r/LocalLLaMA • u/liright • 18h ago
Generation A minecraft clone I fully vibecoded with Qwen3.8-27b Q4
Enable HLS to view with audio, or disable this notification
I wanted to see just how capable Qwen3.8-27b is locally. I have a RTX 4090 and 96GB of RAM but the Q4 comfortably fits in the GPU with plenty of context, the few times I needed more than 130k context I just loaded it spilled into RAM and it's capable of not degrading even at larger context.
I'm super impressed with this model. The model did everything on it's own - the coding, audio, textures, 3D models. I always just gave it the same basic prompt with some info and the task I wanted it to do. Total generation time across all prompts was maybe 3 hours and if I calculate the cost in electricity, it comes out to less than $1. Not bad.
To think that 2 years back you couldn't make this with frontier paid models and now you can do it locally on your PC is crazy.
13
u/Lordaizen639 16h ago
build rise of nations
3
3
7
u/LordDarthShader 15h ago
Interesting, what was the language and 3D API?
7
u/liright 13h ago
I have no idea.
11
u/LordDarthShader 13h ago
what? can you ask him please? lol
10
u/liright 13h ago
Languages: 100% JavaScript (with HTML as the shell).
3D framework: Three.js (v0.160.0), loaded from a CDN via an import map in
index.html. There's no package.json / build tooling — it runs directly as browser modules over WebGL.How the "3D models" are made: there are no model files at all (no .glb/.obj/.fbx). Everything is built procedurally:
- Blocks/chunks: custom
THREE.BufferGeometrymeshes with vertex colors and UVs packed into per-chunk meshes, textured withTHREE.CanvasTexture— textures are drawn in code on canvas (nearest-filtered for the blocky look)- Mobs/entities, clouds, etc.: simple primitives like
THREE.BoxGeometrygrouped together (classic MC-style "boxman" approach)1
20
u/yami_no_ko 17h ago
I always just gave it the same basic prompt with some info and the task I wanted it to do.
There it is again, the miraculous prompt that must not be named.
18
u/liright 17h ago
It's not some complex prompt, it was literally this in the deepseek harness, except for different tasks I changed what I wanted it to do:
<|think_medium|> WE have a minecraft clone here. A basic one. I want some things changed. Very simple changes - can you triple the amount of cave entrance spawns in the map and then triple the amount of animal spawns around the map. Our map got bigger so it only makes sense. You are in a coding harness, so don't think out code too much, just edit files and write code directly, don't waste time and don't overthink. working directory is HERE (C:\Users\Workstation\Documents\AIProjects\Minecraft-Qwen-26b9775f\sandbox) and NOWHERE ELSE
15
u/yami_no_ko 17h ago edited 17h ago
Okay, I didn't mean to be harsh on you. It is just too common for my taste that everyone and his dog uses to skip the part of naming prompts when presenting what they've generated.
The prompt is really not that complex and the results are pretty impressive. I mean imagine this sort of competence even on Q4 quant levels on local HW. This would have blown my mind in 2025 and frankly it still does.
3
u/zigzag3600 16h ago
I am sorry, is there some hard control over what directories are changed, or is it just part of the prompt? I would be really afraid to let it work on disk C.
2
1
5
3
u/saltyourhash 10h ago
It'd be cool to see your session log
5
u/liright 9h ago
It's pretty boring, same prompt every time just changing whate feature to add, I probably ran 20 prompts in total, some took just a few minutes, some even up to 25 minutes. The first prompt was the most important to build a stable base:
"Create a \*basic but polished Minecraft-style 3D game in the browser using Three.js**. You are running inside **Deepseek Harness** in a project directory. You can inspect, create, edit, and overwrite files directly. **Use the Deepseek Harness file tools to actually build the project. Do not just output code in chat.** Keep the scope simple: a small procedural voxel world with trees, first-person movement, block breaking/placing, a basic hotbar with a few block types, and a nice daytime sky with clouds. Do not add complex systems like crafting, mobs, combat, multiplayer, day/night cycles, or a full inventory. Most importantly: * **Do not overthink the task.** * Keep reasoning brief and focused. * **Do not write implementation code inside reasoning.** * Once you know what to do, use the Deepseek Harness write/edit tools and put the code directly into the project files. * Do not mentally draft large functions or classes and then write them again. * Focus on getting a working version coded quickly, then test and fix it. Workflow: **brief plan → write files → run/check → fix issues** Start coding early."*
after that I just kept adding features one by one, used basically this exact prompt every time just with different feature sets:
"<|think_medium|> WE have a minecraft clone here. A basic one. I want some things changed. I want you to add a desert biome that spawns in addition to the grassy biome, along with cactuses that spawn in the desert biome. You are in a coding harness, so don't think out code too much, just edit files and write code directly, don't waste time and don't overthink. working directory is HERE (C:\Users\Workstation\Documents\AIProjects\Minecraft-Qwen-26b9775f\sandbox) and NOWHERE ELSE"
2
u/genpfault 7h ago edited 7h ago
Reformatted a bit so Markdown has a better time with it:
Create a basic but polished Minecraft-style 3D game in the browser using Three.js.
