diff --git a/lint/plugin.js b/lint/plugin.js
index 20e00108d..183d0e2cf 100644
--- a/lint/plugin.js
+++ b/lint/plugin.js
@@ -1167,6 +1167,20 @@ const noTopLevelPrefixedTestFiles = createProgramFilenameRule({
   }
 })
 
+const noSiblingDomainPrefixedTestFiles = createProgramFilenameRule({
+  description: 'Disallow test files that repeat an existing sibling domain folder as a filename prefix',
+  check(file) {
+    const match = file.match(/^(.*\/tests\/(?:engine|e2e)\/.+\/)([^/]+)-[^/]+\.(?:test|spec)\.ts$/)
+    if (!match) return false
+
+    const [, dir, prefix] = match
+    if (!existsSync(`${dir}${prefix}`)) return false
+
+    const filename = file.slice(dir.length)
+    return `Move '${filename}' under the existing '${prefix}/' folder instead of repeating the domain as a filename prefix.`
+  }
+})
+
 const noFlatKiwiModules = createProgramFilenameRule({
   description: 'Disallow flat top-level Kiwi modules — group code under Kiwi subdomains',
   check(file) {
@@ -1228,7 +1242,8 @@ const plugin = {
     'no-useless-pass-through-wrappers': noUselessPassThroughWrappers,
     'no-function-alias-imports': noFunctionAliasImports,
     'no-flat-kiwi-modules': noFlatKiwiModules,
-    'no-top-level-prefixed-test-files': noTopLevelPrefixedTestFiles
+    'no-top-level-prefixed-test-files': noTopLevelPrefixedTestFiles,
+    'no-sibling-domain-prefixed-test-files': noSiblingDomainPrefixedTestFiles
   }
 }
 
diff --git a/oxlint.json b/oxlint.json
index 4b05b1910..31510bc81 100644
--- a/oxlint.json
+++ b/oxlint.json
@@ -154,7 +154,8 @@
     "open-pencil/non-component-source-directories-kebab-case": "error",
     "open-pencil/no-component-root-sibling-folder": "error",
     "open-pencil/no-flat-kiwi-modules": "error",
-    "open-pencil/no-top-level-prefixed-test-files": "error"
+    "open-pencil/no-top-level-prefixed-test-files": "error",
+    "open-pencil/no-sibling-domain-prefixed-test-files": "error"
   },
   "overrides": [
     {
diff --git a/tests/engine/editor/clipboard/import-nodes/text-metrics.test.ts b/tests/engine/editor/clipboard/import-nodes/text/metrics.test.ts
similarity index 100%
rename from tests/engine/editor/clipboard/import-nodes/text-metrics.test.ts
rename to tests/engine/editor/clipboard/import-nodes/text/metrics.test.ts
diff --git a/tests/engine/editor/clipboard/import-nodes/undo-redo.test.ts b/tests/engine/editor/clipboard/import-nodes/undo/redo.test.ts
similarity index 100%
rename from tests/engine/editor/clipboard/import-nodes/undo-redo.test.ts
rename to tests/engine/editor/clipboard/import-nodes/undo/redo.test.ts
diff --git a/tests/engine/fig/import/legacy/arc-data.test.ts b/tests/engine/fig/import/legacy/arc/data.test.ts
similarity index 96%
rename from tests/engine/fig/import/legacy/arc-data.test.ts
rename to tests/engine/fig/import/legacy/arc/data.test.ts
index abde7c4d1..6306fdbd1 100644
--- a/tests/engine/fig/import/legacy/arc-data.test.ts
+++ b/tests/engine/fig/import/legacy/arc/data.test.ts
@@ -4,7 +4,7 @@ import { importNodeChanges } from '@open-pencil/core'
 
 import { expectDefined } from '#tests/helpers/assert'
 
-import { canvas, doc, node } from './helpers'
+import { canvas, doc, node } from '../helpers'
 
 describe('fig-import: arc data', () => {
   test('partial ellipse', () => {
diff --git a/tests/engine/fig/import/legacy/auto-layout.test.ts b/tests/engine/fig/import/legacy/auto-layout/basic.test.ts
similarity index 92%
rename from tests/engine/fig/import/legacy/auto-layout.test.ts
rename to tests/engine/fig/import/legacy/auto-layout/basic.test.ts
index ac50e8f46..8e07a5ade 100644
--- a/tests/engine/fig/import/legacy/auto-layout.test.ts
+++ b/tests/engine/fig/import/legacy/auto-layout/basic.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { importNodeChanges } from '@open-pencil/core'
 
