diff --git a/packages/core/src/canvas/renderer/pipeline.ts b/packages/core/src/canvas/renderer/pipeline.ts
index 9611894ad..1bf43c78e 100644
--- a/packages/core/src/canvas/renderer/pipeline.ts
+++ b/packages/core/src/canvas/renderer/pipeline.ts
@@ -38,9 +38,6 @@ export function renderFromEditorState(
   dpr = 1,
   layer: RenderLayer = 'full'
 ): void {
-  const extendedState = state as EditorState & {
-    nodeEditState?: RenderOverlays['nodeEditState']
-  }
   r.dpr = dpr
   r.panX = state.panX
   r.panY = state.panY
@@ -72,7 +69,7 @@ export function renderFromEditorState(
             cursorY: state.penCursorY ?? undefined
           } as RenderOverlays['penState'])
         : null,
-      nodeEditState: extendedState.nodeEditState ?? null,
+      nodeEditState: state.nodeEditState ?? null,
       remoteCursors: state.remoteCursors
     },
     state.sceneVersion,
diff --git a/packages/core/src/editor/shapes/pen.ts b/packages/core/src/editor/shapes/pen.ts
index 6e97b006d..8a513b1e6 100644
--- a/packages/core/src/editor/shapes/pen.ts
+++ b/packages/core/src/editor/shapes/pen.ts
@@ -1,5 +1,5 @@
 import type { EditorContext } from '#core/editor/types'
-import type { Fill, SceneNode, VectorNetwork, VectorRegion, VectorSegment } from '#core/scene-graph'
+import type { SceneNode, VectorNetwork, VectorRegion, VectorSegment } from '#core/scene-graph'
 import type { Vector } from '#core/types'
 import { computeVectorBounds } from '#core/vector'
 
@@ -189,13 +189,9 @@ export function createPenActions(ctx: EditorContext, createShape: CreateShape) {
       regions: network.regions
     }
 
-    const penStyle = ps as typeof ps & {
-      resumedFills?: Fill[]
-      resumedStrokes?: SceneNode['strokes']
-    }
-    const fills = penStyle.resumedFills ? penStyle.resumedFills.map((f) => ({ ...f })) : []
-    const strokes = penStyle.resumedStrokes
-      ? penStyle.resumedStrokes.map((s) => ({ ...s }))
+    const fills = ps.resumedFills ? ps.resumedFills.map((f) => ({ ...f })) : []
+    const strokes = ps.resumedStrokes
+      ? ps.resumedStrokes.map((s) => ({ ...s }))
       : [{ ...PEN_DEFAULT_STROKE }]
 
     const nodeId = createShape('VECTOR', bounds.x, bounds.y, bounds.width, bounds.height)
diff --git a/packages/core/src/editor/types.ts b/packages/core/src/editor/types.ts
index 070e95891..35285a7aa 100644
--- a/packages/core/src/editor/types.ts
+++ b/packages/core/src/editor/types.ts
@@ -1,6 +1,7 @@
 import type { CanvasKit } from 'canvaskit-wasm'
 
 import type { RulerTheme, SkiaRenderer } from '#core/canvas/renderer'
+import type { RenderOverlays } from '#core/canvas/renderer/types'
 import type { SceneGraph, SceneNode, VectorSegment, VectorVertex } from '#core/scene-graph'
 import type { SnapGuide } from '#core/scene-graph/snap'
 import type { UndoManager } from '#core/scene-graph/undo'
@@ -45,6 +46,9 @@ export interface EditorState {
     oppositeDragTangent: Vector | null
     pendingClose?: boolean
     closingToFirst: boolean
+    resumingNodeId?: string
+    resumedFills?: SceneNode['fills']
+    resumedStrokes?: SceneNode['strokes']
   } | null
   penCursorX: number | null
   penCursorY: number | null
@@ -65,6 +69,9 @@ export interface EditorState {
   sceneVersion: number
   loading: boolean
   enteredContainerId: string | null
+  nodeEditState?: RenderOverlays['nodeEditState'] | null
+  cursorCanvasX?: number | null
+  cursorCanvasY?: number | null
 }
 
