Using Operator Mono in Atom

styles.less

/**
 * Using Operator Mono in Atom
 * 
 * 1. Open up Atom Preferences.
 * 2. Click the “Open Config Folder” button.
 * 3. In the new window’s tree view on the left you should see a file called “styles.less”. Open that up.
 * 4. Copy and paste the CSS below into that file. As long as you have Operator Mono SSm installed you should be golden!
 * 5. Tweak away.
 *
 * Theme from the screenshot (http://cdn.typography.com/assets/images/blog/operator_ide2.png):
 * 1. UI Theme: One Dark (comes with Atom, I believe) — https://github.com/atom/one-dark-syntax
 * 2. Syntax Theme: Oceanic Next — https://github.com/voronianski/oceanic-next-theme
 */

atom-workspace,
atom-text-editor {
    font-family: "OperatorMonoSSm-Light";
    font-size: 14px;
    font-weight: normal;
    line-height: 1.7;
}

atom-panel.tool-panel {
    font-size: 0.88em;
}

.editor .comment,
atom-text-editor.editor .syntax--comment {
    font-family: "OperatorMonoSSm-LightItalic";
    font-style: normal;
}

@imyxh, it was actually the font family setting in the font files themselves. Once I changed that setting through FontForge, the problem went away.

@mrclayman — Yes, it depends on how the source fonts want to have their weights declared. With some, you can’t use weight like bold or 700. You have to declare each “style” individually. Hope it worked out in the end!

Indeed, @brandondurham. I use Linux, which usually uses a font configuration system called "fontconfig" that appears to rely on TTF-based weight settings. After tweaking the weight settings in the font files, everything started working beautifully. 👍