-import { canvas, doc, node } from './helpers'
+import { canvas, doc, node } from '../helpers'
 
 describe('fig-import: auto-layout alignment', () => {
   test('maps SPACE_EVENLY kiwi primary alignment to Figma space-between', () => {
diff --git a/tests/engine/fig/import/legacy/blend-mode.test.ts b/tests/engine/fig/import/legacy/blend/mode.test.ts
similarity index 93%
rename from tests/engine/fig/import/legacy/blend-mode.test.ts
rename to tests/engine/fig/import/legacy/blend/mode.test.ts
index eebae4146..577f0a7d3 100644
--- a/tests/engine/fig/import/legacy/blend-mode.test.ts
+++ b/tests/engine/fig/import/legacy/blend/mode.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { importNodeChanges } from '@open-pencil/core'
 
-import { canvas, doc, node } from './helpers'
+import { canvas, doc, node } from '../helpers'
 
 describe('fig-import: blend mode', () => {
   test('node blend mode', () => {
diff --git a/tests/engine/fig/import/legacy/clips-content.test.ts b/tests/engine/fig/import/legacy/clips/content.test.ts
similarity index 96%
rename from tests/engine/fig/import/legacy/clips-content.test.ts
rename to tests/engine/fig/import/legacy/clips/content.test.ts
index 3ac662e9c..cdc3a7bfa 100644
--- a/tests/engine/fig/import/legacy/clips-content.test.ts
+++ b/tests/engine/fig/import/legacy/clips/content.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { importNodeChanges } from '@open-pencil/core'
 
-import { canvas, doc, node } from './helpers'
+import { canvas, doc, node } from '../helpers'
 
 describe('fig-import: clipsContent with resizeToFit', () => {
   test('regular FRAME with frameMaskDisabled=false clips content', () => {
diff --git a/tests/engine/fig/import/legacy/component-sets.test.ts b/tests/engine/fig/import/legacy/component/sets.test.ts
similarity index 97%
rename from tests/engine/fig/import/legacy/component-sets.test.ts
rename to tests/engine/fig/import/legacy/component/sets.test.ts
index 604255f2b..a7f03963c 100644
--- a/tests/engine/fig/import/legacy/component-sets.test.ts
+++ b/tests/engine/fig/import/legacy/component/sets.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { importNodeChanges } from '@open-pencil/core'
 
-import { canvas, doc, node } from './helpers'
+import { canvas, doc, node } from '../helpers'
 
 describe('fig-import: component set detection', () => {
   test('FRAME with VARIANT componentPropDefs becomes COMPONENT_SET', () => {
diff --git a/tests/engine/fig/import/legacy/image-fills.test.ts b/tests/engine/fig/import/legacy/image/fills.test.ts
similarity index 96%
rename from tests/engine/fig/import/legacy/image-fills.test.ts
rename to tests/engine/fig/import/legacy/image/fills.test.ts
index cf93f5aba..11dd0bbe9 100644
--- a/tests/engine/fig/import/legacy/image-fills.test.ts
+++ b/tests/engine/fig/import/legacy/image/fills.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { importNodeChanges } from '@open-pencil/core'
 
-import { canvas, doc, node } from './helpers'
+import { canvas, doc, node } from '../helpers'
 
 describe('fig-import: image fills', () => {
   test('image fill with hash', () => {
diff --git a/tests/engine/fig/import/legacy/independent-strokes.test.ts b/tests/engine/fig/import/legacy/independent/strokes.test.ts
similarity index 93%
rename from tests/engine/fig/import/legacy/independent-strokes.test.ts
rename to tests/engine/fig/import/legacy/independent/strokes.test.ts
index d2e73b43f..6890533cb 100644
--- a/tests/engine/fig/import/legacy/independent-strokes.test.ts
+++ b/tests/engine/fig/import/legacy/independent/strokes.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { importNodeChanges } from '@open-pencil/core'
 