 export interface EditorEvents {
diff --git a/packages/core/src/lint/linter.ts b/packages/core/src/lint/linter.ts
index 5395cdc12..989162d04 100644
--- a/packages/core/src/lint/linter.ts
+++ b/packages/core/src/lint/linter.ts
@@ -17,7 +17,7 @@ export class Linter {
   private rules = new Map<string, Rule>()
   private ruleConfigs = new Map<string, { severity: Severity; options?: Record<string, unknown> }>()
   private messages: LintMessage[] = []
-  private nodes = new Map<string, LintNode & { parent?: LintNode }>()
+  private nodes = new Map<string, LintNode>()
 
   constructor(options: { config?: LintConfig; preset?: string; rules?: string[] } = {}) {
     let baseConfig: Record<
@@ -61,8 +61,8 @@ export class Linter {
     const raw = graph.getNode(id)
     if (!raw) return
     const node = this.toLintNode(raw)
-    ;(node as LintNode & { parent?: LintNode }).parent = parent
-    this.nodes.set(id, node as LintNode & { parent?: LintNode })
+    node.parent = parent
+    this.nodes.set(id, node)
     for (const childId of raw.childIds) this.capture(graph, childId, node)
   }
 
@@ -125,7 +125,7 @@ export class Linter {
             message,
             nodeId: node.id,
             nodeName: node.name,
-            nodePath: getNodePath(this.nodes.get(node.id) as LintNode & { parent?: LintNode }),
+            nodePath: getNodePath(this.nodes.get(node.id) ?? node),
             suggest
           })
         },
diff --git a/packages/core/src/lint/rules/no-hardcoded-colors.ts b/packages/core/src/lint/rules/no-hardcoded-colors.ts
index f419fa1bd..ba3dcedb3 100644
--- a/packages/core/src/lint/rules/no-hardcoded-colors.ts
+++ b/packages/core/src/lint/rules/no-hardcoded-colors.ts
@@ -19,7 +19,14 @@ export default defineRule({
     'INSTANCE'
   ],
   check(node, context) {
-    const checkPaints = (paints: typeof node.fills, field: 'fills' | 'strokes') => {
+    const checkPaints = (
+      paints: ReadonlyArray<{
+        visible: boolean
+        color?: { r: number; g: number; b: number }
+        type?: string
+      }>,
+      field: 'fills' | 'strokes'
+    ) => {
       for (const paint of paints) {
         if (paint.type !== 'SOLID' || !paint.visible || !paint.color || node.boundVariables[field])
           continue
@@ -31,6 +38,6 @@ export default defineRule({
       }
     }
     checkPaints(node.fills, 'fills')
-    checkPaints(node.strokes as typeof node.fills, 'strokes')
+    checkPaints(node.strokes, 'strokes')
   }
 })
diff --git a/packages/core/src/lint/types.ts b/packages/core/src/lint/types.ts
index e99512b29..2d3a2f5d6 100644
--- a/packages/core/src/lint/types.ts
+++ b/packages/core/src/lint/types.ts
@@ -78,6 +78,7 @@ export interface LintNode {
     visible: boolean
     radius: number
   }>
+  parent?: LintNode
 }
 
 export interface RuleContext {
diff --git a/packages/core/src/lint/utils.ts b/packages/core/src/lint/utils.ts
index 053e1c0d1..4be5a5b64 100644
--- a/packages/core/src/lint/utils.ts
+++ b/packages/core/src/lint/utils.ts
@@ -10,15 +10,17 @@ export function isMultipleOf(value: number, base: number, tolerance = 0.01): boo
   return remainder < tolerance || base - remainder < tolerance
 }
 
