# Your first datapack

> A step-by-step datapack: add a Burner Press recipe, remove one of HBM's, and check that it loaded.

This walkthrough builds a working datapack in five steps: it adds a Burner Press recipe that presses a gold block
into a diamond (an obviously new result, so it is easy to spot) and removes one of HBM's press recipes. The same pack
works on all six targets once the folder names match your Minecraft version.

<Steps>

1. **Make the pack folder.** Open your world's `datapacks` folder (`saves/<world>/datapacks`) and create a folder
   named `my_hbm_pack`. Everything below goes inside it. Use your own namespace (`mypack` here) for your files, never
   `hbm`.

2. **Write `pack.mcmeta`.** The format number depends on the Minecraft version:

   <Tabs syncKey="mc">
   <TabItem label="26.1">
   ```json title="pack.mcmeta"
   {
     "pack": {
       "description": "My HBM tweaks",
       "min_format": 101,
       "max_format": 101
     }
   }
   ```
   </TabItem>
   <TabItem label="1.21.1">
   ```json title="pack.mcmeta"
   {
     "pack": {
       "description": "My HBM tweaks",
       "pack_format": 48
     }
   }
   ```
   </TabItem>
   <TabItem label="1.20.1">
   ```json title="pack.mcmeta"
   {
     "pack": {
       "description": "My HBM tweaks",
       "pack_format": 15
     }
   }
   ```
   </TabItem>
   </Tabs>

3. **Add the recipe.** Machine recipes live in a subfolder named after the machine's table, here `press`:

   <Tabs syncKey="mc">
   <TabItem label="26.1 and 1.21.1">
   <FileTree>
   - my_hbm_pack/
     - pack.mcmeta
     - data/
       - mypack/
         - recipe/
           - press/
             - diamond_from_gold.json
   </FileTree>
   </TabItem>
   <TabItem label="1.20.1">
   <FileTree>
   - my_hbm_pack/
     - pack.mcmeta
     - data/
       - mypack/
         - recipes/
           - press/
             - diamond_from_gold.json
   </FileTree>
   </TabItem>
   </Tabs>

   ```json title="data/mypack/recipe/press/diamond_from_gold.json"
   {
     "type": "hbm:press",
     "stamp": "flat",
     "input": { "ingredient": "minecraft:gold_block" },
     "output": "minecraft:diamond"
   }
   ```

   `stamp` is the stamp the press needs: `flat`, `plate`, `wire`, `circuit`, `c357`, `c44`, `c9`, `c50` or
   `printing1` to `printing8`. `input` takes an item or a `#tag`, with an optional `count`; `output` is an item id or
   `{"id", "count"}`. The machine recipe JSON is the same on every version, including 1.20.1. The `type` field picks
   the table, so the subfolder name only keeps the recipe id readable (`mypack:press/diamond_from_gold`). Every field
   is on the [press page](https://warfactory-official.github.io/Continuum-Wiki/datapacks/recipes/press-and-grinding/#press).

4. **Remove an HBM recipe.** Removals are a list of recipe ids in a `recipe_removals` folder of your own namespace.
   A machine recipe's id is `hbm:<table>/<file name>`:

   ```json title="data/mypack/recipe_removals/press.json"
   {
     "recipes": ["hbm:press/ball_resin"]
   }
   ```

   This removes the press recipe that turns jungle logs into latex. Do not try to override HBM's file by writing your
   own `data/hbm/recipe/press/ball_resin.json`: which pack wins is not reliable on every loader.

5. **Load it.** Run `/reload` in the world (or restart it). Machine tables are re-read and synced to every client on
   reload. Run `/datapack list` and check that `file/my_hbm_pack` is enabled. Then put a flat stamp, a gold block and
   some fuel in a Burner Press: it presses a diamond once it has heated up. A jungle log with a flat stamp no longer
   gives latex.

</Steps>

## If nothing happens

- `/datapack list` does not show the pack: `pack.mcmeta` is missing, misnamed or has the wrong keys for your version,
  or the files are one folder too deep (the pack folder must contain `pack.mcmeta` and `data/` directly).
- The pack is listed but the recipe is missing: check the folder name (`recipe` or `recipes`) for your version, and
  look in the game log for a recipe parsing error naming your file.
- A JSON syntax error (a missing comma or quote) makes the game skip that one file. A JSON validator finds it fastest.

## Where to find HBM's own recipes

HBM's recipes are generated at build time, so they are not in the source repository as JSON. To read them, open the
NTM - Continuum jar with any zip tool and look under `data/hbm/recipe/<table>/` (`recipes/` on 1.20.1). They are the best
examples for every table.

## Next steps

- [Machine recipes overview](https://warfactory-official.github.io/Continuum-Wiki/datapacks/recipes/overview/) explains ids, ordering and every table.
- [Common fields](https://warfactory-official.github.io/Continuum-Wiki/datapacks/recipes/common-fields/) documents the schema most machines share.
- [Data maps](https://warfactory-official.github.io/Continuum-Wiki/datapacks/data-maps/overview/) change hazards, fuels and other per-item values.
- [What a datapack can change](https://warfactory-official.github.io/Continuum-Wiki/datapacks/overview/) lists every other folder.
- [Key concepts](https://warfactory-official.github.io/Continuum-Wiki/getting-started/concepts/) explains ids, units and the version differences.