-import { canvas, doc, node } from './helpers'
+import { canvas, doc, node } from '../helpers'
 
 describe('fig-import: independent stroke weights', () => {
   test('border weights imported', () => {
diff --git a/tests/engine/fig/import/legacy/multiple-fills.test.ts b/tests/engine/fig/import/legacy/multiple/fills.test.ts
similarity index 96%
rename from tests/engine/fig/import/legacy/multiple-fills.test.ts
rename to tests/engine/fig/import/legacy/multiple/fills.test.ts
index 9018dc8b7..c0fe4c277 100644
--- a/tests/engine/fig/import/legacy/multiple-fills.test.ts
+++ b/tests/engine/fig/import/legacy/multiple/fills.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { importNodeChanges } from '@open-pencil/core'
 
-import { canvas, doc, node } from './helpers'
+import { canvas, doc, node } from '../helpers'
 
 describe('fig-import: multiple fills', () => {
   test('solid + gradient stacked', () => {
diff --git a/tests/engine/fig/import/legacy/node-types.test.ts b/tests/engine/fig/import/legacy/node/types.test.ts
similarity index 96%
rename from tests/engine/fig/import/legacy/node-types.test.ts
rename to tests/engine/fig/import/legacy/node/types.test.ts
index 78c157454..beb1ab4ab 100644
--- a/tests/engine/fig/import/legacy/node-types.test.ts
+++ b/tests/engine/fig/import/legacy/node/types.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { importNodeChanges } from '@open-pencil/core'
 
-import { canvas, doc, node } from './helpers'
+import { canvas, doc, node } from '../helpers'
 
