### Clone and Install Fontmake from Source

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Clone the fontmake repository and install it using pip. This is the standard method for developers to get the latest version.

```bash
git clone https://github.com/googlefonts/fontmake
cd fontmake
pip install .
```

--------------------------------

### Install fontmake

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Install fontmake using pip. Ensure you have Python 3.10 or later.

```bash
pip3 install fontmake
```

--------------------------------

### Install Fontmake from Source in Editable Mode

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Install fontmake from a local source checkout using the --editable option. This allows for quick testing of source code changes without re-installation.

```bash
pip install -e .
```

--------------------------------

### Specify Output File Formats

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Use the '-o' flag to specify one or more output file formats. For example, '-o otf ttf' creates both OTF and TTF binaries.

```bash
fontmake -o otf ttf
```

--------------------------------

### Create and Push Git Tag for New Version

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Steps to create an annotated Git tag for a new version and push it to the origin. This is part of the release process for a new version.

```bash
git tag -a v3.1.1
git push origin v3.1.1
```

--------------------------------

### Specify Input Source Files

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Use flags to specify the input source file format. Mutually exclusive options include -g for Glyphs, -u for UFO(Z), and -m for Designspace.

```bash
fontmake -g filename.glyphs
```

```bash
fontmake -u filename.ufo
```

```bash
fontmake -m filename.designspace
```

--------------------------------

### Set Output Directory

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Use the '--output-dir' option to specify a custom directory for all output files, overriding the default per-format directories.

```bash
fontmake --output-dir <some_directory>
```

--------------------------------

### Set Specific Output Path

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Use '--output-path' to write a single binary output file to a specific filename. This is only valid when generating a single binary.

```bash
fontmake --output-path <filename>
```

--------------------------------

### Upgrade fontmake

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Upgrade fontmake and its dependencies to the latest available release using pip.

```bash
pip3 install -U fontmake
```

--------------------------------

### Interpolate Static Instances

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Use the '-i' flag to interpolate and generate static instances from defined instances in your Glyphs file. These are placed in instance directories.

```bash
fontmake -i
```

--------------------------------

### Define a filter in UFO lib.plist

Source: https://github.com/googlefonts/fontmake/blob/main/USAGE.md

Add a filter entry to the UFO lib.plist to execute a specific filter class during the preprocessing step.

```xml
    <key>com.github.googlei18n.ufo2ft.filters</key>
    <array>
      <dict>
        <key>name</key>
        <string>eraseOpenCorners</string>
        <key>namespace</key>
        <string>glyphsLib.filters</string>
        <key>pre</key>
        <true/>
      </dict>
    </array>
```

--------------------------------

### Use Positional Arguments with Options

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

When options that take arguments precede positional arguments, use the '--' separator to ensure all following arguments are treated as non-options.

```bash
fontmake -i -- MyFont.designspace
```

--------------------------------

### Flatten Components

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Use the '-f' flag to flatten components, decomposing nested components to a single level. This is recommended for compatibility with certain rendering environments.

```bash
fontmake -f
```

--------------------------------

### Configure KernFeatureWriter Mode

Source: https://github.com/googlefonts/fontmake/blob/main/USAGE.md

Use this lib key to set the 'mode' option for the KernFeatureWriter to 'append'. This adds generated kerning rules to the end of an existing 'kern' feature.

```xml
<key>com.github.googlei18n.ufo2ft.featureWriters</key>
    <array>
        <dict>
            <key>class</key>
            <string>KernFeatureWriter</string>
            <key>options</key>
            <dict>
                <key>mode</key>
                <string>append</string>
            </dict>
        </dict>
    </array>
```

--------------------------------

### Compile Variable Font from Glyphs

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

Compile a variable font from a Glyphs source file. The '-o variable' flag specifies the output format.

```bash
fontmake MyFont.glyphs -o variable
```

--------------------------------

### Configure Transformations Filter in UFO Lib

Source: https://github.com/googlefonts/fontmake/blob/main/USAGE.md

Use this XML structure in the UFO lib to apply scaling and translation transformations to specific glyphs.

```xml
    <key>com.github.googlei18n.ufo2ft.filters</key>
    <array>
      <dict>
        <key>name</key>
        <string>transformations</string>
        <key>kwargs</key>
        <dict>
            <key>OffsetX</key>
            <integer>0</integer>
            <key>OffsetY</key>
            <integer>150</integer>
            <key>ScaleX</key>
            <integer>75</integer>
            <key>ScaleY</key>
            <integer>75</integer>
        </dict>
        <key>include</key>
        <array>
            <string>A</string>
            <string>B</string>
        </array>
      </dict>
    </array>
```

--------------------------------

### Infer Input Format from Positional Arguments

Source: https://github.com/googlefonts/fontmake/blob/main/README.md

fontmake can infer the input source format from the file extension when provided as positional arguments without a flag.

```bash
fontmake MyFont.designspace
```

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