diff --git a/oxlint.json b/oxlint.json
index b911cb815..8847f4171 100644
--- a/oxlint.json
+++ b/oxlint.json
@@ -19,13 +19,19 @@
       }]
     }],
 
+    "no-empty-function": "error",
+
     "typescript/no-explicit-any": "warn",
     "typescript/no-non-null-assertion": "warn",
     "typescript/no-floating-promises": "error",
     "typescript/no-misused-promises": "error",
     "typescript/consistent-type-imports": "error",
+    "typescript/consistent-return": "error",
+    "typescript/no-unnecessary-condition": "error",
     "typescript/no-unnecessary-type-assertion": "error",
+    "typescript/no-unnecessary-type-parameters": "error",
     "typescript/prefer-optional-chain": "error",
+    "typescript/prefer-for-of": "error",
 
     "import/no-cycle": "error",
     "import/no-self-import": "error",
@@ -34,6 +40,8 @@
 
     "unicorn/no-instanceof-array": "error",
     "unicorn/no-typeof-undefined": "error",
+    "unicorn/no-nested-ternary": "error",
+    "unicorn/consistent-existence-index-check": "error",
 
     "vue/no-arrow-functions-in-watch": "error",
     "vue/no-deprecated-destroyed-lifecycle": "error",
diff --git a/src/automation/bridge.ts b/src/automation/bridge.ts
index eae491de6..d9ee2301a 100644
--- a/src/automation/bridge.ts
+++ b/src/automation/bridge.ts
@@ -156,7 +156,7 @@ export function startAutomationBridge(server: ViteServer) {
     if (provided !== authToken) {
       return c.json({ error: 'Unauthorized' }, 401)
     }
-    await next()
+    return next()
   })
 
   app.post('/rpc', async (c) => {
diff --git a/src/automation/server.ts b/src/automation/server.ts
index e3dc042b8..00932d422 100644
--- a/src/automation/server.ts
+++ b/src/automation/server.ts
@@ -39,10 +39,10 @@ export function connectAutomation(getStore: () => EditorStore) {
     const store = getStore()
 
     if (command === 'eval') {
-      const code = (args as { code?: string })?.code
+      const code = (args as { code?: string }).code
       if (!code) throw new Error('Missing "code" in args')
       const figma = makeFigma()
-      const AsyncFunction = Object.getPrototypeOf(async function () {}).constructor
+      const AsyncFunction = Object.getPrototypeOf(async function () { /* noop */ }).constructor
       const wrappedCode = code.trim().startsWith('return')
         ? code
         : `return (async () => { ${code} })()`
@@ -53,14 +53,14 @@ export function connectAutomation(getStore: () => EditorStore) {
     }
 
     if (command === 'tool') {
-      const toolName = (args as { name?: string })?.name
-      const toolArgs = (args as { args?: Record<string, unknown> })?.args ?? {}
+      const toolName = (args as { name?: string }).name
+      const toolArgs = (args as { args?: Record<string, unknown> }).args ?? {}
       if (!toolName) throw new Error('Missing "name" in args')
 
       if (toolName === 'render' && toolArgs.tree) {
         const tree = toolArgs.tree as Parameters<typeof renderTreeNode>[1]
         const result = renderTreeNode(store.graph, tree, {
-          parentId: (toolArgs.parent_id as string) ?? store.state.currentPageId,
+          parentId: (toolArgs.parent_id as string | undefined) ?? store.state.currentPageId,
           x: toolArgs.x as number | undefined,
           y: toolArgs.y as number | undefined
         })
@@ -96,7 +96,7 @@ export function connectAutomation(getStore: () => EditorStore) {
       )
       if (!data) throw new Error('Export failed')
       let binary = ''
-      for (let i = 0; i < data.length; i++) binary += String.fromCharCode(data[i])
+      for (const byte of data) binary += String.fromCharCode(byte)
       const base64 = btoa(binary)
       return {
         ok: true,
@@ -113,7 +113,7 @@ export function connectAutomation(getStore: () => EditorStore) {
         nodeIds.length === 1
           ? sceneNodeToJSX(nodeIds[0], store.graph, style)
           : selectionToJSX(nodeIds, store.graph, style)
-      return { ok: true, result: { jsx: jsx ?? '' } }
+      return { ok: true, result: { jsx } }
     }
 
     const result = executeRpcCommand(store.graph, command, args ?? {})
diff --git a/src/components/ChatPanel.vue b/src/components/ChatPanel.vue
index e238cad12..eead37d45 100644
--- a/src/components/ChatPanel.vue
+++ b/src/components/ChatPanel.vue
@@ -31,7 +31,7 @@ function handleSubmit(text: string) {
     const c = ensureChat()
     if (c) chat.value = markRaw(c)
   }
-  chat.value?.sendMessage({ text }).catch(() => {})
+  chat.value?.sendMessage({ text }).catch(() => { /* user-facing error handled by UI */ })
 }
 
 function handleStop() {
diff --git a/src/components/LayerTree.vue b/src/components/LayerTree.vue
index d2fd7b4bc..8535adb91 100644
--- a/src/components/LayerTree.vue
+++ b/src/components/LayerTree.vue
@@ -117,7 +117,7 @@ function onLayerRightClick(e: MouseEvent) {
 
