diff --git a/tests/e2e/keyboard/shortcuts.spec.ts b/tests/e2e/keyboard/shortcuts.spec.ts
index 70a0cbfff..873ca2ee1 100644
--- a/tests/e2e/keyboard/shortcuts.spec.ts
+++ b/tests/e2e/keyboard/shortcuts.spec.ts
@@ -1,5 +1,6 @@
 import { expect, test, type Page } from '@playwright/test'
 
+import { expectDefined } from '#tests/helpers/assert'
 import { CanvasHelper } from '#tests/helpers/canvas'
 
 let page: Page
@@ -19,11 +20,19 @@ test.afterAll(async () => {
 })
 
 function getActiveTool() {
-  return page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.activeTool)
+  return page.evaluate(() => {
+    const store = window.__OPEN_PENCIL_STORE__
+    if (!store) throw new Error('OpenPencil store not initialized')
+    return store.state.activeTool
+  })
 }
 
 function getSelectedCount() {
-  return page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.selectedIds.size)
+  return page.evaluate(() => {
+    const store = window.__OPEN_PENCIL_STORE__
+    if (!store) throw new Error('OpenPencil store not initialized')
+    return store.state.selectedIds.size
+  })
 }
 
 function getPageChildren() {
@@ -40,7 +49,19 @@ function getPageChildren() {
 }
 
 function getUIVisible() {
-  return page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.showUI)
+  return page.evaluate(() => {
+    const store = window.__OPEN_PENCIL_STORE__
+    if (!store) throw new Error('OpenPencil store not initialized')
+    return store.state.showUI
+  })
+}
+
+function getZoom() {
+  return page.evaluate(() => {
+    const store = window.__OPEN_PENCIL_STORE__
+    if (!store) throw new Error('OpenPencil store not initialized')
+    return store.state.zoom
+  })
 }
 
 test.describe('tool switching', () => {
@@ -125,11 +146,13 @@ test.describe('z-order shortcuts', () => {
     await canvas.drawRect(100, 100, 60, 60)
 
     const childrenBefore = await getPageChildren()
-    const firstId = childrenBefore[0].id
+    const firstId = expectDefined(childrenBefore[0], 'first page child').id
 
     // Select the first (bottom) node
     await page.evaluate((id) => {
-      window.__OPEN_PENCIL_STORE__!.select([id])
+      const store = window.__OPEN_PENCIL_STORE__
+      if (!store) throw new Error('OpenPencil store not initialized')
+      store.select([id])
     }, firstId)
     await canvas.waitForRender()
 
@@ -142,11 +165,13 @@ test.describe('z-order shortcuts', () => {
 
   test('[ sends to back', async () => {
     const children = await getPageChildren()
-    const lastId = children[children.length - 1].id
+    const lastId = expectDefined(children.at(-1), 'last page child').id
 
     // Select the last (top) node
     await page.evaluate((id) => {
-      window.__OPEN_PENCIL_STORE__!.select([id])
+      const store = window.__OPEN_PENCIL_STORE__
+      if (!store) throw new Error('OpenPencil store not initialized')
+      store.select([id])
     }, lastId)
     await canvas.waitForRender()
 
@@ -169,7 +194,7 @@ test.describe('group/ungroup shortcuts', () => {
     const children = await getPageChildren()
     const group = children.find((c) => c.type === 'GROUP')
     expect(group).toBeTruthy()
-    expect(group!.childIds.length).toBeGreaterThanOrEqual(2)
+    expect(group?.childIds.length).toBeGreaterThanOrEqual(2)
   })
 
   test('⌘⇧G ungroups', async () => {
@@ -229,7 +254,7 @@ test.describe('zoom shortcuts', () => {
     await page.keyboard.press('Meta+0')
     await canvas.waitForRender()
 
-    const zoomAfter = await page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.zoom)
+    const zoomAfter = await getZoom()
     expect(zoomAfter).toBe(1)
   })
 
@@ -237,7 +262,7 @@ test.describe('zoom shortcuts', () => {
     await page.keyboard.press('Meta+1')
     await canvas.waitForRender()
 
-    const zoom = await page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.zoom)
+    const zoom = await getZoom()
     expect(zoom).toBeGreaterThan(0)
     expect(zoom).toBeLessThanOrEqual(1)
   })
@@ -248,7 +273,7 @@ test.describe('zoom shortcuts', () => {
     await page.keyboard.press('Meta+2')
     await canvas.waitForRender()
 
