repl-driven development

Ruby developer Avdi Grimm gives a seven-minute tour of Pharo Smalltalk's development environment, focusing on tools like search-by-example and the integrated, live coding experience.

A Computer History Museum demonstration with Dan Ingalls of Smalltalk-76 running on a Xerox Alto, recorded in 2017. He shows the live environment and discusses the system.

A GameTrailers walkthrough from E3 2012 of an Unreal Engine 4 real-time tech demo with Epic's Alan Willard. It shows live code changes and hot reloading while the game runs.

A 1991 NeXT promotional video that stages a head-to-head programming contest between a NeXT computer and a Sun workstation. It shows NeXT's interface builder and object-oriented tooling producing an application far faster than traditional UNIX development.

A short demo of Code Bubbles, an IDE interface built around editable code fragments in bubbles instead of files. It was a research prototype for Java development.

A timelapse of Notch (Markus Persson) creating his Ludum Dare 21 entry, Prelude of the Chambered, from scratch in 48 hours.

A timelapse of Notch (Markus Persson) making Metagun, a game built from scratch in 48 hours for Ludum Dare 18. It shows the whole coding session sped up.

A 35-minute demonstration of NeXTSTEP Release 3 by Steve Jobs. It shows the object-oriented development environment and features such as dragging a live chart between apps.

LabCoatz uses mass spectrometry, with help from other science YouTubers, to reverse engineer the Coca-Cola flavor and builds a chemically-identical replica. The video walks through a year of work on the formula.

Bruce Hauman live-codes Flappy Bird in ClojureScript in about six minutes, using figwheel to hot-reload changes into the running game. The demo shows game behavior being changed interactively without restarting.

A demo of the Symbolics Graphics Division's S-Packages, a Lisp-based 3D color graphics and animation system from the 1980s. It was later used in developing for the Nintendo 64.

A 1975 live demonstration of the APL language by Imperial College professor Bob Spence, showing a REPL on a modified typewriter terminal and APL's appeal to non-programmers.

Steve Jobs demos NeXTSTEP Release 3, showing the object-oriented development environment and UI that later became the basis of Mac OS X. Midway through he builds a database-backed GUI app with Interface Builder and Enterprise Objects Framework with almost no code.

A Gource visualization of 826 days of Minecraft development, from alpha 1.2 to release 1.5, condensed into eight minutes. Each dot is a file, folders are links, and developers fly around zapping files as they work on them.

The Godot Engine 2022 showreel of apps and tools built with Godot, with a timestamped list of each project. It shows the engine being used well beyond games.

A live mock programmer interview in which Casey Muratori interviews game developer Shawn McGrath using a less confrontational format devised by Chris Hecker. It gets deep into technical details while showing how the candidate actually thinks and works.

Symbolics developer Kalman Reti gives a short introductory demo of a Symbolics Lisp Machine running Genera in an emulator. It shows the context-aware command line, typed on-screen objects, and the live-editable system, including swapping in a C-compiled JPEG decoder.

Allan Blomquist demonstrates the internal programming and debugging tools Tomorrow Corporation uses to make games, including live modification of a running game and time-travel debugging.

AngeTheGreat describes building a physically realistic internal combustion engine simulator in C++, drawing on fluid dynamics, physics and chemistry. It generates procedural audio for engines such as a V8.

Stargate Studios' 2009 virtual backlot reel shows before-and-after shots in which green screen and compositing replace locations in ordinary TV dramas and comedies. It shows how much of a seemingly real show is computer generated.

In the finale of Double Fine's Devs Play, speedrunner SMK demonstrates glitches and exploits that skip entire sections of Psychonauts while Tim Schafer and the dev team watch. The developers react to and discuss the bugs as they appear.

Andreas Kling ports the game Diablo to SerenityOS, his from-scratch Unix-like operating system, using the devilutionX project. The roughly 80-minute session shows what porting third-party software to the OS involves.

Stuart Halloway introduces REBL, a graphical, interactive tool for browsing Clojure data, extracted from Datomic tools. The talk is from Clojure/conj 2018.

A five-minute video showing how to build a counter in the Imba web programming language in under a minute, then style it.

A five-minute demo of a live ClojureScript game editor by Chris Granger. It is based on Bret Victor's demo from the Inventing on Principle talk, with code changes reflected instantly in the running game.

A Microsoft Flight Simulator Feature Discovery episode in which CEO Sebastian Wloch explains the new aerodynamics simulation for the 2020 release.

A five-minute demo of the Common Lisp debugger fixing a bug, recompiling a single function, and resuming execution from the failed stack frame. It shows how to avoid re-running long computations.

Researchers from the Artificial Life Lab Graz introduce the Primordial Particle System, where a simple motion law for self-propelled particles produces cell-like structures that self-reproduce and show life cycles.

A short Dyalog demonstration building Conway's Game of Life in a single line of APL, step by step. It shows how array operations replace loops.

A short clip of the McMurtry Speirling fan car setting a new Goodwood Hill record of 39.08 seconds at the 2022 Festival of Speed, driven by Max Chilton. It beat the previous timed shootout record set in 1999 and the outright record held by the VW ID.R.

John Carmack live-codes a simple VR application at Oculus Connect 2 using a Racket-based environment for rapid development and deployment on Gear VR.

Stuff Made Here builds a handwriting robot and sends its output to a handwriting expert to see whether it can pass as forgery. It walks through the engineering trials and errors along the way.

A demo of the 8pen, a gesture-based keyboard replacement for touchscreens that lets users enter text by moving around a circle. It is meant for phones, remotes and game controllers and mimics handwriting.

David Heinemeier Hansson builds a blog engine with Ruby on Rails in 15 minutes, the demo that launched Rails' momentum.

A Tiny Desk concert in which pianist Dan Tepfer plays with a Disklavier player piano driven by a program he wrote that responds to his playing. He performs four pieces from his Natural Machines project.

A Primitive Technology episode in which the creator builds a bow-drill-driven bark fan to blow air into a fire, using only natural materials. It shows the progression from fanning a fire by hand to a rotary forge blower.

Adam Savage shows off his collection of analog calculators, ending with a 3D-printed, scaled reproduction of the Curta mechanical calculator built by Marcus Wu. The video examines the replica and the engineering behind it.

A promotional video for Leap, the navigation technology invented by Jef Raskin, demonstrated on the Canon Cat computer around 1987. It shows keyboard-driven search and cursor positioning in place of a mouse.

Stuff Made Here builds a device that lets a blind person perceive their surroundings by touch, using an iPad's lidar and a mechanical tactile display driven by motors. The video walks through the build and the limits he hit.

Valve opens up a Steam Deck to show its internal components and explain which are replaceable or upgradable. It advises against self-repair but shares the details openly.