-export function getNodePath(node: {
+interface LintPathNode {
   name: string
-  parent?: { name: string; parent?: unknown }
-}): string[] {
+  parent?: LintPathNode
+}
+
+export function getNodePath(node: LintPathNode): string[] {
   const path: string[] = []
-  let current: typeof node | undefined = node
+  let current: LintPathNode | undefined = node
   while (current) {
     path.unshift(current.name)
-    current = current.parent as typeof node | undefined
+    current = current.parent
   }
   return path
 }
diff --git a/packages/vue/src/canvas/node-edit-input/bend.ts b/packages/vue/src/canvas/node-edit-input/bend.ts
index b42fc4c86..190f1b9ed 100644
--- a/packages/vue/src/canvas/node-edit-input/bend.ts
+++ b/packages/vue/src/canvas/node-edit-input/bend.ts
@@ -28,8 +28,7 @@ export type CanvasNodeEditMethods = Partial<{
 }>
 
 export function getCanvasNodeEditState(editor: Editor): CanvasNodeEditState | null | undefined {
-  return (editor.state as Editor['state'] & { nodeEditState?: CanvasNodeEditState | null })
-    .nodeEditState
+  return editor.state.nodeEditState as CanvasNodeEditState | null | undefined
 }
 
 export function resolveBendTargetHandle(
diff --git a/packages/vue/src/canvas/pen-input/use.ts b/packages/vue/src/canvas/pen-input/use.ts
index 644c109af..3d11900c7 100644
--- a/packages/vue/src/canvas/pen-input/use.ts
+++ b/packages/vue/src/canvas/pen-input/use.ts
@@ -7,8 +7,6 @@ import { createPenDrag, handlePenDragMove } from '#vue/canvas/pen-input/drag'
 import { handlePenNodeEditDown } from '#vue/shared/input/node-edit'
 import type { DragState } from '#vue/shared/input/types'
 
-type NodeEditState = NonNullable<Editor['state']> & { nodeEditState?: object | null }
-
 type SetDrag = (drag: DragState) => void
 
 export function startPenInput(
@@ -22,7 +20,7 @@ export function startPenInput(
   editor.state.penCursorX = null
   editor.state.penCursorY = null
 
-  const nodeEditState = (editor.state as NodeEditState).nodeEditState
+  const nodeEditState = editor.state.nodeEditState
   if (nodeEditState) {
     handlePenNodeEditDown(e, cx, cy, editor)
     return true
diff --git a/packages/vue/src/canvas/surface/gl-surface.ts b/packages/vue/src/canvas/surface/gl-surface.ts
index b878bdadf..904542f69 100644
--- a/packages/vue/src/canvas/surface/gl-surface.ts
+++ b/packages/vue/src/canvas/surface/gl-surface.ts
@@ -12,10 +12,9 @@ export function sizeCanvas(canvas: HTMLCanvasElement, editor: Editor) {
   const dpr = window.devicePixelRatio || 1
   canvas.width = canvas.clientWidth * dpr
   canvas.height = canvas.clientHeight * dpr
-  const maybeSizedEditor = editor as Editor & {
-    setViewportSize?: (width: number, height: number) => void
+  if ('setViewportSize' in editor && typeof editor.setViewportSize === 'function') {
+    editor.setViewportSize(canvas.clientWidth, canvas.clientHeight)
   }
-  maybeSizedEditor.setViewportSize?.(canvas.clientWidth, canvas.clientHeight)
 }
 
 export function makeGLSurface(
diff --git a/packages/vue/src/shared/input/node-edit/hit-test.ts b/packages/vue/src/shared/input/node-edit/hit-test.ts
index 416ee9732..2363f10ff 100644
--- a/packages/vue/src/shared/input/node-edit/hit-test.ts
+++ b/packages/vue/src/shared/input/node-edit/hit-test.ts
@@ -14,10 +14,7 @@ export type NodeEditState = {
 }
 
 export function getNodeEditState(editor: Editor): NodeEditState | null {
-  return (
-    (editor.state as Editor['state'] & { nodeEditState?: NodeEditState | null }).nodeEditState ??
-    null
-  )
+  return (editor.state.nodeEditState as NodeEditState | null) ?? null
 }
 
 export const NODE_HIT_THRESHOLD = 8
diff --git a/src/app/document/autosave/create.ts b/src/app/document/autosave/create.ts
index bcb422d07..9a43da051 100644
--- a/src/app/document/autosave/create.ts
+++ b/src/app/document/autosave/create.ts
@@ -1,5 +1,4 @@
-import { useDebounceFn } from '@vueuse/core'
-import { watch } from 'vue'
+import { watchDebounced } from '@vueuse/core'
 
 import type { EditorState } from '@open-pencil/core/editor'
 
