diff --git a/config.d.ts b/config.d.ts
index 8960a80..7d9cfce 100644
--- a/config.d.ts
+++ b/config.d.ts
@@ -9,6 +9,18 @@ export interface Config {
 		name?: string
 		description?: string
 		version?: [number, number, number]
+
+		metadata?: {
+			authors?: string[]
+			license?: string
+			url?: string
+		}
+
+		subpacks?: {
+			folder_name?: string
+			name?: string
+			memory_performance_tier?: number
+		}[]
 	}
 	global_variables?: Record<Variable, string>
 }
diff --git a/package.json b/package.json
index 18977be..6aceaa5 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
 	"name": "asajs",
-	"version": "4.0.0-indev-2",
+	"version": "4.0.0-indev-3",
 	"description": "Create your Minecraft JSON-UI resource packs using JavaScript",
 	"keywords": [
 		"Minecraft",
diff --git a/resources/asajs.config.cjs b/resources/asajs.config.cjs
index 7e4026f..61c33d7 100644
--- a/resources/asajs.config.cjs
+++ b/resources/asajs.config.cjs
@@ -3,7 +3,12 @@
  * @type {import('asajs/config.d.ts').Config}
  */
 export const config = {
+	packinfo: {
+		name: "AsaJS",
+		description: "Create your Minecraft JSON-UI resource packs using JavaScript.",
+	},
 	compiler: {
 		enabled: true,
+		linked: false,
 	},
 }
diff --git a/src/compilers/Configuration.ts b/src/compilers/Configuration.ts
index f34c6ca..758a087 100644
--- a/src/compilers/Configuration.ts
+++ b/src/compilers/Configuration.ts
@@ -7,6 +7,10 @@ if (!fs.existsSync("asajs.config.cjs")) {
 	fs.copyFileSync("node_modules/asajs/resources/asajs.config.cjs", "asajs.config.cjs")
 }
 
+if (!fs.existsSync(".gitignore")) {
+	fs.writeFileSync(".gitignore", `node_modules`, "utf-8")
+}
+
 export const config: Config = require(path.resolve(process.cwd(), "asajs.config.cjs")).config
 
 export let isBuildMode = config.compiler?.enabled ?? false
diff --git a/src/compilers/ui/builder.ts b/src/compilers/ui/builder.ts
index 1343fa2..a4d4acc 100644
--- a/src/compilers/ui/builder.ts
+++ b/src/compilers/ui/builder.ts
@@ -5,6 +5,7 @@ import { genManifest } from "./manifest.js"
 import { UI } from "../../components/UI.js"
 import { Type } from "../../types/enums/Type.js"
 import fs from "fs/promises"
+import { BuildCache } from "./buildcache.js"
 
 async function buildUI() {
 	const build = Memory.build()
@@ -15,10 +16,6 @@ async function buildUI() {
 
 	if (config.global_variables) build.set("ui/_global_variables.json", config.global_variables)
 
-	build.set("build.json", {
-		files: Array.from(build.keys()),
-	})
-
 	const out = await Promise.all(
 		build.entries().map(async ([file, value]) => {
 			const outFile = `build/${file}`
@@ -46,6 +43,7 @@ async function buildUI() {
 	await Promise.all([
 		fs.writeFile("build/manifest.json", await genManifest(), "utf-8"),
 		fs.writeFile("build/.gitignore", [...out, "manifest.json"].join("\n"), "utf-8"),
+		BuildCache.set("build-files", [...out, "manifest.json"]),
 		fs
 			.stat("build/pack_icon.png")
 			.catch(() => fs.copyFile("node_modules/asajs/resources/pack_icon.png", "build/pack_icon.png")),
diff --git a/src/compilers/ui/linker.ts b/src/compilers/ui/linker.ts
index ca33802..dfba894 100644
--- a/src/compilers/ui/linker.ts
+++ b/src/compilers/ui/linker.ts
@@ -1,7 +1,6 @@
 import fs from "fs/promises"
 import { BuildCache } from "./buildcache.js"
 import { RandomString } from "../../components/Utils.js"
-import { prevData } from "./prevdata.js"
 import path from "path"
 import { getGamedataPath } from "./installer.js"
 
@@ -25,7 +24,8 @@ function genUUID(): string {
 }
 
 export async function clearBuild() {
-	await Promise.all(prevData.files.map(file => fs.rm(`build/${file}`).catch(() => null)))
+	const files: string[] = (await BuildCache.get("build-files")) || []
+	await Promise.all(files.map(file => fs.rm(`build/${file}`).catch(() => null)))
 }
 
 export async function createBuildFolder() {
diff --git a/src/compilers/ui/manifest.ts b/src/compilers/ui/manifest.ts
index 7b22595..f80653e 100644
--- a/src/compilers/ui/manifest.ts
+++ b/src/compilers/ui/manifest.ts
@@ -7,10 +7,11 @@ export async function genManifest() {
 		format_version: 2,
 		header: {
 			name: config.packinfo?.name || "AsaJS",
-			description: config.packinfo?.description || "A framework for creating UIs for AsaJS.",
+			description:
+				config.packinfo?.description || "Create your Minecraft JSON-UI resource packs using JavaScript.",
 			uuid: uuid1,
 			version: config.packinfo?.version || [4, 0, 0],
-			min_engine_version: [1, 21, 132],
+			min_engine_version: [1, 21, 80],
 		},
 		modules: [
 			{
@@ -20,5 +21,7 @@ export async function genManifest() {
 				version: [4, 0, 0],
 			},
 		],
+		subpacks: config.packinfo?.subpacks,
+		metadata: config.packinfo?.metadata,
 	})
 }
diff --git a/src/compilers/ui/prevdata.ts b/src/compilers/ui/prevdata.ts
deleted file mode 100644
index 1d34dfe..0000000
--- a/src/compilers/ui/prevdata.ts
+++ /dev/null
@@ -1,11 +0,0 @@
-import fs from "fs"
-
-export let prevData: {
-	files: string[]
-}
-
-try {
-	prevData = JSON.parse(fs.readFileSync("build/build.json", "utf-8"))
-} catch (error) {
-	prevData = { files: [] }
-}
diff --git a/src/components/Utils.ts b/src/components/Utils.ts
index 42920e6..bbf3e16 100644
--- a/src/components/Utils.ts
+++ b/src/components/Utils.ts
@@ -144,6 +144,12 @@ export function Modify<T extends Namespace, K extends Element<T>>(namespace: T,
 	const memoryUI = MemoryModify[paths[namespace][name]]?.[name]
 	// @ts-ignore
 	if (memoryUI) return memoryUI as ModifyUI<VanillaType<T, K>, VanillaElementChilds<T, K>>
+	if (!paths[namespace]) {
+		throw new Error(`Namespace '${namespace}' does not exist`)
+		// @ts-ignore
+	} else if (!paths[namespace][name]) {
+		throw new Error(`Element '${name}' does not exist in namespace '${namespace}'`)
+	}
 	// @ts-ignore
 	const modifyUI = new ModifyUI<VanillaType<T, K>, VanillaElementChilds<T, K>>(
 		namespace,