 describe('fig-import: node types', () => {
   test('ROUNDED_RECTANGLE imported as its own type', () => {
diff --git a/tests/engine/figma/api/absolute-position.test.ts b/tests/engine/figma/api/absolute/position.test.ts
similarity index 93%
rename from tests/engine/figma/api/absolute-position.test.ts
rename to tests/engine/figma/api/absolute/position.test.ts
index 28e19dcbd..f93e0dc9f 100644
--- a/tests/engine/figma/api/absolute-position.test.ts
+++ b/tests/engine/figma/api/absolute/position.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('absolute position', () => {
   test('absoluteBoundingBox accounts for nesting', () => {
diff --git a/tests/engine/figma/api/auto-layout.test.ts b/tests/engine/figma/api/auto-layout/basic.test.ts
similarity index 97%
rename from tests/engine/figma/api/auto-layout.test.ts
rename to tests/engine/figma/api/auto-layout/basic.test.ts
index ceba3f060..92d4bf700 100644
--- a/tests/engine/figma/api/auto-layout.test.ts
+++ b/tests/engine/figma/api/auto-layout/basic.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('auto-layout', () => {
   test('layoutMode', () => {
diff --git a/tests/engine/figma/api/auto-layout-extras.test.ts b/tests/engine/figma/api/auto-layout/extras.test.ts
similarity index 97%
rename from tests/engine/figma/api/auto-layout-extras.test.ts
rename to tests/engine/figma/api/auto-layout/extras.test.ts
index 63d755430..8989231ed 100644
--- a/tests/engine/figma/api/auto-layout-extras.test.ts
+++ b/tests/engine/figma/api/auto-layout/extras.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('auto-layout extras', () => {
   test('primaryAxisSizingMode maps FIXED/AUTO', () => {
diff --git a/tests/engine/figma/api/corner-radius.test.ts b/tests/engine/figma/api/corner/radius.test.ts
similarity index 93%
rename from tests/engine/figma/api/corner-radius.test.ts
rename to tests/engine/figma/api/corner/radius.test.ts
index c188666da..a8c3ffb5f 100644
--- a/tests/engine/figma/api/corner-radius.test.ts
+++ b/tests/engine/figma/api/corner/radius.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('corner radius', () => {
   test('uniform corner radius', () => {
diff --git a/tests/engine/figma/api/create-component-from-node.test.ts b/tests/engine/figma/api/create/component-from-node.test.ts
similarity index 94%
rename from tests/engine/figma/api/create-component-from-node.test.ts
rename to tests/engine/figma/api/create/component-from-node.test.ts
index 2dafc957f..6180763df 100644
--- a/tests/engine/figma/api/create-component-from-node.test.ts
+++ b/tests/engine/figma/api/create/component-from-node.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('createComponentFromNode', () => {
   test('converts frame to component', () => {
diff --git a/tests/engine/figma/api/document-and-pages.test.ts b/tests/engine/figma/api/document/pages.test.ts
similarity index 97%
rename from tests/engine/figma/api/document-and-pages.test.ts
rename to tests/engine/figma/api/document/pages.test.ts
index cd641c6e5..972c40db7 100644
--- a/tests/engine/figma/api/document-and-pages.test.ts
+++ b/tests/engine/figma/api/document/pages.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { expectDefined } from '#tests/helpers/assert'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('document & pages', () => {
   test('root has pages as children', () => {
diff --git a/tests/engine/figma/api/find-all-with-criteria.test.ts b/tests/engine/figma/api/find/all-with-criteria.test.ts
similarity index 94%
rename from tests/engine/figma/api/find-all-with-criteria.test.ts
rename to tests/engine/figma/api/find/all-with-criteria.test.ts
index 4e8c1c1a0..c0f01bcb6 100644
--- a/tests/engine/figma/api/find-all-with-criteria.test.ts
+++ b/tests/engine/figma/api/find/all-with-criteria.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('findAllWithCriteria', () => {
   test('filters by type', () => {
diff --git a/tests/engine/figma/api/frozen-arrays.test.ts b/tests/engine/figma/api/frozen/arrays.test.ts
similarity index 95%
rename from tests/engine/figma/api/frozen-arrays.test.ts
rename to tests/engine/figma/api/frozen/arrays.test.ts
index aa12e6bfd..b883c0c20 100644
--- a/tests/engine/figma/api/frozen-arrays.test.ts
+++ b/tests/engine/figma/api/frozen/arrays.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { type Fill } from '@open-pencil/core'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('frozen arrays', () => {
   test('fills returns frozen clone', () => {
diff --git a/tests/engine/figma/api/internals-not-exposed.test.ts b/tests/engine/figma/api/internals/not-exposed.test.ts
similarity index 89%
rename from tests/engine/figma/api/internals-not-exposed.test.ts
rename to tests/engine/figma/api/internals/not-exposed.test.ts
index f320822aa..67e2daf15 100644
--- a/tests/engine/figma/api/internals-not-exposed.test.ts
+++ b/tests/engine/figma/api/internals/not-exposed.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('internals not exposed', () => {
   test('node has no _id, _graph, _api properties', () => {
diff --git a/tests/engine/figma/api/layout-sizing.test.ts b/tests/engine/figma/api/layout/sizing.test.ts
similarity index 98%
rename from tests/engine/figma/api/layout-sizing.test.ts
rename to tests/engine/figma/api/layout/sizing.test.ts
index 165cf16cf..d82c72db9 100644
--- a/tests/engine/figma/api/layout-sizing.test.ts
+++ b/tests/engine/figma/api/layout/sizing.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { getNodeOrThrow } from '#tests/helpers/assert'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('layout sizing', () => {
   test('child in horizontal parent: h=primary, v=counter', () => {
diff --git a/tests/engine/figma/api/min-max-dimensions.test.ts b/tests/engine/figma/api/min-max/dimensions.test.ts
similarity index 95%
rename from tests/engine/figma/api/min-max-dimensions.test.ts
rename to tests/engine/figma/api/min-max/dimensions.test.ts
index 0689a3308..3d3dd1c77 100644
--- a/tests/engine/figma/api/min-max-dimensions.test.ts
+++ b/tests/engine/figma/api/min-max/dimensions.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('min/max dimensions', () => {
   test('defaults to null', () => {
diff --git a/tests/engine/figma/api/node-creation.test.ts b/tests/engine/figma/api/node/creation.test.ts
similarity index 97%
rename from tests/engine/figma/api/node-creation.test.ts
rename to tests/engine/figma/api/node/creation.test.ts
index deb5be762..a4e10a561 100644
--- a/tests/engine/figma/api/node-creation.test.ts
+++ b/tests/engine/figma/api/node/creation.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { expectDefined } from '#tests/helpers/assert'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('node creation', () => {
   test('createFrame', () => {
diff --git a/tests/engine/figma/api/property-access.test.ts b/tests/engine/figma/api/property/access.test.ts
similarity index 97%
rename from tests/engine/figma/api/property-access.test.ts
rename to tests/engine/figma/api/property/access.test.ts
index d666ea8dc..70f690c22 100644
--- a/tests/engine/figma/api/property-access.test.ts
+++ b/tests/engine/figma/api/property/access.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('property access', () => {
   test('name get/set', () => {
diff --git a/tests/engine/figma/api/stroke-details.test.ts b/tests/engine/figma/api/stroke/details.test.ts
similarity index 97%
rename from tests/engine/figma/api/stroke-details.test.ts
rename to tests/engine/figma/api/stroke/details.test.ts
index 4212e0545..db62d33b1 100644
--- a/tests/engine/figma/api/stroke-details.test.ts
+++ b/tests/engine/figma/api/stroke/details.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('stroke details', () => {
   test('strokeWeight and strokeAlign', () => {
diff --git a/tests/engine/figma/api/text.test.ts b/tests/engine/figma/api/text/basic.test.ts
similarity index 97%
rename from tests/engine/figma/api/text.test.ts
rename to tests/engine/figma/api/text/basic.test.ts
index bd29abb5c..f318b914e 100644
--- a/tests/engine/figma/api/text.test.ts
+++ b/tests/engine/figma/api/text/basic.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('text', () => {
   test('characters maps to text content', () => {
diff --git a/tests/engine/figma/api/text-extras.test.ts b/tests/engine/figma/api/text/extras.test.ts
similarity index 96%
rename from tests/engine/figma/api/text-extras.test.ts
rename to tests/engine/figma/api/text/extras.test.ts
index 12dceb140..02482ba08 100644
--- a/tests/engine/figma/api/text-extras.test.ts
+++ b/tests/engine/figma/api/text/extras.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('text extras', () => {
   test('textTruncation', () => {
diff --git a/tests/engine/figma/api/tree-operations.test.ts b/tests/engine/figma/api/tree/operations.test.ts
similarity index 96%
rename from tests/engine/figma/api/tree-operations.test.ts
rename to tests/engine/figma/api/tree/operations.test.ts
index f204646db..d90c46473 100644
--- a/tests/engine/figma/api/tree-operations.test.ts
+++ b/tests/engine/figma/api/tree/operations.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { expectDefined } from '#tests/helpers/assert'
 