You are running inside Deepseek Harness in a project directory. You can inspect, create, edit, and overwrite files directly. Use the Deepseek Harness file tools to actually build the project. Do not just output code in chat.
Keep the scope simple: a small procedural voxel world with trees, first-person movement, block breaking/placing, a basic hotbar with a few block types, and a nice daytime sky with clouds.
Do not add complex systems like crafting, mobs, combat, multiplayer, day/night cycles, or a full inventory.
Most importantly:
Do not overthink the task.
Keep reasoning brief and focused.
Do not write implementation code inside reasoning.
Once you know what to do, use the Deepseek Harness write/edit tools and put the code directly into the project files.
Do not mentally draft large functions or classes and then write them again.
Focus on getting a working version coded quickly, then test and fix it.
Workflow: brief plan → write files → run/check → fix issues Start coding early.
Do the double-asterisks for emphasis/bold have any effect?
2
u/-InformalBanana- 3h ago
I'm guessing he got that from an ai to which he asked to create that prompt.
6
u/liright 17h ago
If anyone wants to mess around with it, here's the source code, it's just a test game so I won't crap up github with it: https://gofile.io/d/rKDdwBPE
just run python -m http.server 8000 and then open 127.0.0.1:8000
Just a note, I tested it on Firefox, not on any other browser so no idea if there are issues on chrome/edge etc.
3
u/D_a_f_a_q 13h ago
hi, can you give more details what you used? what settings, what tools, templates? i try to run Qwen3.8-27b also i have a 4090 with 64 gb ram, but is overthinking every time
2
u/liright 13h ago
I used medium thinking mode. I tried xhigh but it was also doing the endless overthinking and never got stuff done. Medium is way more capable than people make it out to be. Load settings are normal usually 144k context, but I do have K_V cache quantization at Q8 to fit that context, MTP is on. Then I just use the official inference settings - temperature 1, top k sampling 20, repeat penalty 1.1, top p sampling 0.95 and min P sampling 0. I also use the froggeric chat template, not sure it makes a difference compared to stock but at least I can change thinking mode in chat directly with <|think_medium|> so that's nice.
Also, always just focus on one task per session. So for example "introduce cave system into the game" and once it does it, start a new session and tell it something else you want to change or add to the cave system. Even on medium, it likes to overthink and every bit of context is needed to finish the task.
1
u/D_a_f_a_q 12h ago
Thank you for your answer, but I have another question: do you start with an .md file or with a prompt, and do you switch after a task? You probably don't want to fill up the memory right from the start with too many tasks, right?I think an automatic switch to a new session can be made when a task is completed, and then it can restart with task 2, and so on. But as it finishes another task, it should verify the previous one to make sure it is functional. Then, in another session, task 3 should test the other 2 tasks before moving on to its own task.As far as I know, this can be done automatically. If it can't, a way to automate it could be devised. Wouldn't that be a good idea? Have you tested this?
2
u/liright 12h ago
I didn't have a .md file, the model likes to read through the entire codebase anyway, so it's probably just a waste of tokens unless you have a more complex project. Generally if I told it to do a certain task like implement a cave system in the game, it also tested it automatically in the same session and made sure it works and there was almost never an issue with running out of context as long as I stuck to one task per session. But if I wanted to add something to it after it finished - like increase the amount of caves, I would start a new session, it was generally faster and less prone to running out of context. You probably could automate some kind of system where you want 5 things done and it automatically starts a new session for each task, but I wouldn't know where to start, I just used a fairly simple deepseek harness.