@@ -18,29 +17,20 @@ export function createAutosave({
   hasWritableSource,
   saveCurrentDocument
 }: AutosaveOptions) {
-  const debouncedAutosave = useDebounceFn(async () => {
-    if (state.sceneVersion === getSavedVersion()) return
-    if (!state.autosaveEnabled) return
-    try {
-      await saveCurrentDocument()
-    } catch (e) {
-      console.warn('Autosave failed:', e)
-    }
-  }, 3000)
-
-  watch(
+  const stop = watchDebounced(
     () => state.sceneVersion,
-    (version) => {
+    async (version) => {
       if (version === getSavedVersion()) return
       if (!state.autosaveEnabled) return
       if (!hasWritableSource()) return
-      void debouncedAutosave()
-    }
+      try {
+        await saveCurrentDocument()
+      } catch (e) {
+        console.warn('Autosave failed:', e)
+      }
+    },
+    { debounce: 3000 }
   )
 
-  function disposeAutosave() {
-    ;(debouncedAutosave as typeof debouncedAutosave & { cancel?: () => void }).cancel?.()
-  }
-
-  return { disposeAutosave }
+  return { disposeAutosave: stop }
 }
diff --git a/src/app/editor/pen/resume.ts b/src/app/editor/pen/resume.ts
index 32dae20cc..6e15b93b3 100644
--- a/src/app/editor/pen/resume.ts
+++ b/src/app/editor/pen/resume.ts
@@ -1,15 +1,8 @@
 import type { EditorState } from '@open-pencil/core/editor'
-import type { Fill, SceneNode, VectorSegment, VectorVertex } from '@open-pencil/core/scene-graph'
+import type { SceneNode, VectorSegment, VectorVertex } from '@open-pencil/core/scene-graph'
 
-type ResumablePenState = NonNullable<EditorState['penState']> & {
-  resumingNodeId?: string
-  resumedFills?: Fill[]
-  resumedStrokes?: SceneNode['strokes']
-}
-
-export type PenState = Omit<EditorState, 'penState'> & {
-  penState: ResumablePenState | null
-}
+export type PenState = EditorState
+type PenStateInit = NonNullable<EditorState['penState']>
 
 export function absoluteVertices(node: SceneNode, vertices: VectorVertex[]): VectorVertex[] {
   return vertices.map((v) => ({
@@ -31,7 +24,7 @@ export function createResumedPenState(
   node: SceneNode,
   vertices: VectorVertex[],
   segments: VectorSegment[]
-): ResumablePenState {
+): PenStateInit {
   return {
     vertices,
     segments,
diff --git a/src/app/editor/session/types.ts b/src/app/editor/session/types.ts
index 75dce8cfd..956273f17 100644
--- a/src/app/editor/session/types.ts
+++ b/src/app/editor/session/types.ts
@@ -1,6 +1,4 @@
 import { createDefaultEditorState, type EditorState } from '@open-pencil/core/editor'
-import type { Fill, SceneNode, VectorSegment, VectorVertex } from '@open-pencil/core/scene-graph'
-import type { Vector } from '@open-pencil/core/types'
 
 import type { NodeEditState } from '@/app/editor/vector-edit/types'
 
@@ -23,18 +21,7 @@ export function createInitialAppEditorState(pageId: string): AppEditorState {
   }
 }
 
-export type AppEditorState = Omit<EditorState, 'penState'> & {
-  penState: {
-    vertices: VectorVertex[]
-    segments: VectorSegment[]
-    dragTangent: Vector | null
-    oppositeDragTangent: Vector | null
-    closingToFirst: boolean
-    pendingClose?: boolean
-    resumingNodeId?: string
-    resumedFills?: Fill[]
-    resumedStrokes?: SceneNode['strokes']
-  } | null
+export type AppEditorState = EditorState & {
   showUI: boolean
   showRulers: boolean
   showRemoteCursors: boolean