diff --git a/.gitignore b/.gitignore
index c426c32..56b1232 100644
--- a/.gitignore
+++ b/.gitignore
@@ -33,4 +33,9 @@ out/
 /.nb-gradle/
 
 ### VS Code ###
-.vscode/
\ No newline at end of file
+.vscode/
+
+### Other ###
+development/run
+!development/run/eula.txt
+!development/run/server.properties
\ No newline at end of file
diff --git a/build.gradle.kts b/build.gradle.kts
index dcb005e..929a3dc 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -1,5 +1,5 @@
 plugins {
-    kotlin("jvm") version "1.9.0"
+    kotlin("jvm") version "1.9.20"
 
     id("maven-publish")
 }
@@ -18,7 +18,6 @@ repositories {
 
 dependencies {
     implementation(kotlin("stdlib"))
-
     compileOnly("io.papermc.paper:paper-api:1.19.4-R0.1-SNAPSHOT")
 }
 
diff --git a/development/build.gradle.kts b/development/build.gradle.kts
new file mode 100644
index 0000000..951205a
--- /dev/null
+++ b/development/build.gradle.kts
@@ -0,0 +1,45 @@
+import xyz.jpenilla.runpaper.task.RunServer
+
+plugins {
+    kotlin("jvm") version "1.9.20"
+    id("com.github.johnrengelman.shadow") version "8.1.1"
+
+    id("net.minecrell.plugin-yml.bukkit") version "0.5.3"
+    id("xyz.jpenilla.run-paper") version "2.1.0"
+}
+
+group = "me.tech"
+version = "1.0.0"
+
+repositories {
+    mavenCentral()
+
+    maven("https://papermc.io/repo/repository/maven-public/")
+}
+
+dependencies {
+    compileOnly("io.papermc.paper:paper-api:1.20.2-R0.1-SNAPSHOT")
+
+//    implementation("org.jetbrains.kotlin:kotlin-stdlib:1.9.20")
+    implementation(rootProject)
+}
+
+tasks.withType<RunServer> {
+    minecraftVersion("1.20.2")
+}
+
+java {
+    toolchain.languageVersion.set(JavaLanguageVersion.of(17))
+}
+
+bukkit {
+    name = "ui-development"
+    apiVersion = "1.20"
+    version = "${project.version}"
+    authors = listOf("Tech")
+    main = "me.tech.development.DevelopmentPlugin"
+
+    commands {
+        register("openui")
+    }
+}
\ No newline at end of file
diff --git a/development/run/eula.txt b/development/run/eula.txt
new file mode 100644
index 0000000..a9e07ce
--- /dev/null
+++ b/development/run/eula.txt
@@ -0,0 +1,3 @@
+#By changing the setting below to TRUE you are indicating your agreement to our EULA (https://aka.ms/MinecraftEULA).
+#Sat Nov 25 10:08:58 EST 2023
+eula=true
diff --git a/development/run/server.properties b/development/run/server.properties
new file mode 100644
index 0000000..21f2adf
--- /dev/null
+++ b/development/run/server.properties
@@ -0,0 +1,60 @@
+#Minecraft server properties
+#Sat Nov 25 10:27:18 EST 2023
+enable-jmx-monitoring=false
+rcon.port=25575
+level-seed=
+gamemode=survival
+enable-command-block=false
+enable-query=false
+generator-settings={}
+enforce-secure-profile=true
+level-name=world
+motd=A Minecraft Server
+query.port=25565
+pvp=true
+generate-structures=true
+max-chained-neighbor-updates=1000000
+difficulty=easy
+network-compression-threshold=256
+max-tick-time=60000
+require-resource-pack=false
+use-native-transport=true
+max-players=20
+online-mode=true
+enable-status=true
+allow-flight=false
+initial-disabled-packs=
+broadcast-rcon-to-ops=true
+view-distance=2
+server-ip=
+resource-pack-prompt=
+allow-nether=true
+server-port=25565
+enable-rcon=false
+sync-chunk-writes=true
+op-permission-level=4
+prevent-proxy-connections=false
+hide-online-players=false
+resource-pack=
+entity-broadcast-range-percentage=100
+simulation-distance=10
+rcon.password=
+player-idle-timeout=0
+debug=false
+force-gamemode=false
+rate-limit=0
+hardcore=false
+white-list=false
+broadcast-console-to-ops=true
+spawn-npcs=true
+spawn-animals=true
+log-ips=true
+function-permission-level=2
+initial-enabled-packs=vanilla
+level-type=minecraft\:normal
+text-filtering-config=
+spawn-monsters=true
+enforce-whitelist=false
+spawn-protection=16
+resource-pack-sha1=
+max-world-size=29999984
diff --git a/development/src/main/kotlin/me/tech/development/DevelopmentPlugin.kt b/development/src/main/kotlin/me/tech/development/DevelopmentPlugin.kt
new file mode 100644
index 0000000..60f05a0
--- /dev/null
+++ b/development/src/main/kotlin/me/tech/development/DevelopmentPlugin.kt
@@ -0,0 +1,42 @@
+package me.tech.development
+
+import me.tech.mcchestui.*
+import net.kyori.adventure.text.Component
+import org.bukkit.GameMode
+import org.bukkit.Material
+import org.bukkit.entity.Player
+import org.bukkit.event.EventHandler
+import org.bukkit.event.Listener
+import org.bukkit.event.player.PlayerJoinEvent
+import org.bukkit.plugin.java.JavaPlugin
+
+class DevelopmentPlugin : JavaPlugin(), Listener {
+    override fun onEnable() {
+        getCommand("openui")?.setExecutor { sender, _, _, _ ->
+            (sender as? Player)?.openGUI(open(sender))
+            true
+        }
+
+        // op & set gamemode on local server.
+        server.pluginManager.registerEvents(object : Listener {
+            @EventHandler
+            fun PlayerJoinEvent.on() {
+                player.gameMode = GameMode.CREATIVE
+                player.isOp = true
+            }
+        }, this)
+    }
+
+    private fun open(player: Player): GUI {
+        return gui(
+            this,
+            title = Component.text("Test UI"),
+            type = GUIType.Chest(rows = 3)
+        ) {
+            slot(1, 1) {
+                item = item(Material.CAKE)
+                onClick = { it.sendMessage("You've clicked the cake!") }
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/settings.gradle.kts b/settings.gradle.kts
index cac596b..480c2ca 100644
--- a/settings.gradle.kts
+++ b/settings.gradle.kts
@@ -1 +1,3 @@
-rootProject.name = "mc-chestui-plus"
\ No newline at end of file
+rootProject.name = "mc-chestui-plus"
+
+include("development")
\ No newline at end of file