testing

Sandi Metz's RailsConf 2013 talk offers practical guidelines for deciding what to test and how, so tests stay cheap and stable. She argues for testing the public interface rather than implementation and using mocks appropriately.

Will Wilson explains autonomous testing: using deterministic simulation and fuzzing, building on FoundationDB's approach, to test software continuously. It sets out the ideas behind his later company Antithesis.

John Hughes, co-creator of QuickCheck, talks about property-based testing of hard systems. He shows production examples where it found very low-level bugs, including issues in the CAN bus standard.

Hillel Wayne's PyCon 2018 talk on testing beyond pytest and mypy. It introduces property-based testing with the Hypothesis library and design-by-contract with dpcontracts, and shows how to combine them with an existing test suite.

Alen Ladavac of Croteam talks about continuous integration and automated testing pipelines in games, with case studies from The Talos Principle and Serious Sam.

Will Wilson of FoundationDB explains how the team tested their distributed database using deterministic simulation. By running the whole system in a simulator with injected faults and reproducible seeds, they could find rare concurrency and network bugs.

Veritasium tells how Kodak film was fogged by radioactive fallout from the first atomic tests, letting the company detect nuclear testing before anyone announced it. The video also covers the deal to keep it quiet and how fallout contaminated packaging.

Builder Matt Risinger freezes water-filled copper and PEX piping capped with SharkBite fittings to see which survives. The video compares how each pipe type handles freezing.

Adam Neely tests the claims for tuning to A=432 Hz by trying the unusual tuning systems that its proponents' numerology requires. He compares how they sound against standard tuning and temperaments.

Veritasium's Derek Muller spends an hour in a silent, dark anechoic chamber at BYU to test the claim that 45 minutes is the most anyone can bear. He reports on his experience and other people's reactions.

Short footage from a NASA space suit test in which a technician is exposed to near-vacuum after an accidental depressurization. It shows the instantaneous effects on a human body.

Gary Bernhardt's RubyConf 2012 talk on testing in isolation without mocking everything. It goes through behavior versus data, mutation versus immutability, and how a functional core with an imperative shell yields natural isolation and parallelism.

Raymond Hettinger's PyBay 2018 keynote on preventing, finding and fixing bugs under a time budget. He covers testing practice, type annotation tradeoffs and the limits of coverage metrics.

J. B. Rainsberger argues that large integrated tests are a scam: they are slow, fail opaquely, and give a false sense of coverage. He advocates focused collaboration and contract tests at boundaries instead.

Deviant Ollam, head of a physical penetration testing team, presents tactics for getting into buildings, from bypassing door levers with a wire to defeating bank doors. He argues that physical security is often surprisingly weak.

Ian Cooper's DevTernity talk revisits Kent Beck's original TDD ideas and shows where misunderstandings crept in. It argues tests should target behaviors through public interfaces rather than implementation details, so suites support refactoring instead of resisting it.

Gil Tene of Azul Systems explains common pitfalls in measuring latency and response time, including why averages mislead and the problem of coordinated omission. He introduces open source tools like HdrHistogram for better measurement and reporting.

A Thoughtworks conversation among Martin Fowler, Kent Beck and David Heinemeier Hansson on whether TDD is dead. They discuss the tradeoffs of test-driven development, mocking and where TDD helps or hurts design.

Jim Coplien and Bob Martin debate test-driven development and unit testing in an InfoQ video that grew out of a JAOO 2007 dispute. They also touch on design and architecture.

Brandon Rhodes' PyOhio 2014 talk on applying the Clean Architecture in Python. He shows how this high-level design pattern fits Python's features and addresses maintainability problems in large applications.

Stuart Halloway of Cognitect argues for debugging with the scientific method: form hypotheses, try to falsify them, and write everything down. The talk is given to the Clojure community but applies to any language.

Isao Hashimoto's time-lapse map shows all 2053 nuclear explosions between 1945 and 1998, with each nation getting a blip and a running tally. Each second represents one month.

Scott Manley tells the story of a computerized telemetry system built to sit at the heart of a nuclear test device in place of the plutonium pit, designed to transmit data in the microseconds before it was destroyed.

Titus Winters' CppCon 2017 talk argues for C++ and Google's Abseil to be maintained as a live at head language, relying on testing and automated tooling rather than never changing or promising no compatibility. It covers Hyrum's law and the limits of semantic versioning.

Deviant Ollam's two-hour conference talk explains how elevators work, from the pit and buffers to the car top, controller logic and access-control features. It shows how this knowledge can be used for optimization and for bypassing building security.

Deviant Ollam and Howard Payne give an in-depth DEF CON 22 explanation of how elevators work, from the pit to the penthouse. It covers their control modes and how pen testers use elevators to bypass building security.

Deviant Ollam shows that most physical attacks on doors bypass the lock, with photo and video examples of how doors, frames and hardware get defeated. It is a physical security talk from Shakacon.

Jake Vanderplas's PyCon 2016 talk shows how sampling-based methods such as simulation, shuffling and bootstrapping make statistics intuitive. His pitch is that if you can write a for-loop, you can do statistics.

Jayson E. Street's DEF CON 19 talk shows photos from real security engagements where he was already inside client facilities, illustrating how social engineering and physical intrusion can cause huge losses. For each attack he also explains what defenses would have stopped him.

LockPickingLawyer cuts through a LiteLok flexible bike lock with cable cutters in about 16 seconds, one of several videos defeating the product.

A timeline visualization plotting the 2053 nuclear tests and detonations from 1945 to 1998 on a world map, with sound marking each blast. It conveys the pace of the nuclear arms race.

Sandi Metz takes an ugly section of conditional code and refactors it into a few simple objects, bridging object-oriented theory and practice. The talk includes her take on the Gilded Rose refactoring kata and the idea that duplication is cheaper than the wrong abstraction.

Bret Victor's talk at CUSEC 2012 in which he argues that creators need immediate feedback and should organize their work around a guiding principle. He demonstrates live-coding and animation tools that show results as you type, and describes his own principle that creators must see what they are making.

Rafal Dittwald's Clojure/north talk shows how to move from writing Java-style code in Clojure to thinking in data-driven, functional terms. He walks through a JavaScript example, refactoring imperative code step by step into a functional core.

Bryan Cantrill's GOTO Chicago 2017 talk on debugging production systems under pressure, centered on the incident where an operator's mistyped command rebooted an entire Joyent datacenter. It covers human factors, automation and architecture.

Emery Berger explains why performance is hard to measure and deliver on modern hardware, showing how code layout and alignment can swamp optimization effects. He presents Stabilizer for statistically sound evaluation and Coz, a causal profiler.

Russ Cox gives a 23-minute tour of the Acme text editor from Plan 9, showing its mouse-driven interface, executing commands from text, and its filesystem-based interface to other programs.

Linus Torvalds gives a Google tech talk on git, the source control system he created two years earlier. He argues for distributed version control over centralized systems such as CVS and Subversion.

A thoughtbot meetup talk by Max Cantor on getting most of what popular plugins provide using only built-in Vim features. It covers autocomplete, file jumping, filesystem navigation, build integration and snippets, with slides and a vimrc available.

Tavis Rudd describes how RSI forced him to program by voice, and shows the Python and Emacs Lisp system he built with voice recognition. A live demo creates and deploys a small system without touching the keyboard.