builds from scratch and shows idiomatic error handling along the way.

A short, sweary cooking video in which Nat makes a quick bolognese using simple pantry ingredients. It is part of his isolation-era cooking series.

Markus Triska tours Prolog's most distinctive features, including its use as a database and query language, rule processing, constraint solving and compile-time rewriting. It also covers concise meta-interpreters.

A walkthrough of installing Synapse, Riot and Jitsi from scratch on Debian to run your own Matrix communication service. The description warns it is now quite outdated and links to updated material.

The first part of a series on programming in Jai, Jonathan Blow's in-development language. It covers compiling, writing hello world and using code from other files.

In this first Crust of Rust episode, Jon Gjengset live-codes an example that needs multiple explicit lifetime annotations. Along the way he covers string types and generics over a custom trait.

Jon Gjengset's long live-coding Crust of Rust episode on async/await, focused on the mental model for using it rather than on Futures, Pin and Wakers internals. Topics include awaiting multiple futures, cancellation, executors and select.

Ben Krasnow of Applied Science uses an antique 4x5 view camera to make high-resolution photolithography masks in a home shop. He photographs a poster-sized printout onto litho film to get features around 20 microns.

A tutorial in the GAS Therapy series showing how to recreate the Teenage Engineering OP-1 and OP-1 Field with free software. It argues you do not need to buy expensive gear to make music.

Jeremy Howard's 90-minute practical tour of language models. It covers how they work, GPT-4's capabilities and limits, using the OpenAI API, code writing, data analysis and fine-tuning.

A reupload of Joel Spolsky's talk teaching spreadsheet users the Excel features they are probably missing, such as keyboard navigation, named ranges, tables and lookups. The original disappeared and this copy comes from the Wayback Machine.

Imphenzia's 83-minute tutorial covers the low poly modeling techniques he learned over five years of Blender use, with timestamps from navigation and extrusion onward. It uses Blender 2.83 with default keys.

Ian Hubert shows how to use Blender's motion tracking to turn ordinary footage of a room into a stylized digital environment for an indie film. It is a quick, practical walkthrough in his loose, lazy-tutorial style.

Blender Guru's beginner tutorial series, in which you model, light, texture and render a donut while learning Blender's core features. This is Part 1 of the Blender 3.0 version.

A 12-minute beginner lesson from Nick Milo's Linking Your Thinking series introducing the Obsidian note-taking app and the first steps to start using it.

Max Miller of Tasting History makes garum, the fermented fish sauce of ancient Rome, using a same-day recipe. He covers the history of the condiment along the way.

A short walkthrough of a hack that tricks a Brother laser printer into accepting third-party toner by working around its genuine-toner check. It notes this may void the warranty.

Animator Joel Haver explains how he makes his short films using rotoscoping and the EbSynth tool, along with the software he uses. The method is a labor-intensive, frame-by-frame process.

Inigo Quilez live-codes a cartoon character painting entirely from math, using signed distance fields in a Shadertoy shader. He explains each step of building the image from formulas.

Inigo Quilez live-paints a mountain landscape using only math in a shader, building up from a basic polynomial noise surface through fractal terrain, lighting and atmosphere. The code runs in real time on Shadertoy so viewers can edit it as they follow along.

Ben Eater explains how a USB keyboard communicates, covering the electrical interface, bit and packet encoding, packet contents, and a comparison with PS/2.

Tech Ingredients shows how to make a homemade radiative cooling paint, with a custom liquid panel that cools below ambient temperature outdoors. The video covers the materials and how to apply the paint.

NightHawkInLight shows how to make ultra-white radiative paint that cools surfaces below ambient temperature without electricity. He walks through the research papers and the household-materials process.

The first lesson of MangoJelly's FreeCAD 0.20 beginner course, covering setup, preferences and navigation. The series teaches fundamentals through complete workflows such as sketching, Part Design and STL export.

James Trunk introduces Clojure syntax and thinking, covering its core data structures, immutability, the thread-last macro and live data analysis in the REPL.

A roughly three-hour screen recording of designing a barebones STM32F4 board in KiCad, covering schematic, four-layer layout and routing, USB and a buck converter. It ends with ordering manufacture and assembly through JLCPCB.

Ben Vallack walks through designing a custom keyboard PCB from scratch using Ergogen and KiCad, ending with a gerber file ready to order from a PCB fabricator. The example is a split keyboard.

Andrej Karpathy builds a bigram character-level language model from scratch, introducing torch.Tensor and the framework of training, sampling and loss evaluation. It is the first step toward a GPT-style Transformer in his makemore series.

In a long live-coding session, Andreas Kling works on making the Cookie Clicker game playable in the Ladybird browser from SerenityOS. He tracks down bugs in the browser engine and fixes them.

This Old House's Ross Trethewey explains MERV filter ratings and how air filtration works, then shows how to build a localized DIY air filter, including a box fan with multiple filters.

Tech Ingredients shows how to build a liquid panel with a specialty paint that, placed outside, cools below ambient air temperature. It demonstrates radiative sky cooling.

Ben Eater explains how the PS/2 keyboard interface works, covering its clocked serial protocol and scancodes. He builds up the hardware-level understanding needed to read keypresses.

The Thought Emporium shows how easily bacteria can be genetically modified to produce fluorescent proteins and even bioluminesce, with techniques doable at home. It links to companion videos on incubators, DNA extraction and gels.

Loopop reviews the Polyend Tracker hardware tracker-style sequencer and walks through a tutorial from sampling to finishing a song. It covers most of the device's features.

Matt Risinger covers installing a Zehnder ERV fresh-air system in a tight passive house, explaining balanced ventilation, the benefits of heat recovery and the costs involved.

DIY Perks shows how to modify devices that use older USB connectors so they charge and connect over USB Type-C. He solders in a USB-C connector board and works through cases such as dongle-dependent gadgets and a mouse receiver.

A long Tsoding Daily programming stream in which he implements hot code reloading in C by loading a dynamic library at runtime without stopping the main program. It also touches on migrating struct versions across reloads.