-    const zoom = await page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.zoom)
+    const zoom = await getZoom()
     expect(zoom).toBeGreaterThan(0)
     expect(zoom).toBeLessThanOrEqual(1)
   })
@@ -257,7 +282,7 @@ test.describe('zoom shortcuts', () => {
     await page.keyboard.press('Shift+1')
     await canvas.waitForRender()
 
-    const zoom = await page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.zoom)
+    const zoom = await getZoom()
     expect(zoom).toBeGreaterThan(0)
     expect(zoom).toBeLessThanOrEqual(1)
   })
@@ -268,7 +293,7 @@ test.describe('zoom shortcuts', () => {
     await page.keyboard.press('Shift+2')
     await canvas.waitForRender()
 
-    const zoom = await page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.zoom)
+    const zoom = await getZoom()
     expect(zoom).toBeGreaterThan(0)
     expect(zoom).toBeLessThanOrEqual(1)
   })
diff --git a/tests/e2e/text/editing.spec.ts b/tests/e2e/text/editing.spec.ts
index d3e0eae23..7016e9184 100644
--- a/tests/e2e/text/editing.spec.ts
+++ b/tests/e2e/text/editing.spec.ts
@@ -1,5 +1,6 @@
 import { expect, test, type Page } from '@playwright/test'
 
+import { expectDefined } from '#tests/helpers/assert'
 import { CanvasHelper } from '#tests/helpers/canvas'
 
 let page: Page
@@ -55,7 +56,11 @@ function getPageChildren() {
 test('pressing T activates text tool', async () => {
   await page.keyboard.press('t')
 
-  const tool = await page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.activeTool)
+  const tool = await page.evaluate(() => {
+    const store = window.__OPEN_PENCIL_STORE__
+    if (!store) throw new Error('OpenPencil store not initialized')
+    return store.state.activeTool
+  })
   expect(tool).toBe('TEXT')
 })
 
@@ -73,8 +78,7 @@ test('clicking with text tool creates a text node', async () => {
 
 test('text node is selected after creation', async () => {
   const node = await getSelectedNode()
-  expect(node).toBeTruthy()
-  expect(node!.type).toBe('TEXT')
+  expect(node?.type).toBe('TEXT')
 })
 
 test('typography section appears for text node', async () => {
@@ -92,9 +96,8 @@ test('typography section appears for text node', async () => {
 
 test('text node has default font properties', async () => {
   const node = await getSelectedNode()
-  expect(node).toBeTruthy()
-  expect(node!.fontSize).toBeGreaterThan(0)
-  expect(node!.fontFamily).toBeTruthy()
+  expect(node?.fontSize).toBeGreaterThan(0)
+  expect(node?.fontFamily).toBeTruthy()
 })
 
 test('creating text via store works', async () => {
@@ -111,8 +114,8 @@ test('creating text via store works', async () => {
   await canvas.waitForRender()
 
   const node = await getSelectedNode()
-  expect(node!.text).toBe('Hello World')
-  expect(node!.fontSize).toBe(24)
+  expect(node?.text).toBe('Hello World')
+  expect(node?.fontSize).toBe(24)
 })
 
 test('undo removes text node', async () => {
@@ -130,10 +133,10 @@ test('frame tool creates FRAME node', async () => {
   await canvas.drag(400, 100, 600, 250)
   await canvas.waitForRender()
 
-  const node = await getSelectedNode()
-  expect(node!.type).toBe('FRAME')
-  expect(node!.width).toBeGreaterThan(0)
-  expect(node!.height).toBeGreaterThan(0)
+  const node = expectDefined(await getSelectedNode(), 'selected frame')
+  expect(node.type).toBe('FRAME')
+  expect(node.width).toBeGreaterThan(0)
+  expect(node.height).toBeGreaterThan(0)
 
   canvas.assertNoErrors()
 })
@@ -154,13 +157,17 @@ test('Enter key opens text editing and selects all without erasing', async () =>
   await canvas.waitForRender()
 
   const before = await getSelectedNode()
-  expect(before!.text).toBe('Keep this text')
-  expect(before!.type).toBe('TEXT')
+  expect(before?.text).toBe('Keep this text')
+  expect(before?.type).toBe('TEXT')
 
   await page.keyboard.press('Enter')
   await page.waitForTimeout(200)
 
