debugging

An overview of the PTVS 2.0 beta feature for debugging Python and C/C++ together in one session in Visual Studio.

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.

Ron Garret tells the story of the Remote Agent Experiment on NASA's Deep Space 1, where autonomous software controlled a spacecraft in 1999. He describes debugging Lisp code remotely from millions of miles away.

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.

A brief demo of the Smalltalk debugger, including defining a method that doesn't exist yet while the program is stopped mid-crash.

Bruce Waggoner of the Voyager team describes how engineers diagnosed Voyager 1's 2023 loss of telemetry and patched its flight software from 15 billion miles away. The talk covers the spacecraft's architecture and the scarcity of old documentation.

Bryan Cantrill's 2007 Google Tech Talk on DTrace, showing how dynamic tracing improves debugging of both development and live production systems. It includes a vivid war story about tracking down a problem on a Sun Ray server.

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.

A 2007 Google Tech Talk in which Bryan Cantrill demonstrates DTrace and explains how it improves debugging of both development and live production systems.

Bryan Cantrill's Uptime 2017 talk on the engineering challenges of the stateful data path, including storage, firmware and hardware bugs. It uses the 'zebras vs. horses' diagnostic heuristic to explain why rare failures keep appearing.

Casey Muratori gives a fast tour of the RemedyBG debugger for Windows, which he uses daily. He shows its speed and features, especially the watch window.

Bret Victor's talk from Dropbox's DBX conference about living by a guiding principle, in his case that creators need an immediate connection to what they are making. He shows live-coding and time-manipulation demos that let ideas take form at the speed of thought.

JPL's David Cummings presents at the 2025 Flight Software Workshop how the team diagnosed and fixed the 2023 Voyager 1 anomaly from billions of miles away. It walks through the flight computer and the memory fix.

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 1993 VHS demo of Lucid Energize, a database-backed, incremental C/C++ programming environment built on XEmacs. It shows features like incremental compilation, live debugging and hyperlinked output.

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.

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.

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.

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 three-minute Emacs Rocks screencast by Magnar Sveen demonstrating paredit, which edits Lisp code structurally as a tree of s-expressions rather than characters.

Emily Shea explains how repetitive strain injury pushed her to program by voice using speech recognition (Talon), and gives a live coding demo. She argues voice-driven development can be pain-free, efficient and enjoyable.

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.

A five-minute lightning demo of VisiData, a terminal tool for exploring and manipulating data. It uses two months of NYC 311 complaint data to drill down, plot points on a virtual map and save selected rows.

John Kitchin shows how Emacs org-mode with Python lets researchers combine narrative, math, figures and executable code in one document. It exports to LaTeX, HTML and PDF, and he used it for papers and e-books.

Joran Dirk Greef's Systems Distributed '23 talk on TigerStyle, the engineering methodology behind TigerBeetle. It covers designing safer systems in less time through up-front design, assertions, and deterministic simulation.

Jeremy Howard defends Jupyter notebooks as a serious development environment, especially when paired with nbdev. He responds directly to Joel Grus's talk about why he dislikes notebooks, and contrasts REPL-style and notebook-style work.

Steve Yegge records himself working in Emacs and shows off about a dozen features in a roughly 45-minute screen capture. It is an informal, enthusiastic tour rather than a structured tutorial.

Evan Czaplicki's Strange Loop 2014 talk surveys the many formulations of functional reactive programming and how they relate historically and theoretically. It then shows how Elm's variant enables hot-swapping and its time-traveling debugger.

Fons van der Plas introduces Pluto.jl, a reactive notebook for Julia that tracks references between cells and re-runs affected cells when code changes. The talk was given at JuliaCon 2020.

A short screencast tour of JSPM, SystemJS and ES6 features, building a small app with the then-new JavaScript module and package tooling. It shows how JSPM works as a package manager, bundler and loader.

Jay Parlar's Strange Loop talk shows how model checkers such as Alloy can find complex bugs in a system's design without running or reading any code. He walks through modeling architectures and checking every possible sequence of operations, including a real security bug and a UI feature-interaction bug.

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.

A three-minute Emacs Rocks screencast demonstrating Magit, the Git interface inside Emacs, including staging and other everyday operations.

A four-minute tour of the TeXmacs scientific editor, showing math typing, figures, citations, a drawing tool, document styles, HTML export, presentations and animations.

Max Brunsfeld introduces Tree-sitter, a parsing system for developer tools that offers incremental parsing and robust error recovery through a uniform C API. The talk explains the design, based on LR extended to GLR parsing.

Steve Yegge's Stanford seminar on GROK, Google's internal large-scale, cross-language source code analysis system. It covers how the system helps with code search and understanding across Google's huge codebase.

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.

A demo of writing technical documents in Emacs Org mode using org-babel, so that code blocks and generated content stay consistent when things change. The author shares the demo files and his dotfiles.

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.

Anders Hejlsberg whiteboards how compilers are taught versus how modern ones are actually built. He explains the shift to compilers as services with incremental, error-tolerant, IDE-oriented design, as in Roslyn and TypeScript.