File format spec

§14

Defaults

Status

Stable (format version 1.0.0, frozen 2026-10). Backward compatible within 1.x (§16.4). Supersedes the draft v0.1, kept as a historical record; 0.1 files open through the 0.1 → 1.0 migration (§16.2).

Schema

https://getkimo.design/schema/kimo-1.0.json (JSON Schema draft 2020-12), generated into packages/core-schema/schema/kimo-1.0.schema.json. The 0.1 schema stays published at …/kimo-0.1.json (schema/kimo-0.1.schema.json, frozen).

Reference

@kimo/core-schema (packages/core-schema). Where this document and the implementation disagree, that is a bug in one of them; file an issue.

Plan of record

docs/teardown.md §10. Every place where this spec resolves an ambiguity in, or deviates from, that section is listed in §20.

License

MIT

A property equal to its default means exactly the same as the absent property. Canonical writers omit it (§15). The table is data in @kimo/core-schema (DEFAULTS); the JSON Schema default keywords and the writer's omit logic are generated from it.

Scope	Field	Default	`.pen` default, if different
every node but instance	`visible`, `opacity`, `rotation`, `flipX` / `flipY`, `blend`	`true`, `1`, `0`, `false`, `"normal"`
every node	`position`, `locked`, `component`	`"auto"`, `false`, `false`
frame	`layout`	absent = no flex layout	`layout: horizontal` (importer writes `dir: "row"`)
frame	`w` / `h`	`{ "mode": "fit" }`	`fit_content`
frame	`clip`, `radius`	`false`, `0`
rect, polygon, browser	`radius`	`0`
polygon `star`	`ratio`	`0.38`
ellipse	`innerRadius`, `startAngle`, `sweepAngle`	`0`, `0`, `360`
path	`fillRule`	`"nonzero"`
text	`grow`	`"auto"`
text	`style.lineHeight`	absent = the font's default	same
script	`clip`	`false`
browser	`zoom`, `scrollX`, `scrollY`	`1`, `0`, `0`
layout	`gap`, `crossGap`, `pad`	`0`	gap 0; padding undocumented
layout	`justify`, `align`	`"start"`
layout	`wrap`, `includeStroke`	`false`
Size `fill`	`fallback` / `weight`	none / `1`
stroke	`width`, `align`, `cap`, `join`, `miterLimit`	`1`, `"inside"`, `"butt"`, `"miter"`, `4`	(to be checked by the importer)
solid paint	`blend`, `visible`	`"normal"`, `true`
gradient	`center`, `size`, `rotation`, `interpolation`, `opacity`, `blend`, `visible`	`[0.5,0.5]`, `[1,1]`, `0`, `"srgb"`, `1`, `"normal"`, `true`
image paint	`fit`, `opacity`, `blend`, `visible`	`"cover"`, `1`, `"normal"`, `true`	`cover`
shadow	`inner`, `spread`, `blend`, `visible`	`false`, `0`, `"normal"`, `true`
blur, backdrop-blur	`visible`	`true`
OKLCH / P3 color	`alpha`	`1`

every node but instance

Field visible, opacity, rotation, flipX / flipY, blend

Default true, 1, 0, false, "normal"

.pen default, if different

every node

Field position, locked, component

Default "auto", false, false

.pen default, if different

frame

Field layout

Default absent = no flex layout

.pen default, if different layout: horizontal (importer writes dir: "row")

frame

Field w / h

Default { "mode": "fit" }

.pen default, if different fit_content

frame

Field clip, radius

Default false, 0

.pen default, if different

rect, polygon, browser

Field radius

Default 0

.pen default, if different

polygon star

Field ratio

Default 0.38

.pen default, if different

ellipse

Field innerRadius, startAngle, sweepAngle

Default 0, 0, 360

.pen default, if different

path

Field fillRule

Default "nonzero"

.pen default, if different

text

Field grow

Default "auto"

.pen default, if different

text

Field style.lineHeight

Default absent = the font's default

.pen default, if different same

script

Field clip

Default false

.pen default, if different

browser

Field zoom, scrollX, scrollY

Default 1, 0, 0

.pen default, if different

layout

Field gap, crossGap, pad

Default 0

.pen default, if different gap 0; padding undocumented

layout

Field justify, align

Default "start"

.pen default, if different

layout

Field wrap, includeStroke

Default false

.pen default, if different

Size fill

Field fallback / weight

Default none / 1

.pen default, if different

stroke

Field width, align, cap, join, miterLimit

Default 1, "inside", "butt", "miter", 4

.pen default, if different (to be checked by the importer)

solid paint

Field blend, visible

Default "normal", true

.pen default, if different

gradient

Field center, size, rotation, interpolation, opacity, blend, visible

Default [0.5,0.5], [1,1], 0, "srgb", 1, "normal", true

.pen default, if different

image paint

Field fit, opacity, blend, visible

Default "cover", 1, "normal", true

.pen default, if different cover

shadow

Field inner, spread, blend, visible

Default false, 0, "normal", true

.pen default, if different

blur, backdrop-blur

Field visible

Default true

.pen default, if different

OKLCH / P3 color

Field alpha

Default 1

.pen default, if different

Not defaulted: x and y (absent means 0, but an explicit 0 is kept so positions stay visible in diffs), and every field without a row above.

Where defaults do not apply. The top-level keys of an instance's props and of a set override are never omitted or filled in, because there they override a component value (opacity: 1 restores full opacity over a component's 0.5). Values nested below those keys are normalized, because each such value replaces the target's value wholesale.

Keywords:

MUST

MUST NOT

SHOULD

MAY

set in small mono caps wherever they are normative