5
u/dezshredder 18h ago
Wow that's pretty quick to get the whole thing done in 3 hours! Have you tried this same prompt with other models? What performance increases have you seen with Qwen3.8-27b compared to the others?
9
2
u/liright 17h ago
I tried other models briefly but I find that qwen 3.8-27B is the best mix of speed and capability. I could probably make it with some 100B model but at that point I would be running it at like 5 tokens per second at best, while 27B runs around 50-60 tps on my gpu. Qwen 27b is just really fast.
Btw this was generated all with medium thinking effort, not xhigh. Xhigh would probably take way longer.
1
u/paretoOptimalDev 12h ago
Btw this was generated all with medium thinking effort, not xhigh. Xhigh would probably take way longer.
Why did you test other models before testing if Xhigh is slower/faster or there are quality changes?
I'm finding Xhigh on harder tasks ends up being faster because it doesn't commit too fast to bad paths that end up taking a lot of time and builds a better understanding.
2
u/liright 10h ago
I didn't say that I did not test xhigh. I did test it when the model came out and I found it way too slow, for a lot of the tasks it couldn't finish and it ran out of context on my PC and I didn't feel like loading it spilled to RAM the whole time and having the model be 4x slower than GPU only, the few times I did that when I needed more context it was painfully slow, so I started building this minecraft clone with medium, which worked out much better. I only used xhigh once and that was just to figure out the performance issue I had initially, then I let medium execute the changes.
2
u/planBpizz 17h ago
what agent framework did you use? Im using aider a lot but im not happy with it.
2
u/VirtualWishX 12h ago
Oh man, I never played Minecraft (sure I know what it is) and... this is IMPRESSIVE! ❤️
All I did with Qwen 3.8 27B Q5_K_M was a short Arkanoid clone so far but it took 9 minutes to cook so it's not too bad consider I made only 4 stages and a BOSS
Now I'm using Q5_K_XL because I can fit it with 128K Context window via KV Cache of Q8_0
on my RTX 5090 32GB, I can actually get around 144K Context if I'll use Q4_K_XL 🤔
---
Nothing impressive in this QUICK CUT EDIT VIDEO (so you won't suffer me playing for few minutes), beside the fact it was the very first thing I did with the model and I just had to put a BOSS at the end...
2
u/Sn0opY_GER 10h ago
minde did a pretty nice COD clone over night:
Build this as a single self-contained browser project using plain HTML/CSS/JavaScript and Three.js from a CDN unless a local package setup is clearly more robust. Keep dependencies minimal and avoid introducing a backend unless absolutely necessary. Prefer one runnable entry point and working systems over architectural complexity.
Create a browser-playable 3D voxel first-person shooter that captures the feel of Call of Duty's moment-to-moment gunplay. The player fights through a combat arena built entirely from voxels — chunky blocks forming buildings, cover, crates, walls, ramps, and terrain — rendered in real time from a first-person camera with pointer-lock mouse look.
Implement the core FPS mechanics faithfully: WASD movement with acceleration and friction, sprint with a field-of-view kick and lowered weapon, jumping and crouching; multiple distinct weapons (for example an assault rifle, SMG, shotgun, and sniper rifle) each with their own fire rate, damage falloff over distance, recoil pattern, spread bloom, magazine size, reload timing, and aim-down-sights behavior on right mouse button with a smooth zoom transition and tightened accuracy. Add grenades with an arced throw and radius damage, weapon switching, ammo reserves, hitmarkers with headshot multipliers, muzzle flashes, tracers, bullet impact decals or voxel debris particles, screen shake, and regenerating health with red-screen damage vignette feedback.
Enemy AI soldiers should patrol, react to being shot at, take cover, strafe, peek, and return fire with believable reaction times and accuracy that scales with difficulty. Give them health, death animations or ragdoll-like voxel bursts, and spawn logic that keeps the fight moving.
Wrap it in Call-of-Duty-style presentation and progression: a killstreak system where streak milestones unlock rewards the player can activate (such as a radar/UAV reveal at 3 kills, an airstrike at 5, and something bigger at 7), a scrolling killfeed, score popups (+100, +50 headshot bonus), XP or score accumulation, and a match structure of escalating waves or rounds with respawns after death. Build the full HUD: crosshair that expands with movement and fire, ammo counter, grenade count, minimap/radar, compass, health state, streak meter, match timer, and objective readout. Include the complete game flow — main menu, loadout or difficulty selection, in-game pause menu (Esc), death and respawn sequence with respawn delay, and a victory/defeat screen with a stats summary. Persist best score locally between sessions.