-import { createAPI } from './helpers'
+import { createAPI } from '../helpers'
 
 describe('tree operations', () => {
   test('appendChild reparents', () => {
diff --git a/tests/engine/kiwi/serialize-fixes/auto-layout-transforms.test.ts b/tests/engine/kiwi/serialize-fixes/auto-layout/transforms.test.ts
similarity index 98%
rename from tests/engine/kiwi/serialize-fixes/auto-layout-transforms.test.ts
rename to tests/engine/kiwi/serialize-fixes/auto-layout/transforms.test.ts
index 0d6ef5695..e38b36c6e 100644
--- a/tests/engine/kiwi/serialize-fixes/auto-layout-transforms.test.ts
+++ b/tests/engine/kiwi/serialize-fixes/auto-layout/transforms.test.ts
@@ -4,7 +4,7 @@ import { SceneGraph, sceneNodeToKiwi } from '@open-pencil/core'
 
 import { expectDefined, getNodeOrThrow } from '#tests/helpers/assert'
 
-import { ROOT_GUID, pageId } from './helpers'
+import { ROOT_GUID, pageId } from '../helpers'
 
 describe('Fix 1: auto-layout child transforms', () => {
   test('auto-layout child gets zero transform regardless of its x/y', () => {
diff --git a/tests/engine/kiwi/serialize-fixes/borders-take-space.test.ts b/tests/engine/kiwi/serialize-fixes/borders/take-space.test.ts
similarity index 97%
rename from tests/engine/kiwi/serialize-fixes/borders-take-space.test.ts
rename to tests/engine/kiwi/serialize-fixes/borders/take-space.test.ts
index ff5a0717d..e06883018 100644
--- a/tests/engine/kiwi/serialize-fixes/borders-take-space.test.ts
+++ b/tests/engine/kiwi/serialize-fixes/borders/take-space.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, test } from 'bun:test'
 
 import { SceneGraph } from '@open-pencil/core'
 
-import { pageId, toKiwi } from './helpers'
+import { pageId, toKiwi } from '../helpers'
 
 describe('Fix 3: bordersTakeSpace serialization', () => {
   test('auto-layout frame with strokesIncludedInLayout=true gets bordersTakeSpace=true', () => {
diff --git a/tests/engine/kiwi/serialize-fixes/font-family.test.ts b/tests/engine/kiwi/serialize-fixes/font/family.test.ts
similarity index 98%
rename from tests/engine/kiwi/serialize-fixes/font-family.test.ts
rename to tests/engine/kiwi/serialize-fixes/font/family.test.ts
index 77c5d17b4..0f9159a39 100644
--- a/tests/engine/kiwi/serialize-fixes/font-family.test.ts
+++ b/tests/engine/kiwi/serialize-fixes/font/family.test.ts
@@ -4,7 +4,7 @@ import { exportFigFile, parseFigFile, SceneGraph } from '@open-pencil/core'
 
 import { expectDefined } from '#tests/helpers/assert'
 
