NBT to Data API

Small library mod for developers, which adds the ability to use the old NBT format, as well as conveniently edit

NBT to Data API πŸ›‘οΈπŸ“¦

A lightweight, developer-friendly Kotlin DSL and SNBT translation library for Minecraft mod developers.

This API provides a unified way to edit ItemStack data, automatically handling the architectural gap between legacy NBT-tag versions and the modern Data Component system.


⚠️ Project Status: Alpha

This project is currently in its Alpha stage. The core APIs are stable and optimized, but breaking changes may occur as we continue to refine platform compatibility. Use with care in production environments.


πŸ—ΊοΈ Supported Versions

  • Branch 1.20: Supports Minecraft 1.20 to 1.20.4 (Fabric & Forge).
  • Branch 1.21: Supports Minecraft 1.21 to 1.21.1 (Fabric & NeoForge).

πŸ“¦ How to include NBT to Data API in your Gradle project

Add the Modrinth Maven repository to your root build.gradle (or settings.gradle):

repositories {
    maven {
        name = "Modrinth"
        url = "https://api.modrinth.com/maven"
    }
}

Then, add the dependency to your project modules:

For Multi-Loader (Architectury) Projects:

If you are developing a multi-loader mod, use modCompileOnly in your common project to prevent Loom from throwing loader-validation errors due to merged platform files, and use modImplementation in your loader-specific projects (fabric, forge, neoforge) to load it at runtime:

  • In common/build.gradle: gradle dependencies { // Compile-only on the clean API classpath modCompileOnly "maven.modrinth:nbttodata:0.1.0-alpha-${minecraft_version}" }
  • In fabric/build.gradle and forge/build.gradle: gradle dependencies { // Load the mod at runtime on specific platforms modImplementation "maven.modrinth:nbttodata:0.1.0-alpha-${minecraft_version}" }

For Single-Loader Projects (Fabric / Forge / NeoForge only):

If you are building a standalone mod for just one loader, simply use modImplementation directly in your build.gradle:

dependencies {
    modImplementation "maven.modrinth:nbttodata:0.1.0-alpha-${minecraft_version}"
}

πŸš€ Features

1. editData β€” Unified Kotlin DSL Builder

Provides a clean, declarative Kotlin DSL to edit item stack properties. The builder syntax remains identical across all supported Minecraft versions, translating your code to raw NBT tags on 1.20.x, and to Data Components on 1.21.x under the hood.

Here is a comprehensive example demonstrating every available builder tag in action:

item.editData {
    // Basic Properties
    damage = 100
    customModelData = 12345
    unbreakable = true
    mapId = 42
    fireworkFlight = 3

    // Tooltip Hide Flags
    hideEnchantments = true
    hideAttributes = true
    hideUnbreakable = true
    hideAdditionalTooltip = true

    // Unified Enchantments (automatically maps to StoredEnchantments on books!)
    enchantments {
        "minecraft:sharpness"(5)
        "minecraft:fire_aspect"(2)
        -"minecraft:fire_aspect" // Easily remove any enchantment by ID
    }

    // Display Name and Lore
    display {
        setName("Doom Artifact", color = "dark_red", italic = true)
        +"A mysterious sword forged in the nether." // Add lore line via "+"
        +"It glows with unholy energy..."
    }

    // Player Skull Properties
    skull {
        name = "aleksti21"
        textureBase64 = "eyJ0ZXh0dXJlcyI6eyJTS0lOIjp7InVybCI6Imh0dHA6Ly90ZXh0dXJlcy5taW5lY3JhZnQubmV0L3RleHR1cmUvM2I5M2Zl..."
    }

    // Custom Food Properties
    food {
        nutrition = 6
        saturation = 0.8f
        canAlwaysEat = true
        eatSeconds = 2.0f
        convertsTo = "minecraft:bowl" // Item left in hand after eating
        effects.add(FoodEffectData("minecraft:regeneration", 100, 1, 1.0f))
    }

    // Banner Pattern Layers
    banner {
        "stripe_top"(DyeColor.RED)
        "base"(DyeColor.BLUE)
    }

    // Written / Writable Book Data (pages are automatically mapped)
    book {
        title = "The Ancient Scroll"
        author = "Alex"
        generation = 0
        resolved = true
        +"Page 1: The journey begins..."
        +"Page 2: The end of NBT is near."
    }

    // Attribute Modifiers
    attributes {
        "minecraft:generic.attack_damage"(10.0, modifierName = "artifact_boost")
    }

    // Adventure Predicates (Accepts varargs of block IDs)
    canDestroy("minecraft:stone", "minecraft:iron_ore")
    canPlaceOn("minecraft:obsidian")

    // Custom Potions
    potion {
        id = "minecraft:strong_healing"
        customColor = 16711680 // Custom RGB color
    }

    // Container Inventory (Slot operators supported!)
    inventory {
        0(ItemStack(Items.DIAMOND, 64)) // Place 64 diamonds in slot 0
        1(ItemStack(Items.GOLD_INGOT, 32))
        !1 // Remove items from slot 1 using "!"
    }

    // Direct Block Entity Tag Editing
    blockEntityData {
        putString("CustomSpawnerTag", "MyValue")
    }

    // Direct Custom NBT Data Editing
    customData {
        putBoolean("MySecretModFlag", true)
    }
}

2. applySNBT β€” Legacy SNBT Translation

Allows you to feed legacy SNBT (String NBT) strings directly into an ItemStack. The API parses, cleans, and translates the data. It maps it directly to raw NBT on 1.20.x, and translates it into modern Data Components on 1.21.x.

val legacyNbtString = """
{
  Unbreakable: 1b,
  HideFlags: 1,
  display: {
    Name: '{"text": "Apple of God", "color": "yellow"}',
    Lore: ['{"text": "Grants divine powers..."}']
  }
}
""".trimIndent()

// Parses, cleans, and applies the legacy structure to the item stack
item.applySNBT(legacyNbtString, registries)

βš–οΈ License

This project is licensed under the ZLA License (ZLib Aleksti edition).

You are free to use, modify, and redistribute the source code. You may commercialize compiled binary versions of this mod, but you must keep the source code open-source and compilable for free by anyone. Refer to the LICENSE.md file for full details.

Donate Me ❀️

The NBT to Data API Team

profile avatar
Owner
  • 7
    Projects
  • 13.6K
    Downloads

More from AleksTi

  • ArmsRace project image

    ArmsRace

    • 120
    • Mods

    A fully customizable, standalone Arms Race / Gun Game mini-game for your server. Works perfectly with vanilla items or any weapon mods like TaC:Z! BETA VERSION OF MOD!!!

    • 120
    • July 4, 2026
    • Mods
    • +2
  • ArmsRace project image

    ArmsRace

    • 120
    • Mods

    A fully customizable, standalone Arms Race / Gun Game mini-game for your server. Works perfectly with vanilla items or any weapon mods like TaC:Z! BETA VERSION OF MOD!!!

    • 120
    • July 4, 2026
    • Mods
    • +2