Ioskeley Mono

An open programming typeface built on Iosevka.
Compact, geometric, and tuned for editors and terminals.

Live Showcase  ·  Download  ·  Install  ·  Story

Ioskeley Mono is a free, open-source programming typeface: ten weights, two widths, upright and italic, in three families for editors, terminals, and apps that cannot turn ligatures off. It is built for long days of reading code, with technical character and no visual noise.

_{Explorer, editors, terminal and status bar: one typeface at three sizes. The Live Showcase follows a full working day in Ioskeley (editor, terminal, review, logs, queries and docs) and has a live specimen you can type into.}

Why I Built Ioskeley Mono

Berkeley Mono was the first typeface that made me think seriously about how much character could live in a compact programming font. I admired its geometry and technical presence, but it was a commercial font I could not justify buying at the time. I wanted to explore that kind of carefully made type, and make the result freely available.

Finding Iosevka gave me a way to do that. I generated and tested more than a hundred builds, adjusting forms, spacing and proportions, then trying each iteration in real editors and terminals. That process began with a reference in mind; the accumulated decisions gradually became Ioskeley.

Ioskeley is now its own open typeface, not a clone or a specification match. Berkeley Mono remains part of its history, while Iosevka is the foundation that made the experiment possible.

Choose Your Ioskeley

Every family has the same 40 styles: ten weights from Thin to Black, Normal and SemiCondensed widths, upright and italic.

Two widths, both in every desktop and Nerd Font archive:

• Normal (600 units): the standard balance of spacing and readability.
• SemiCondensed (540 units, 90% of Normal): more characters on a line.

NL keeps ordinary character shaping; it only drops the programming ligatures.

Nerd Font or Nerd Font Mono?

Starting with 2.2.0, every Nerd Font archive contains both patched variants:

• Nerd Font (NF): ordinary Nerd Fonts geometry with larger icons. A good starting point for most setups that want icons; some icons may extend beyond one cell.
• Nerd Font Mono (NFM): strict one-cell advances for applications or font pickers that require true monospace behavior.

Neither is universally better. Choose the geometry your application expects.

_{Box drawing meets at a line height of exactly 1.25, where the font's own metrics put it. Shown in the Standard web build; Term tunes arrows and box drawing to the terminal cell.}

Downloads

These links always serve the latest published release.

@font-face {
  font-family: "Ioskeley Mono";
  src: url("./IoskeleyMono-Regular.woff2") format("woff2");
  font-style: normal;
  font-weight: 400;
  font-display: swap;
}

Installation

Package Managers

These community packages may update on a different schedule from GitHub Releases.

Thanks to @zhimoe, @dave-atx, @ForsakenHarmony, and @frovere for helping bring Ioskeley to Homebrew.

Manual Installation

1. Download and unzip the family archive you want.
2. Choose Normal or SemiCondensed. For standard-density Windows/Linux displays, install from Hinted; for macOS or HiDPI displays, choose Unhinted. Nerd Font archives do not split into hinted/unhinted folders.
3. Install the .ttf files for your chosen width and rendering set:
   • Windows: right-click and choose Install (or Install for all users).
   • macOS: open the fonts in Font Book and choose Install.
   • Linux: copy them to ~/.local/share/fonts/IoskeleyMono/, then run fc-cache -fv.

Restart open applications so they refresh their font lists.

Editors and Terminals

Use the family name matching the package you installed: Ioskeley Mono, Ioskeley Mono Term, or Ioskeley Mono NL. Patched families add a Nerd Font or Nerd Font Mono suffix; select the full installed name in your font picker.

VS Code / Cursor

{
  "editor.fontFamily": "'Ioskeley Mono', monospace",
  "editor.fontLigatures": true,
  "editor.fontWeight": "400",
  "editor.fontSize": 14.5,
  "editor.lineHeight": 1.55
}

For an app that cannot disable programming ligatures, install NL and use Ioskeley Mono NL. For patched icons, select the NF or NFM family you installed.

Ghostty

font-family = Ioskeley Mono Term
font-size = 14

Kitty

font_family      Ioskeley Mono Term
bold_font        auto
italic_font      auto
bold_italic_font auto
font_size        14.0

Type Details

Ioskeley is built from Iosevka, but it is not a stock Iosevka preset. Its build plan defines its glyph forms, widths, slopes, spacing, and vertical metrics. The forms are chosen to be read, not noticed: a single-storey g, dotted zero, open 6 and 9, and programming punctuation that stays distinct at small sizes.

Where an application exposes OpenType features:

For example, VS Code can enable the slashed zero alongside its ligatures:

"editor.fontLigatures": "'calt', 'zero'"

The project's visual language follows the typeface: monochrome and typography-first, with one sparing accent. See the visual identity reference.

Origins

Berkeley Mono / TX-02 inspired the first experiment, but it is a reference in Ioskeley's history, not its specification. Iosevka made the exploration possible; repeated tuning shaped a distinct set of proportions and forms.

Historical character, overlay, and code studies

These studies document the project's origins. They are not claims of visual equivalence and do not define the current design direction. TX-02 is a commercial typeface; its files are not included or distributed here.

01 · Character forms

02 · Overlay study

03 · Code texture

Build from Source

The build, validation, and release guide covers prerequisites, reproducible builds, validation, packaging, and the publishing boundary. The private-build-plans.toml file is the source for glyph and metric configuration; tagged builds use the pinned Iosevka source.

Contributing

Bug reports, glyph refinement proposals, documentation fixes, and build-plan improvements are welcome.

• Review the build plan before proposing a glyph or metric adjustment.
• Use GitHub Issues for reproducible problems and design suggestions.
• Send a pull request when you have a tested change.

Support

Ioskeley is free, and every style is in the open release; there is no paid edition and nothing held back.

If it has become part of how you work, you can help keep it maintained through GitHub Sponsors. Sponsorship goes into the quiet work behind each release: testing builds across editors, terminals and platforms, keeping the packages, showcase and documentation in order, and continuing to refine the forms.

A star, a careful bug report, or a screenshot of your setup helps too.

License and Acknowledgments

Ioskeley Mono is released under the SIL Open Font License 1.1, which permits personal and commercial use subject to its terms. Ioskeley is built with Iosevka, created by Belleve Invis and its contributors. The icon variants use the Nerd Fonts project; upstream projects and assets remain subject to their own licenses.

Berkeley Mono is a commercial typeface by Neil Panchal at Berkeley Graphics. Ioskeley is independent and is not affiliated with or endorsed by Berkeley Graphics. If the original design interests you, consider supporting its creator through Berkeley Graphics.

Author: Ahmed Hatem [email protected]