-import { pageId, toKiwi } from './helpers'
+import { pageId, toKiwi } from '../helpers'
 
 describe('Fix 5: font family normalization in derivedTextData', () => {
   test('optical size suffix stripped in roundtrip', async () => {
diff --git a/tests/engine/kiwi/serialize-fixes/frame-mask.test.ts b/tests/engine/kiwi/serialize-fixes/frame/mask.test.ts
similarity index 98%
rename from tests/engine/kiwi/serialize-fixes/frame-mask.test.ts
rename to tests/engine/kiwi/serialize-fixes/frame/mask.test.ts
index e7ca73f14..2732fecbc 100644
--- a/tests/engine/kiwi/serialize-fixes/frame-mask.test.ts
+++ b/tests/engine/kiwi/serialize-fixes/frame/mask.test.ts
@@ -4,7 +4,7 @@ import { exportFigFile, parseFigFile, SceneGraph } from '@open-pencil/core'
 
 import { expectDefined } from '#tests/helpers/assert'
 
-import { pageId, toKiwi } from './helpers'
+import { pageId, toKiwi } from '../helpers'
 
 describe('Fix 2: frameMaskDisabled is inverse of clipsContent', () => {
   test('FRAME without clipsContent gets frameMaskDisabled=true', () => {
diff --git a/tests/engine/kiwi/serialize-fixes/line-height.test.ts b/tests/engine/kiwi/serialize-fixes/line/height.test.ts
similarity index 98%
rename from tests/engine/kiwi/serialize-fixes/line-height.test.ts
rename to tests/engine/kiwi/serialize-fixes/line/height.test.ts
index b378b9c96..aafbaa4a0 100644
--- a/tests/engine/kiwi/serialize-fixes/line-height.test.ts
+++ b/tests/engine/kiwi/serialize-fixes/line/height.test.ts
@@ -4,7 +4,7 @@ import { exportFigFile, parseFigFile, SceneGraph } from '@open-pencil/core'
 
 import { expectDefined } from '#tests/helpers/assert'
 
-import { pageId, toKiwi } from './helpers'
+import { pageId, toKiwi } from '../helpers'
 
