Tomorrow Corporation Tech Demo
Why Hacker News recommends it
Held up in debugger and tooling threads as an amazing ideal of a tight feedback loop and what debugging could be.
What it is
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.
Recommended by 5 HN commenters across 4 different months, 2023 to 2026.
What Hacker News said
Strong rec _gabe_ · 2023-03 · on “What a good debugger can do”
> I should mention that the perfect debugger doesn’t exist It may not exist, but this demo has got to be the closest thing to the perfect debugger I've ever seen: [this video]
Strong rec modernerd · 2024-04 · on “Leaving Rust gamedev after 3 years”
Allan Blomquist's tooling demo they mention is incredible, go watch it: [this video] Really sells the value of having a tight developer feedback loop: it shows hot reloading for code and graphics, a reversible debugger, live profiling with flame graphs, a data inspector with data breakpoints, time travel inspection with a scrub bar, session sharing and replay with the same scrub bar and direct links from the call stack to a breakpoint, and more. Above the many niggles they had with Rust itself, this greatly helps me understand why Rust left them wanting more from their working environment. They say they've switched back to Unity with [LINK] to try to capture some of that, and now I see why. (It's
Strong rec superdisk · 2026-01 · on “DDD was a great debugger – what would a modern equivalent look like today?”
This is a legitimate question but this was clearly generated using an LLM. To add something constructive, this demo represents an amazing ideal of what debugging could be: [this video]
Recommends Yoofie · 2023-03 · on “What a good debugger can do”
A whole world of creative opportunities open up when the toolchain and related debugging tools don't suck. Check out this wild video[1] of someone modifying and debugging a game in real time. [1]: [this video]
Recommends MikeSchurman · 2024-05 · on “GTFL – A Graphical Terminal for Common Lisp”
Yes, I'm a big fan of Bret Victor's work. I share his Inventing on Principle talk on a near yearly basis. I've seen light table years ago and thought it looked really neat, but I haven't looked into it much as it wasn't directly applicable to my environments. But, probably worth a look for ideas. On the topic of time-travel debugging, have you seen the demo: [this video] (Tomorrow Corporation Tech Demo) Very impressive, worth a watch.
Cites gwern · 2024-04 · on “Leaving Rust gamedev after 3 years”
He mentions Common Lisp as something he did a game in, and you can see the link he praises [this video] as basically a very well-developed Lisp image approach with timetravel debugging etc aimed at game dev. So the implicit comparison to Lisps is sort of a big undercurrent to this whole article.
Cites scrlk · 2026-08 · on “Show HN: C# Game Engine with its own scripting language and IDE”
Reminds me of the Tomorrow Corporation (developer of World of Goo) tech demo: [this video] Their entire stack is custom (language, compiler, IDE, build system, engine). Has neat features like time-travelling debugging and instant hot-reloading for code and assets.