SmokeyStack

The .brpak format: Minecraft Bedrock's unshipped "baked pack" container

Status: latent / unshipped. As of Minecraft Bedrock Preview 1.26.50.26 (August 2026), no .brpak file has ever been observed on disk — not in the game payload, not in BDS, not in any local cache. Everything below is datamined from reader/writer code that already exists inside bedrock_server.exe. Treat the "format" section as verified-by-error-strings and the "purpose" section as informed inference.

TL;DR

.brpak is a pack-level container format that Mojang has built but not yet turned on. It is a plain ZIP file whose archive comment must begin with BRPAK/, whose entries must all be STORE (uncompressed), and which is validated strictly enough to safely load untrusted third-party packs. It is produced by an internal BakeTool that "bakes" a pack folder: upgrading its documents to the current format version, compiling them (Cereal/MCB), bundling them into a .brarchive, and wrapping the whole pack into

SmokeyStack

Sourced from @veka. from the Bedrock Add-Ons discord.

Ok so here are the facts:

1. Material format was changed multiple times in previous previews - they added new properties which aren't being used anywhere in vanilla. Why would they add them and never use? And one of the added unused properties allows to overwrite texture properties through materials that are usually supplied by the game directly, why would they add that overwrite property to materials if they can (and always do) just set it from the game directly?
2. Some time ago, a new function appeared in shader source code

struct StandardSurfaceOutput {
    vec3 Albedo;
    float Alpha;
 float Metallic;

SmokeyStack

[
	
	{
		"pack_id" : "985d1ee4-0e9d-49de-9a99-e208adc08d0c",
		"version" : [ 1, 0, 0 ]
	}
]

SmokeyStack

minecraft:acacia_button
minecraft:acacia_door
minecraft:acacia_fence_gate
minecraft:acacia_pressure_plate
minecraft:acacia_stairs
minecraft:acacia_standing_sign
minecraft:acacia_trapdoor
minecraft:acacia_wall_sign
minecraft:activator_rail
minecraft:air

SmokeyStack

Glare:
Pros:
  - One of the F3 functionality in mob farm. Useful for Bedrock players.
  - Can be used in lush cave builds due to its similarity to an azalea bush.
  - Maybe useful for finding caves?
Cons:
  - Counting: exists.
  - If you accidently lead it into your mob farm, it's going to be a hassle to take it out.
  
Allay:

SmokeyStack

from pathlib import Path
import json
import os
identifier = input("Identifier:")
displayName = input("Display Name:")
cooldownDur = float(input("Cooldown Duration:"))

itemID = identifier.split(":", 2)
mainPath = 'output'
Path(mainPath).mkdir(parents=True, exist_ok=True)