Mark Williamson

Today we're announcing Claude Code plugins! anthropic.com/news/claude-co… It's the first major feature in Claude Code that I've gotten the opportunity to lead, and I'm really excited to see how everyone uses it! 🧵1/4

Watch Mark Williamson as he brings a zombie back to life by using Time Travel Debugging! youtube.com/watch?v=tjJLZ1… #Coding #Gamedev

Are you interested in learning how Doom works under the hood? Then try out Time Travel Debugging! youtube.com/watch?v=tjJLZ1… #Coding #Gamedev

Bugs whose effects travel across multiple processes? Fear no more!

The latest TTD release includes some pretty cool changes; you can now 'break on registers' (!tt br) & navigate to the next module boundary (!tt bm) and more! 🔥 learn.microsoft.com/en-us/windows-…

It's me!

In light of the recent news about DeepSeek AI, check out our new YouTube Video! How DeepSeek AI Works Under The Hood - Watch Replayed Program Execution with Time Travel Debugging youtube.com/watch?v=h-fJqX… #Coding #Openai #Programming

If you're writing C / C++ and you've not tried a modern time travel debugger then you're missing out.

There's also some good predictions for what I might do in future - maybe I can take those as a plan for the year!

Guilty!: hn-wrapped.kadoa.com/mark_undoio - Spends so much time talking about time travel debugging, [...] dreams in reverse chronological order - [...] used GDB more times than most people have used their smartphone

- Could write a PhD thesis on debugging [...] prints 'Hello World' when testing new languages

This is the American Radiator Building, a 101 year old black and gold skyscraper that's half Gothic, half Art Deco. It's famous, but not as famous as it should be — so here's a brief history of one of the world's coolest skyscrapers...

@culturaltutor The instant I saw the American Radiator building it became my favourite skyscraper in New York. I also go looking for it in Open World video games but am generally disappointed :-(

@Glaucous_Noise @ID_AA_Carmack Huh, I actually wouldn't have expected a substantial slowdown from the debugger on one of those - do you have any idea where the performance is lost? Is it also an unoptimised build?

@mark_undoio @ID_AA_Carmack C++ and FORTRAN, multi-threaded (and often debugging MPI as well)

I am always bemused by programmers that don’t use debuggers. It isn’t just about breakpoints and examining variables, but also being able to break into a process that has been running for an hour and issue something like: (observation_ring*255).to(dtype=torch.uint8).view(128,16,4,3,128,128).permute(1,0,2,4,5,3).cpu().numpy().tofile('results/ring_128x128.rgb')

@Glaucous_Noise @ID_AA_Carmack Ah, what language? Compiled language debuggers generally get pretty close to zero overhead because of how they're implemented - but other runtimes choose a different tradeoff. Ideally all languages would have a zero overhead debugger but it does create some challenges.

@mark_undoio @ID_AA_Carmack Debugger reduces performance, usually to the point it is unusable.

computer

@Andrath1975 @ID_AA_Carmack The annoying thing about "optimized out" is that it makes it harder to reason about some parts of the program - I think compilers don't always generate the quality of debug information to reason well about this stuff (but being able to inspect it at all is an improvement on not!)

The cool thing about debuggers is that you can see what the compiler optimized out, what variables contain, and what the stack looks like. You can single step up to a bug and see exactly what's screwing up. If you don't have anything else, "here" debugging is fine. But why settle for less?

@Lyle__Pro @ID_AA_Carmack You can use a time travel debugger to capture a recording, then get it back out of K8s and debug it offline.

@eeuoss @meow464_ @ID_AA_Carmack The Golang ecosystem has got this more right, I think - debug info built into binaries unless you opt out.

@eeuoss @meow464_ @ID_AA_Carmack Over time I've come to quite like the GDB command line interface - it's not perfect but actually the core command set is quite small and fairly consistent. But your point about building with -g is interesting - it's not even just the debugger, it's the whole ecosystem.