The Last Starship — Recipe Calculator

A tool that generates a dynamic Excel spreadsheet for planning crafting in The Last Starship by Introversion Software. Select any craftable item from a dropdown, enter a desired quantity, and the calculator instantly shows every intermediate component and raw material needed — with batch recipes automatically rounded up to the nearest complete craft run.

Requirements

• Python 3.8+
• pip install pyyaml openpyxl

Generating the Excel file

python build_calculator.py

This reads all .yaml files from the recipes/ folder, computes the full bill of materials for every craftable item, and writes LastStarship_RecipeCalculator.xlsx.

Open the file, select an item from the dropdown in cell B6, enter a quantity in C6, and every required component and raw material is calculated instantly.

Project structure

├── build_calculator.py        ← generates the Excel file from the YAML recipes
├── parse_recipes.py           ← converts recipes.txt (from the game) into YAML
├── config.yaml                ← output filename and alternative raw materials
├── recipes/
│   ├── smelter.yaml           ← manually maintained (hardcoded in game engine)
│   ├── fabricator.yaml        ← parsed from recipes.txt
│   ├── assembler.yaml         ← parsed from recipes.txt
│   ├── refinery.yaml          ← parsed from recipes.txt
│   ├── chemical_lab.yaml      ← parsed from recipes.txt
│   ├── munitions_factory.yaml ← parsed from recipes.txt
│   └── laser_infuser.yaml     ← parsed from recipes.txt
└── LastStarship_RecipeCalculator.xlsx   ← generated output (not versioned)

How recipes work

Each .yaml file in recipes/ contains one or more recipe definitions:

ItemName:
  out: 1                  # how many are produced per craft run (>1 for batches)
  equipment: Assembler    # which machine crafts it (informational only)
  duration: 30.0          # craft time in seconds (informational only)
  ingredients:
    - item: SomeComponent
      qty: 3
    - item: AnotherPart
      qty: 1

Key rules:

• Item names are CamelCase and case-sensitive, matching the game's internal names
• Any ingredient with no recipe of its own is automatically treated as a raw material
• out: 15 means one craft run produces 15 units — the calculator divides ingredient quantities accordingly and rounds up to full batches in the Excel output
• Files starting with _ are ignored by the calculator (used for reference files)

Updating after a game patch

Most recipes live in recipes.txt inside main.dat, which is a standard ZIP archive. When the game updates:

Step 1 — Extract recipes.txt

Rename main.dat to main.zip and open it, or use 7-Zip directly. The file you need is at: data/recipes.txt

Step 2 — Re-parse

python parse_recipes.py path/to/recipes.txt

This overwrites all YAML files in recipes/ except smelter.yaml.

Step 3 — Check smelter.yaml manually

Smelter recipes are hardcoded in the game engine and do not appear in recipes.txt. Open recipes/smelter.yaml and verify the ratios still match the game. Current verified ratios:

ScrapMetal as an alternative source for MetalIngot (3 → 1) is defined in config.yaml under alternatives.

Step 4 — Rebuild

python build_calculator.py

Adding or editing a recipe manually

Open the relevant .yaml file in recipes/ and add or edit an entry, then rerun build_calculator.py. You can also create new .yaml files — any file in the recipes/ folder not starting with _ is picked up automatically.

If the same item name appears in two different files, the script raises an error identifying both files so you can resolve the conflict.

config.yaml reference

recipes_dir: recipes          # folder to load recipe YAML files from

output_file: LastStarship_RecipeCalculator.xlsx  # name of the generated file

alternatives:                 # alternative raw material sources
  - crafted_item: MetalIngot  # the item normally crafted from the primary raw
    alternative: ScrapMetal   # the alternative input
    qty_per_unit: 3           # how many of the alternative per 1 crafted_item

Alternatives appear as extra rows in the Raw Materials section of the spreadsheet, showing how many of the alternative you would need instead.

Notes

• The calculator uses exact rational arithmetic (Fraction) internally to avoid floating-point errors, converting to floats only when writing to Excel
• Batch items (e.g. RefinedMetreon, StableIsotopes) are rounded up to the nearest complete batch in the Crafted Components section of the spreadsheet
• Rows for components not required by the selected item are automatically greyed out rather than hidden, so the layout stays stable as you switch items