The Assay design system.
v1 · 2026
An assay is the definitive test of a metal's purity, and a hallmark is the struck record of that test. The system borrows its whole language from that ritual: paper and ink for the certificate, one disciplined gold for the mark, monospace for the evidence.
Identity
The cartouche.
On a hallmark, the fineness of gold is stamped inside an oblong with cut corners. The Assay mark is that surround, struck with an A whose flat apex and flat-topped counter echo the chamfers. It is the mark of the authority that does the testing.
Lockup
Instrument Sans · semibold · tracking tight · mark height matches cap height
Scale
Outline above 20px; the punch variant carries favicons and tight sizes
Color
Paper, ink, and one gold.
Warm neutrals carry everything. Gold is struck in small doses where it means verification, evidence, or action. On light surfaces, gold-600 and deeper are the only text golds; gold-500 is reserved for graphics.
Warm neutrals
paper
#f9f8f5
Page canvas
surface
#fefdfc
Raised cards
linen
#efece8
Quiet fills
mist
#e0ded8
Hairlines, borders
stone
#6d6861
Muted text (AA on paper)
ink-soft
#3c3a36
Secondary text
ink
#1b1915
Primary text, buttons
black
#0c0b08
Dark-mode canvas
Assay gold
gold-050
#fcf6ec
Wash, hover tint
gold-200
#f0dcb1
Tints, selection
gold-300
#edc980
Large accents on dark
gold-400
#e7b551
Accent text on dark
gold-500
#d19936
Identity core. Graphic-only on light
gold-600
#94631a
Gold as text on light
gold-700
#794f1a
Deep gold, hover state
On light
Ink on paper for prose. Gold-600 for links and accents. Stone for supporting text.
On dark
Warm white on near-black. Gold-400 carries the accent. Fog for supporting text.
Typography
A sans for the argument, a mono for the record.
Instrument Sans carries display and prose. Commit Mono, a deliberately neutral programming face, carries labels, dates, and figures: anything that reads as evidence rather than argument. Both are open licensed and self-hosted.
Display
60px / semibold / -0.02em
The proof is in the deploy
Title
36px / semibold / -0.01em
The proof is in the deploy
Heading
24px / semibold
The proof is in the deploy
Body
17px / regular / 1.75
The proof is in the deploy
Small
14px / regular / 1.6
The proof is in the deploy
Label
11px / mono / caps / 0.14em
The proof is in the deploy
Commit Mono figures
0123456789
record 2026-07-02T09:14:07Z · signature verified · ledger append accepted
In use
The tokens at work.
Shared shadcn/ui components from the workspace library, rendered with nothing but the brand tokens. No component ships custom colors.
Buttons
Badges
Form
Principles
Six rules the system keeps.
Struck, not rendered
Flat color, crisp edges, small radii. The brand behaves like a punch mark in metal: no gradients, no bevels, no metallic sheen.
Hairlines, not shadows
Structure comes from one-pixel rules and spacing. Elevation is reserved for surfaces that truly float.
Gold means something
The accent marks evidence, verification, and action. It never decorates. Most of any page is paper and ink.
Mono is for the record
Commit Mono carries labels, figures, dates, and anything that reads as evidence. Prose stays in the sans.
Contrast is computed
Every text-on-surface pair is verified against WCAG AA in both modes before it ships. Nothing is eyeballed.
Motion earns its place
A calm reveal on entry, a considered hover, nothing perpetual. Reduced-motion preferences collapse it all to static.