A gift from Slatis engineers to other engineers who work while everyone sleeps.
Nyx was the goddess of night, and in every telling, night is not the absence of something. It is its own thing, first-born, with its own weather. The room gets quiet, the meetings stop, and what is left is you and the problem(s).
Around 1 in 12 men & 1 in 200 women have some form of colour vision deficiency, and syntax highlighting asks them to pull meaning out of hue for eight hours a day. Most themes hand them two roles painted the same colour and ship it.
Slatis Nyx generates six variants from one source palette. Three target a specific deficiency, one drops colour out of the interface completely, and the build refuses to finish when two syntax roles could read as the same colour.
- Functions render purple
#c9a3f0, so the interface accent and the code never share a hue. - Borders: Two bands with one rule:
#2c2e2dfor surfaces that sit inside the layout,#383a39for surfaces that float over content. - Semantic highlighting, on. 39 rules keyed off the language server, so
readonlylocals,defaultLibrarysymbols and declarations each read differently from a plain identifier. - Punctuation recedes to
#8e8f8fand lets keywords own the accent. - Every surface is covered. Terminal ANSI, diff, merge, git decorations, bracket pairs, inlay hints, sticky scroll, the command centre, the source control graph, symbol icons, and the chat view.
| Theme | Use it when |
|---|---|
| Slatis Nyx | The default. Full colour, GitHub Dark Classic syntax. |
| Slatis Nyx (Dimmed) | Long sessions. Saturation and brightness drop together, so the whole surface sits about five contrast points lower. |
| Slatis Nyx (Mono) | Greyscale interface. Colour survives in syntax, terminal, and 41 risk signals. |
| Slatis Nyx (Deuteranopia) | Red-green colour vision deficiency, covering deuteranopia and protanopia. |
| Slatis Nyx (Tritanopia) | Blue-yellow colour vision deficiency. |
| Slatis Nyx (High Contrast) | Low vision. Ships as uiTheme: hc-black. |
Syntax highlighting asks them to pull meaning out of hue for eight hours a day, and most themes hand them two roles painted the same colour.
Three variants target a specific deficiency, and a fourth removes the question entirely.
| Variant | Covers | What moves |
|---|---|---|
| Deuteranopia | deuteranopia, protanopia | Green becomes blue and red becomes amber. The red-green axis turns into amber-blue. |
| Tritanopia | tritanopia | Green becomes blue and orange becomes red. The axis turns into red-blue. |
| Mono | achromatopsia, and any deficiency at once | The interface goes greyscale. Syntax, terminal and 41 risk-signal keys keep their colour. |
| High Contrast | low vision | Every hue brightens, borders move up a band, and VS Code draws its own contrast borders on every widget. |
Deuteranopia and Tritanopia keep the interface exactly as the default theme paints it. What moves is the syntax palette, the git and diff signals, the 16 terminal ANSI colours and the source control graph lanes, which is everywhere colour carries meaning rather than identity.
Every variant is generated from one source theme by scripts/build-variant.js,
and the build refuses to finish when two of the ten syntax roles could read as
the same colour.
A pair passes when at least one of three channels carries the difference:
- a luminance gap of 0.03
- a hue gap of 70 degrees
- one of them sitting near neutral, where chroma does the work
Hue remapping on its own leaves pairs that match in both hue and value.
Measuring all 45 pairs in each variant surfaced entity and tag sitting
0.001 apart in luminance and 61 degrees apart in hue, which lands as a single
colour for a deuteranope. The palettes moved until the check passed.
Read-only symbols render bold in every accessibility variant, so a constant stays identifiable with hue stripped out completely. Deprecated symbols are struck through in all six.
Mono takes the idea furthest. The git gutter separates added, modified and deleted by lightness, and 41 keys covering errors, warnings, merge conflicts, offline state and breakpoints hold their colour, so a failure still announces itself in a greyscale interface.
These live in settings, beyond the reach of any colour file:
| Role | Hex | On #0b0b0b |
|---|---|---|
| Accent (UI) | #4589ff |
5.9:1 |
| Link / bright | #78a9ff |
8.4:1 |
| Fill only | #0f62fe |
3.9:1 |
| Error / badge | #fa4d56 |
|
| Added / success | #42be65 |
|
| Warning | #f1c21b |
Badges split by intent. Counters that report a change, like git and extensions,
come through activityBarBadge in blue. Anything asking for attention comes
through activityErrorBadge in red or activityWarningBadge in yellow.
The command centre, sticky scroll and the active activity-bar item use alpha compositing, so layers read as stacked glass. Alpha composites against the workbench surface underneath. VS Code has no window-level transparency, so the desktop stays hidden.
Search Slatis Nyx in the Extensions view and install it. Then press
Cmd+K Cmd+T (Ctrl+K Ctrl+T on Windows and Linux) and pick a variant.
From a terminal:
code --install-extension utreras.slatis-nyx # Visual Studio Code
cursor --install-extension utreras.slatis-nyx # Cursor
windsurf --install-extension utreras.slatis-nyx # Windsurf
codium --install-extension utreras.slatis-nyx # VSCodiumPublished to both registries, so every VS Code-compatible editor can reach it:
| Editor | Pulls from |
|---|---|
| Visual Studio Code | Visual Studio Marketplace |
| Cursor | Open VSX |
| Windsurf | Open VSX |
| VSCodium, Gitpod, code-server, Eclipse Theia | Open VSX |
Editors that ship their own registry mirror Open VSX, so one publish there
covers all of them. Zed has its own port with all six variants, and
terminal/ carries the palette to iTerm2, Ghostty, Alacritty,
Kitty, Warp and Windows Terminal. Grabbing the .vsix from either page and running
Extensions: Install from VSIX works everywhere as a fallback.
MIT
Built by Slatis Team, for the ones still typing (or chatting) at 3am.
www.slatis.com
{ // Force a minimum contrast ratio in the terminal, overriding program colours "terminal.integrated.minimumContrastRatio": 4.5, // Heavier glyphs help low vision more than brighter ones "editor.fontWeight": "500", "workbench.fontAliasing": "antialiased", // A wider, steady caret is easier to track "editor.cursorWidth": 3, "editor.cursorBlinking": "solid", // Audio cues that run independently of anything visual "accessibility.signals.lineHasError": { "sound": "on" }, "accessibility.signals.lineHasWarning": { "sound": "on" }, // Structure that survives without colour "editor.guides.bracketPairs": "active", "editor.renderWhitespace": "boundary" }