 describe('Fix 4: text lineHeight serialization', () => {
   test('text node with explicit lineHeight uses that value', () => {
diff --git a/tests/engine/layout/auto-layout/absolute-children-in-yoga-tree.test.ts b/tests/engine/layout/auto-layout/absolute/children-in-yoga-tree.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/absolute-children-in-yoga-tree.test.ts
rename to tests/engine/layout/auto-layout/absolute/children-in-yoga-tree.test.ts
diff --git a/tests/engine/layout/auto-layout/absolute-positioning.test.ts b/tests/engine/layout/auto-layout/absolute/positioning.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/absolute-positioning.test.ts
rename to tests/engine/layout/auto-layout/absolute/positioning.test.ts
diff --git a/tests/engine/layout/auto-layout/alignment-counter-axis.test.ts b/tests/engine/layout/auto-layout/alignment/counter-axis.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/alignment-counter-axis.test.ts
rename to tests/engine/layout/auto-layout/alignment/counter-axis.test.ts
diff --git a/tests/engine/layout/auto-layout/alignment-primary-axis.test.ts b/tests/engine/layout/auto-layout/alignment/primary-axis.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/alignment-primary-axis.test.ts
rename to tests/engine/layout/auto-layout/alignment/primary-axis.test.ts
diff --git a/tests/engine/layout/auto-layout/counter-axis-align-content.test.ts b/tests/engine/layout/auto-layout/counter-axis/align-content.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/counter-axis-align-content.test.ts
rename to tests/engine/layout/auto-layout/counter-axis/align-content.test.ts
diff --git a/tests/engine/layout/auto-layout/counter-axis-spacing-no-wrap.test.ts b/tests/engine/layout/auto-layout/counter-axis/spacing-no-wrap.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/counter-axis-spacing-no-wrap.test.ts
rename to tests/engine/layout/auto-layout/counter-axis/spacing-no-wrap.test.ts
diff --git a/tests/engine/layout/auto-layout/fill-flex-basis.test.ts b/tests/engine/layout/auto-layout/fill/flex-basis.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/fill-flex-basis.test.ts
rename to tests/engine/layout/auto-layout/fill/flex-basis.test.ts
diff --git a/tests/engine/layout/auto-layout/gap-mapping-correctness.test.ts b/tests/engine/layout/auto-layout/gap/mapping-correctness.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/gap-mapping-correctness.test.ts
rename to tests/engine/layout/auto-layout/gap/mapping-correctness.test.ts
diff --git a/tests/engine/layout/auto-layout/hidden-children.test.ts b/tests/engine/layout/auto-layout/hidden-children/basic.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/hidden-children.test.ts
rename to tests/engine/layout/auto-layout/hidden-children/basic.test.ts
diff --git a/tests/engine/layout/auto-layout/hidden-children-preserve-dimensions.test.ts b/tests/engine/layout/auto-layout/hidden-children/preserve-dimensions.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/hidden-children-preserve-dimensions.test.ts
rename to tests/engine/layout/auto-layout/hidden-children/preserve-dimensions.test.ts
diff --git a/tests/engine/layout/auto-layout/horizontal-basic.test.ts b/tests/engine/layout/auto-layout/horizontal/basic.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/horizontal-basic.test.ts
rename to tests/engine/layout/auto-layout/horizontal/basic.test.ts
diff --git a/tests/engine/layout/auto-layout/layout-align-self-extended-values.test.ts b/tests/engine/layout/auto-layout/layout-align-self/extended-values.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/layout-align-self-extended-values.test.ts
rename to tests/engine/layout/auto-layout/layout-align-self/extended-values.test.ts
diff --git a/tests/engine/layout/auto-layout/layout-mode-none.test.ts b/tests/engine/layout/auto-layout/layout/mode-none.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/layout-mode-none.test.ts
rename to tests/engine/layout/auto-layout/layout/mode-none.test.ts
diff --git a/tests/engine/layout/auto-layout/min-max-constraints.test.ts b/tests/engine/layout/auto-layout/min-max/constraints.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/min-max-constraints.test.ts
rename to tests/engine/layout/auto-layout/min-max/constraints.test.ts
diff --git a/tests/engine/layout/auto-layout/mixed-sizing.test.ts b/tests/engine/layout/auto-layout/mixed/sizing.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/mixed-sizing.test.ts
rename to tests/engine/layout/auto-layout/mixed/sizing.test.ts
diff --git a/tests/engine/layout/auto-layout/nested-auto-layout.test.ts b/tests/engine/layout/auto-layout/nested/basic.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/nested-auto-layout.test.ts
rename to tests/engine/layout/auto-layout/nested/basic.test.ts
diff --git a/tests/engine/layout/auto-layout/nested-auto-layout-with-fill-children.test.ts b/tests/engine/layout/auto-layout/nested/fill-children.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/nested-auto-layout-with-fill-children.test.ts
rename to tests/engine/layout/auto-layout/nested/fill-children.test.ts
diff --git a/tests/engine/layout/auto-layout/self-alignment.test.ts b/tests/engine/layout/auto-layout/self/alignment.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/self-alignment.test.ts
rename to tests/engine/layout/auto-layout/self/alignment.test.ts
diff --git a/tests/engine/layout/auto-layout/sizing-modes.test.ts b/tests/engine/layout/auto-layout/sizing/modes.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/sizing-modes.test.ts
rename to tests/engine/layout/auto-layout/sizing/modes.test.ts
diff --git a/tests/engine/layout/auto-layout/text-measurement.test.ts b/tests/engine/layout/auto-layout/text/measurement.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/text-measurement.test.ts
rename to tests/engine/layout/auto-layout/text/measurement.test.ts
diff --git a/tests/engine/layout/auto-layout/vertical-basic.test.ts b/tests/engine/layout/auto-layout/vertical/basic.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/vertical-basic.test.ts
rename to tests/engine/layout/auto-layout/vertical/basic.test.ts
diff --git a/tests/engine/layout/auto-layout/wrap-layout.test.ts b/tests/engine/layout/auto-layout/wrap/layout.test.ts
similarity index 100%
rename from tests/engine/layout/auto-layout/wrap-layout.test.ts
rename to tests/engine/layout/auto-layout/wrap/layout.test.ts