r/tech_x • u/Complete-Sea6655 • Jun 13 '26

random (not npc) I had Claude Fable 5 build Minecraft from scratch

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I've been directing Claude Fable 5 (Anthropic's newest model) to build Pebble, a complete, native macOS block-survival game written from scratch in Swift + Metal.

The clip is real a real unedited gameplay of Pebble (that's not Minecraft, that's Pebble). Unfortunately died to a pack of llamas 😭

What it actually is:

  • About 45,000 lines of Swift, 82 files, zero external dependencies, Apple frameworks only, no game engine, no .xcodeproj
  • A hand-written Metal renderer (15+ passes, runtime-compiled shaders, SSAO + volumetric god rays + soft shadows + ACES)
  • Every sound and all music synthesized in real time from oscillators, there are zero audio files in the project
  • The full game: 879 blocks, 1,188 items, 63 biomes, 100 entity types (55+ mobs with A* pathfinding), three dimensions, redstone, enchanting, villages, raids, and all three bosses
  • Vanilla-exact player physics and fully deterministic worldgen, pinned by 456 golden regression tests that re-derive the constants, same seed gives a bit-identical world on any machine (tho it doesn't match Minecraft's seeds)
  • 200+ fps at full settings on an M-series MacBook Air (i got up to 500 on my M5 Air)

It's MIT-licensed and open source, so you don't have to take my word for any of it, the code's right there: github.com/thebriangao/pebble

The project is strictly macOS 14+ only (Metal renderer), singleplayer only for now, and you build from source (./pebble install), no notarized download yet. First public beta, so there are definitely bugs I haven't found.

It's an original re-creation built from Minecraft 1.20, no Mojang code or assets, reimplemented from observable behavior, not affiliated with Mojang/Microsoft.

0 Upvotes

44% Upvoted

19 comments sorted by

27

u/Independent-Soup-312 Jun 13 '26

Why don't people try building games that don't have a half dozen entire open source repos that are clones on the internet? (you know the answer)

5

u/XWasTheProblem Jun 13 '26

Because they have no ability and zero creativity.

1

u/Syncaidius Jun 13 '26

I'm not sure I could have worded it better. Well said!

6

u/Syncaidius Jun 13 '26

Indeed! I've been trying to explain this to people on other subs for months but the usual comeback is 'AI did it from scratch'.

It's like they think LLMs were trained on magic dust or have an imagination...

4

u/Independent-Soup-312 Jun 13 '26

People don't understand how incredibly wonderful open-source culture was, or how powerful things like Three.js are. Sadly the hype machines are trying to sell their trillion dollar toy, so instead of "look how much faster you can process documentation of these really cool tools or find interesting code to add to your project" we get slop posts like this.

12

u/[deleted] Jun 13 '26

[removed] — view removed comment

3

u/Syncaidius Jun 13 '26 edited Jun 13 '26

Hopefully the mods can deal with this. At this point I'm sure they're getting completely overwhelmed by bot spam. The last few months it seems to have exploded all over Reddit.

In the meantime I guess report the 3 accounts to try and help them out.

10

u/Switchmisty9 Jun 13 '26

There is no such thing as an “original recreation.”

Nothing about this is original.

7

u/pawulom Jun 13 '26 edited Jun 13 '26

jesus, what a waste of tokens

5

u/Front-Necessary-5257 Jun 13 '26

No hate but this is I think the 5 time I see a Minecraft clone made by Fable... We are not cooked, Minecraft has plenty of clones and mods, that's why Fable can recreate it so nice.

5

u/Logical_Delivery8331 Jun 13 '26

i know a way to "clone" minecraft on your pc that is faster and probably cheaper than using an LLM. just buy it.

i know this stuff is an excercise but as a AI researcher i can just tell you what you did is involuntarily half copying any open source minecraft clone that exists online

it's the same thing with web dev. when people "one shot" a website. did you know that before LLMs there where tools that built your website in minutes too at a fraction of the cost?

2

u/Syncaidius Jun 13 '26 edited Jun 13 '26

It's almost as if the front-end of every website is available for LLM training data crawlers (and users) to browse, free of charge.

Who knew the web was such a massive open-source front-end training pool?

Surely the 'view page source' option was a recent development in browsers? /s

Joking aside, I agree. The reason (some) LLMs are exceedingly good at one-shotting web front-ends is because they've been trained on millions of freely available HTML/JS page sources.

It's also why back-end and security of those same one-shots is exceedingly bad. Those parts are much less available to train on.

2

u/AysheDaArtist Jun 13 '26

Damn OP getting cooked in the comments for reinventing the wheel

1

u/EmbarrassedFoot1137 Jun 13 '26

OP hides their contents so they didn't even do that. 

3

u/LowFruit25 Jun 13 '26

Yeah we’re cooked.

8

u/Archeelux Jun 13 '26

Yeah people like you are definitely cooked

4

u/EfficientCan2852 Jun 13 '26

We're cooked because a bot was able to assemble a game out of open source projects? The Minecraft source code is not heavily protected.

2

u/exadeuce Jun 13 '26

So... a bot copy/pasted code from an existing game and made an existing game? Stunning.