parts.yml reference¶

Every part in the Snakie Parts Library is a folder with one parts.yml file inside it. That file describes the part — its name, its pins, and how to draw it. This page lists every field you can put in it.

A part is a piece of hardware, like a sensor or a motor driver. YAML is a simple text format that uses key: value lines.

You rarely type this by hand

The visual Part Editor writes parts.yml for you. This page is here for when you want to read, tweak, or understand a part file. To make a part step by step, see Make a part. For the bigger picture, see The Parts Library.

Only id, name, and at least one headers entry are required. Everything else is optional.

📸 Screenshot

Show: a parts.yml file open in the editor next to the part it draws in the Board View.

Catalogue fields (the header)¶

These describe the part in the library and let people search for it.

Field	What it is
`id`	A unique name inside its library. It is also the part's folder name (e.g. `vl53l0x`). Required.
`name`	The friendly display name (e.g. `VL53L0X ToF`). Required.
`description`	One short line about the part.
`manufacturer`	Who makes it (e.g. `Pimoroni`, `Raspberry Pi`).
`partNumber`	The maker's part number (e.g. `SC0918`).
`family`	The category (e.g. `Sensor`, `Microcontroller`, `Motor Driver`).
`tags`	A list of words to help searching (e.g. `[i2c, distance]`).
`package`	How it mounts: `THT` (through-hole) or `SMD` (surface-mount).
`pinSpacing`	The gap between pins in millimetres. The common header value is `2.54`.
`voltage`	Working voltage as free text (e.g. `3.3V`).
`properties`	Your own extra spec rows as `key: value` pairs.
`version`	The part's own version number, like `1.0.0`. Used to spot updates.

Shape and size fields¶

These control how the board is drawn.

Field	What it is
`dimensions`	The real size in millimetres, written `{ width: 25, height: 11 }`.
`aspect`	Width divided by height — sets the drawn proportions.
`pcbColor`	The board colour (any CSS colour, e.g. `'#101820'`).
`polygon`	An outline for non-rectangular boards: a list of `{ x, y }` points from `0` to `1`. Leave it out for a plain rounded rectangle.
`shape`	The outline kind: `rect` (default) or `polygon`.

Pins¶

Pins are grouped into headers. Each header is a row of pins along one edge.

headers:
  - edge: bottom          # left | right | top | bottom
    pins:
      - { name: VIN, type: pwr, number: 1 }
      - { name: SDA, type: io,  number: 3, gpio: 4, capabilities: [i2c, digital] }

Each pin can have these fields:

Pin field	What it is
`name`	The pin's signal name (e.g. `GP0`, `SDA`, `VBUS`). Required.
`label`	Different text to print, if it differs from `name`.
`type`	The pin's job: `pwr` (power), `gnd` (ground), `io` (a usable GPIO), or `other`.
`number`	The physical pin number printed on the board, if any.
`gpio`	The GPIO number this pin uses. Snakie matches it to `Pin(n)` in your code. `io` pins only.
`capabilities`	What an `io` pin can do (a list): `digital`, `pwm`, `adc`, `i2c`, `spi`, `uart`.
`shape`	How the pad looks: `round`, `square`, `castellated`, or `header`.
`x` / `y`	Exact spot on the board, from `0` to `1`. Set by the editor's free placement.

io pins carry the extras

gpio and capabilities only matter on io pins. Snakie ignores them on power and ground pins.

Holes, shapes, and labels¶

Field	What it is
`mountingHoles`	Screw holes. Each is `{ x, y, diameter }` — position `0`–`1` and diameter in mm.
`shapes`	Drawn components: a list of `rect`, `circle`, or `polygon` shapes with `fill`, `stroke`, and a position.
`labels`	Free text placed on the board: `{ text, x, y }`, with optional `fontSize`.

Assets and drivers¶

Field	What it is
`image`	The filename of a board photo in the same folder (e.g. `image.png`).
`help`	The filename of a small Markdown help file (e.g. `help.md`) shown when the part is used.
`drivers`	MicroPython files the part needs on the board. Each has `source`, `target`, and an optional `label`.
`mesh`	A 3-D model file (STL) in the folder for the Robot View, e.g. `model.stl`.
`meshUnits`	The mesh's units so it loads at the right size: `mm` or `m`.

A full annotated example¶

id: vl53l0x                       # unique; also the folder name
name: VL53L0X ToF                 # display name
description: Time-of-flight distance sensor
manufacturer: STMicroelectronics
family: Sensor
partNumber: VL53L0X
tags: [i2c, distance, tof]
package: SMD                      # THT | SMD
pinSpacing: 2.54                  # header gap, millimetres
voltage: 2.8–5V
version: 1.0.0                    # this part's version

# --- shape & size ---
pcbColor: '#101820'
aspect: 1.3
dimensions: { width: 25, height: 11 }

# --- pins ---
headers:
  - edge: bottom                  # left | right | top | bottom
    pins:
      - { name: VIN, type: pwr, number: 1 }
      - { name: GND, type: gnd, number: 2 }
      - { name: SCL, type: io, number: 3, gpio: 5, capabilities: [i2c, digital], shape: castellated }
      - { name: SDA, type: io, number: 4, gpio: 4, capabilities: [i2c, digital], shape: castellated }

# --- holes, shapes, labels ---
mountingHoles:
  - { x: 0.1, y: 0.5, diameter: 2 }
labels:
  - { text: XSHUT, x: 0.8, y: 0.5 }

# --- assets & drivers ---
image: image.png                  # a photo in this folder
help: help.md                     # optional help notes
drivers:
  - { source: github:org/repo/vl53l0x.py, target: lib, label: VL53L0X driver }

One typo won't break everything

If a parts.yml is malformed, Snakie skips just that part and still loads the rest of the library. Check spelling and indentation if a part goes missing.