-  const editing = await page.evaluate(() => window.__OPEN_PENCIL_STORE__!.state.editingTextId)
+  const editing = await page.evaluate(() => {
+    const store = window.__OPEN_PENCIL_STORE__
+    if (!store) throw new Error('OpenPencil store not initialized')
+    return store.state.editingTextId
+  })
   expect(editing).toBe(textId)
 
   const after = await page.evaluate(() => {
diff --git a/tests/engine/fig/import/legacy.test.ts b/tests/engine/fig/import/legacy.test.ts
index 4a5e2e3df..67b113f80 100644
--- a/tests/engine/fig/import/legacy.test.ts
+++ b/tests/engine/fig/import/legacy.test.ts
@@ -2,6 +2,8 @@ import { describe, test, expect } from 'bun:test'
 
 import { importNodeChanges, type NodeChange } from '@open-pencil/core'
 
+import { expectDefined } from '#tests/helpers/assert'
+
 function doc(): NodeChange {
   return {
     guid: { sessionID: 0, localID: 0 },
@@ -125,8 +127,9 @@ describe('fig-import: gradient fills', () => {
     expect(n.fills).toHaveLength(1)
     expect(n.fills[0].type).toBe('GRADIENT_LINEAR')
     expect(n.fills[0].gradientStops).toHaveLength(2)
-    expect(n.fills[0].gradientStops![0].color.r).toBe(1)
-    expect(n.fills[0].gradientStops![1].color.b).toBe(1)
+    const gradientStops = expectDefined(n.fills[0].gradientStops, 'linear gradient stops')
+    expect(gradientStops[0]?.color.r).toBe(1)
+    expect(gradientStops[1]?.color.b).toBe(1)
     expect(n.fills[0].gradientTransform).toBeDefined()
   })
 
@@ -182,7 +185,7 @@ describe('fig-import: image fills', () => {
     const n = graph.getChildren(graph.getPages()[0].id)[0]
     expect(n.fills[0].type).toBe('IMAGE')
     expect(n.fills[0].imageHash).toBeDefined()
-    expect(n.fills[0].imageHash!.length).toBe(40)
+    expect(n.fills[0].imageHash?.length).toBe(40)
     expect(n.fills[0].imageScaleMode).toBe('FILL')
   })
 
@@ -350,9 +353,10 @@ describe('fig-import: arc data', () => {
     ])
     const n = graph.getChildren(graph.getPages()[0].id)[0]
     expect(n.arcData).toBeDefined()
-    expect(n.arcData!.startingAngle).toBe(0)
-    expect(n.arcData!.endingAngle).toBeCloseTo(Math.PI)
-    expect(n.arcData!.innerRadius).toBe(0)
+    const arcData = expectDefined(n.arcData, 'ellipse arc data')
+    expect(arcData.startingAngle).toBe(0)
+    expect(arcData.endingAngle).toBeCloseTo(Math.PI)
+    expect(arcData.innerRadius).toBe(0)
   })
 
   test('donut (inner radius)', () => {
@@ -368,7 +372,7 @@ describe('fig-import: arc data', () => {
       } as Partial<NodeChange>)
     ])
     const n = graph.getChildren(graph.getPages()[0].id)[0]
-    expect(n.arcData!.innerRadius).toBe(0.5)
+    expect(n.arcData?.innerRadius).toBe(0.5)
   })
 })
 
@@ -554,13 +558,19 @@ describe('fig-import: variable asset refs', () => {
       })
     ])
 
-    const primary = [...graph.variables.values()].find((v) => v.name === 'Primary')!
-    const resolved = graph.resolveColorVariable(primary.id)!
+    const primary = expectDefined(
+      [...graph.variables.values()].find((v) => v.name === 'Primary'),
+      'Primary variable'
+    )
+    const resolved = expectDefined(graph.resolveColorVariable(primary.id), 'resolved Primary color')
     expect(resolved.r).toBeCloseTo(0.14)
     expect(resolved.g).toBeCloseTo(0.39)
     expect(resolved.b).toBeCloseTo(0.92)
 
-    const text = [...graph.getAllNodes()].find((n) => n.type === 'TEXT' && n.text === 'browse')!
+    const text = expectDefined(
+      [...graph.getAllNodes()].find((n) => n.type === 'TEXT' && n.text === 'browse'),
+      'browse text node'
+    )
     expect(text.fills[0].color.r).toBeCloseTo(0.14)
     expect(text.fills[0].color.g).toBeCloseTo(0.39)
     expect(text.fills[0].color.b).toBeCloseTo(0.92)