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🧱 Structure of a Brick

🚀 Overview

If we take a closer look at the example brick we just generated, it should look like:

├── __brick__
└── brick.yaml

The CHANGELOG, LICENSE, and README are all standard files found across many projects so we won't focus on them. The two important entities are the __brick__ directory and the brick.yaml file.


The brick.yaml file is a manifest which contains metadata for the current brick. The newly generated brick.yaml should look something like:

name: example
description: A new brick created with the Mason CLI.

# The following defines the brick repository url.
# Uncomment and update the following line before publishing the brick.
# repository:

# The following defines the version and build number for your brick.
# A version number is three numbers separated by dots, like 1.2.34
# followed by an optional build number (separated by a +).
version: 0.1.0+1

# The following defines the environment for the current brick.
# It includes the version of mason that the brick requires.
mason: '>=0.1.0-dev <0.1.0'

# Variables specify dynamic values that your brick depends on.
# Zero or more variables can be specified for a given brick.
# Each variable has:
# * a type (string, number, boolean, enum, or array)
# * an optional short description
# * an optional default value
# * an optional list of default values (array only)
# * an optional prompt phrase used when asking for the variable
# * a list of values (enums only)
type: string
description: Your name
default: Dash
prompt: What is your name?

Variable Types

Variables defined in your brick.yaml can be one of the following types:

stringA primitive string"Dash"
numberA primitive number42
booleanA primitive booleantrue/false
enumAn enumeration (single choice)["red", "green", "blue"] -> "red"
arrayAn array of strings (multiple choices)["red", "green", "blue"] -> ["red", "blue"]
listA dynamic list of strings (open ended)["c++", "dart", "python"]


The __brick__ directory contains the template for your brick. Any files, directories within the __brick__ will be generated when the brick is used via mason make.

In the example brick, our __brick__ directory contains a single file called with the following content:

# Hello {{name}}!

Templates currently support mustache but support for additional templating specifications is on the roadmap.


Refer to the mustache specification for more information about mustache and its capabilities.