UI8px CLI

ui8px is a framework-agnostic CLI for keeping utility-class projects aligned to a strict 8px design grid. It is intended for Tailwind-style workflows where classes remain explicit in source code, while a policy layer prevents drift, raw palette usage, accidental 4px layout spacing, and repeated unreviewed patterns.

Run without installing:

npx ui8px@latest lint ./...

Documentation

For a full onboarding path, read the docs:

• 101: 8px Grid Design
• Why Tailwind
• CLI API Reference
• Policy Files
• Examples And Use Cases
• Testing, CI, And Publishing

Commands

npx ui8px init
npx ui8px init --preset go
npx ui8px lint ./...
npx ui8px lint ./... --ignore .manual .project
npx ui8px lint ./... --learn
npx ui8px validate aria ./...
npx ui8px validate grid --input class-map.json --output class-map.backlog.json
npx ui8px validate patterns ./...
npx ui8px policy review

Legacy class-map validation is still supported:

npx ui8px --design grid --input class-map.json --output class-map.backlog.json

Project Files

ui8px init creates:

.ui8px/
  policy/
    allowed.json
    denied.json
    scopes.json
    groups.json
    patterns.json
  telemetry/
  reports/

If .ui8px is missing, ui8px lint uses bundled defaults. For Go component libraries, use npx ui8px init --preset go to make ui/**, components/**, and utils/**/*.go control scope while examples and views remain strict layout scope.

ui8px reads the current working directory's .gitignore automatically during file scanning, including negation lines (!pattern) that re-include a previously ignored path. Use --ignore to add extra ignored files or folders for a single run:

npx ui8px lint ./... --ignore .manual .project snapshots
npx ui8px validate patterns ./... --ignore fixtures/reference
npx ui8px validate aria ./... --ignore .manual

Place scan paths before --ignore; every non-option value after --ignore is treated as an ignore entry.

8px Spacing Policy

Layout scope is strict 8px:

{
  "spacing": {
    "layout": ["0", "2", "4", "6", "8", "10", "12", "16", "20", "24"],
    "control": ["0", "1", "2", "3", "4", "5", "6", "7", "8", "10", "12"]
  }
}

Examples:

• px-2 = 8px, allowed in layout.
• px-4 = 16px, allowed in layout.
• px-3 = 12px, denied in layout as fine tuning.
• px-3 is allowed in control scope for buttons, fields, badges, tabs, and other compact primitives.

Scopes are file/folder based:

{
  "defaultScope": "layout",
  "scopes": [
    {
      "name": "controls",
      "files": ["src/ui/**", "src/components/**", "ui/**", "components/**"],
      "spacing": "control"
    },
    {
      "name": "layout",
      "files": ["src/views/**", "src/pages/**", "examples/**", "internal/site/views/**"],
      "spacing": "layout"
    }
  ]
}

Linting

npx ui8px lint ./...
npx ui8px lint ./... --ignore .manual .project

Supported source types:

• .templ and .html: static class="..." values. .templ files also go through the Go extractor, so Class: "...", cn(...) / Cn(...), and templ.Attributes{"class": "..."} are recognised.
• .css: @apply ...; utility lists.
• .go: static templ.Attributes{"class": "..."} style values, struct fields Class: "..." (quoted or backtick strings), utils.Cn(...) / utils.cn(...), Cn(...) / cn(...), mixed literal/dynamic cn calls, static return "..." helper strings, and const / var string declarations (including grouped const ( ... ) / var ( ... ) blocks) whose values look like utility lists.

Go examples:

return utils.Cn(base, "px-3", props.Class)
return cn("inline-flex items-center", props.Class)

return CardProps{Class: "h-8 px-3 text-sm"}

const ButtonBase = "inline-flex items-center"
var ButtonPad = `px-3 py-1`
const (
  ButtonRow = "flex items-center gap-2"
)

return "h-8 px-3 text-sm"

The extractor reads only static string literals. It does not execute Go code and ignores dynamic arguments. Each string literal argument to cn / Cn is linted as its own class list, so mutually exclusive conditional branches do not report a false UI8PX004 conflict.

Checked files is the number of supported source files scanned, including files that contained no class lists.

Tailwind v4 inset-ring, inset-ring-*, and inset-shadow-* are ring/shadow utilities, not positional inset-* spacing, so they are not checked against the spacing scale and are not grouped with inset-0. Positional inset-x-* and inset-y-* are treated as their own spacing prefixes.

By default, lint scanning skips built-in transient folders (.git, .ui8px, node_modules, dist, coverage/cache folders) and entries from the local .gitignore.

Example diagnostic:

src/views/landing.templ:24:16 UI8PX001 disallowed utility class "px-3"
Scope: layout
Reason: px-3 is not allowed in layout scope.
Suggestion: use px-2 or px-4

Rules:

• UI8PX001: disallowed spacing token for current scope.
• UI8PX002: utility class not in allowed policy.
• UI8PX003: utility class is explicitly denied.
• UI8PX004: conflicting utilities inside the same class list.
• UI8PX005: unknown ui-* semantic class.

Learn Mode

npx ui8px lint ./... --learn

Learn mode writes:

.ui8px/telemetry/observed.jsonl
.ui8px/telemetry/proposals.json

Plain lint does not mutate files. --learn records unknown, denied, and disallowed classes so a developer or LLM-assisted workflow can review recurring issues later.

Pattern Discovery

npx ui8px validate patterns ./...

This command finds repeated class-list compositions. It normalizes class order, removes internal duplicates, resolves simple conflict groups, and writes:

.ui8px/reports/patterns.json

Example:

Repeated pattern found 14 times:
  flex items-center justify-between gap-4 px-6 py-4
Suggested semantic class:
  ui-section-header

ui8px does not automatically generate @apply CSS. It reports candidates so semantic ui-* patterns can be reviewed intentionally.

ARIA Bundle Validation

npx ui8px validate aria ./...

This command scans source files for static data-ui8kit="..." hooks and common UI8Kit component calls such as @ui8layout.Shell(...), @ui.Accordion(...), and @ui.Tabs(...). It checks that the matching @ui8kit/aria pattern is included in the site bundle. It reads the generated web/static/js/manifest.json when present, otherwise it falls back to package.json ui8kit.aria.

Examples:

• data-ui8kit="dialog" requires the dialog pattern.
• data-ui8kit="sheet" and data-ui8kit="alertdialog" also require dialog.
• data-ui8kit="tabs" requires tabs.
• @ui8layout.Shell(...) requires dialog because the shell owns a mobile sheet.

Use --package <path> or --manifest <path> when the files live outside the current working directory.

Grid Map Validation

The existing map validator remains available:

npx ui8px validate grid --input class-map.json --output class-map.backlog.json

It checks CSS declaration values in a class map and reports values that do not resolve to the 8/4px grid.

Exit Codes

• 0 — no blocking violations.
• 1 — lint, grid, or pattern violations found.
• 2 — invalid usage or runtime error.

Publishing

Before publishing:

npm run preflight
npm publish --access public --provenance