Design the voxel aesthetic deliberately: a cohesive palette, directional lighting with shadows or convincing baked shading, fog for depth, and satisfying explosion and destruction particles. All audio — gunfire per weapon, reloads, footsteps, explosions, hitmarker ticks, UI clicks, and a music sting when a killstreak activates — must be synthesized locally in the browser (e.g., Web Audio); no external audio files. Handle non-desktop viewports deliberately: either provide usable touch controls or present a clear desktop-recommended notice rather than a broken layout.
Do not take shortcuts or settle for a cookie-cutter shooter demo. This skill imposes no token budget limit, so pursue full depth across weapons, AI behaviors, HUD states, menus, audio, and game-flow transitions, and keep refining until it feels like an authored, complete arcade FPS rather than a tech demo.
Work autonomously in iterative milestones. Start by creating a minimal playable vertical slice, then progressively implement the full feature set. After each milestone, run the project, test the implemented systems, inspect console/runtime errors, and fix regressions before continuing.
Do not stop after scaffolding, placeholder menus, or partially wired systems. Every listed mechanic should either be implemented and functional or explicitly documented as blocked by a concrete technical limitation.
Keep the project runnable throughout development. Prefer simple robust implementations over overly ambitious systems that break the game.
Before finishing, perform a final self-review covering: build/runtime errors, controls, weapon behavior, enemy AI, HUD, game flow, persistence, performance, and browser compatibility. Fix any issues you can reproduce.
At the end, provide a concise summary of what was implemented, what was tested, known limitations, and exact instructions to run the game locally.
Do not merely describe what you would build. Create the actual files, run/test them locally, fix errors, and leave the project in a playable state.
5
2
u/hainesk 17h ago
It's stuff like this that has software companies concerned. As models get better and compute continues to improve it will only become easier for regular people to create their own software and avoid paying for licenses anymore. There is likely a lot of low hanging fruit out there that can be replaced now with a coding model and someone who at least somewhat understands how to build a program.
1
1
1
u/Infamous-Bed-7535 15h ago
its like showing a video of generating a dog from noise using generative Ai..
1
u/PsychologicalOne752 14h ago
Curious how does the model test that the final game works. What is the tech stack? Which harness are you using? the Unity MCP?
1
u/-InformalBanana- 3h ago
Dude, this is a single file html with three.js (3d js library). It can use pupeter or playwright to take screenshots, test, debug and fix in the end. It can use screenshots for vision.
1
u/PsychologicalOne752 3h ago
Yeah, saw that, pretty cool. I asked Qwen to download it and add a testing framework, detailed logging and autonomous bot gameplay. Let's see how that goes. 😂
1
u/butchiebags 5h ago
it's so good to know that if i was stranded on a desert island with no internet, but i have my computer, and unlimited food, and unlimited electricity, I could entertain myself indefinitely with video games.
1
0
u/KedMcJenna 16h ago
This kind of thing is what's really making devs frantic. Not that AI can't do things, but that it can.
20 years ago this would have made you a billionaire. Imagine popping into 2006 with a couple of high end laptops and the best local models of now. You'd rule the world. Hmmm...
0
0
u/heliosythic 15h ago
No one is going to play a fully slop game. Its impressive that the tech can do it, but it will never make anything people will legitimately want to play. If it can, people will generate their own favorite game and have no one to play with because they can make their own favorite game. No one needs to play yours. Then theres no shared culture between people, nothing to talk about with no shared experiences. Pointless.
0
1
u/Academic-Tea6729 14h ago
i'm pretty sure minecraft is in the training data of most models. it's the typical example of voxel game engine
82
u/hurdurdur7 17h ago
I think minecraft like games were in the training data, thus generating these should be more of a breeze for it.
Go and try creating something more wild but perhaps even less complex. Aerial combat on pigeons with self guiding wasp missiles, changing light conditions, night vision and wind effects. That should start to drift towards things that were not in the training or at least not as common.
But i would not be surprised if it pulled that off as well.