 function toggleExpand(id: string) {
   const idx = expanded.value.indexOf(id)
-  if (idx >= 0) {
+  if (idx !== -1) {
     expanded.value = expanded.value.filter((e) => e !== id)
   } else {
     expanded.value = [...expanded.value, id]
diff --git a/src/components/VariablesDialog.vue b/src/components/VariablesDialog.vue
index 2624de3f8..23c4d3fb5 100644
--- a/src/components/VariablesDialog.vue
+++ b/src/components/VariablesDialog.vue
@@ -1,5 +1,5 @@
 <script setup lang="ts">
-import { ref, computed, watch, nextTick, h } from 'vue'
+import { ref, computed, watch, nextTick, h, type Component } from 'vue'
 import {
   DialogRoot,
   DialogPortal,
@@ -273,14 +273,13 @@ const columns = computed<ColumnDef<Variable>[]>(() => {
     cell: ({ row }) => {
       const v = row.original
       const iconClass = 'size-3.5 shrink-0 text-muted'
-      const iconComponent =
-        v.type === 'COLOR'
-          ? IconPalette
-          : v.type === 'FLOAT'
-            ? IconHash
-            : v.type === 'STRING'
-              ? IconType
-              : IconToggleLeft
+      const VARIABLE_TYPE_ICONS: Record<string, Component> = {
+        COLOR: IconPalette,
+        FLOAT: IconHash,
+        STRING: IconType,
+        BOOLEAN: IconToggleLeft
+      }
+      const iconComponent = VARIABLE_TYPE_ICONS[v.type] ?? IconToggleLeft
       const icon = h(iconComponent, { class: iconClass })
 
       return h('div', { class: 'flex items-center gap-2' }, [
diff --git a/src/components/properties/AppearanceSection.vue b/src/components/properties/AppearanceSection.vue
index 01deb4b3d..f89603b6a 100644
--- a/src/components/properties/AppearanceSection.vue
+++ b/src/components/properties/AppearanceSection.vue
@@ -27,7 +27,7 @@ const hasCornerRadius = computed(() => {
 
 const visibilityState = computed(() => {
   const v = merged('visible')
-  return v === MIXED ? 'mixed' : v ? 'visible' : 'hidden'
+  return v === MIXED ? 'mixed' : (v ? 'visible' : 'hidden')
 })
 
 function toggleVisibility() {
diff --git a/src/composables/use-canvas-input.ts b/src/composables/use-canvas-input.ts
index a39ecc20a..9d4156466 100644
--- a/src/composables/use-canvas-input.ts
+++ b/src/composables/use-canvas-input.ts
@@ -494,7 +494,7 @@ export function useCanvasInput(
 
       // Check proximity to first vertex for closing
       const first = store.state.penState.vertices[0]
-      if (store.state.penState.vertices.length > 2 && first) {
+      if (store.state.penState.vertices.length > 2) {
         const dist = Math.hypot(cx - first.x, cy - first.y)
         store.penSetClosingToFirst(dist < PEN_CLOSE_THRESHOLD)
       }
@@ -746,26 +746,24 @@ export function useCanvasInput(
       return
     }
 
-    if (d.type === 'marquee') {
-      const minX = Math.min(d.startX, cx)
-      const minY = Math.min(d.startY, cy)
-      const maxX = Math.max(d.startX, cx)
-      const maxY = Math.max(d.startY, cy)
+    const minX = Math.min(d.startX, cx)
+    const minY = Math.min(d.startY, cy)
+    const maxX = Math.max(d.startX, cx)
+    const maxY = Math.max(d.startY, cy)
 
-      const hits: string[] = []
-      for (const node of store.graph.getChildren(store.state.currentPageId)) {
-        if (
-          node.x + node.width > minX &&
-          node.x < maxX &&
-          node.y + node.height > minY &&
-          node.y < maxY
-        ) {
-          hits.push(node.id)
-        }
+    const hits: string[] = []
+    for (const node of store.graph.getChildren(store.state.currentPageId)) {
+      if (
+        node.x + node.width > minX &&
+        node.x < maxX &&
+        node.y + node.height > minY &&
+        node.y < maxY
+      ) {
+        hits.push(node.id)
       }
-      store.select(hits)
-      store.setMarquee({ x: minX, y: minY, width: maxX - minX, height: maxY - minY })
     }
+    store.select(hits)
+    store.setMarquee({ x: minX, y: minY, width: maxX - minX, height: maxY - minY })
   }
 
   function applyResize(d: DragResize, cx: number, cy: number, constrain: boolean) {
@@ -1067,9 +1065,9 @@ export function useCanvasInput(
     const allChildren = store.graph.getChildren(parent.id)
     let realIndex = 0
     let filteredCount = 0
-    for (let i = 0; i < allChildren.length; i++) {
-      if (store.state.selectedIds.has(allChildren[i].id)) continue
-      if (allChildren[i].layoutPositioning === 'ABSOLUTE') {
+    for (const child of allChildren) {
+      if (store.state.selectedIds.has(child.id)) continue
+      if (child.layoutPositioning === 'ABSOLUTE') {
         realIndex++
         continue
       }
@@ -1272,8 +1270,8 @@ export function useCanvasInput(
       const rect = canvas.getBoundingClientRect()
       pendingGesture = {
         scale: ge.scale,
-        sx: (ge.clientX ?? rect.width / 2) - rect.left,
-        sy: (ge.clientY ?? rect.height / 2) - rect.top
+        sx: ge.clientX - rect.left,
+        sy: ge.clientY - rect.top
       }
       if (!gestureRafId) {
         gestureRafId = requestAnimationFrame(flushGesture)
diff --git a/src/composables/use-canvas.ts b/src/composables/use-canvas.ts
index 0765cdba9..c6f3cb706 100644
--- a/src/composables/use-canvas.ts
+++ b/src/composables/use-canvas.ts
@@ -31,6 +31,7 @@ async function initWebGPU(ck: CanvasKit): Promise<WebGPUContext | null> {
   const adapter = await navigator.gpu.requestAdapter()
   if (!adapter) return null
   const device = await adapter.requestDevice()
+  // oxlint-disable-next-line typescript/no-unnecessary-condition -- WebGPU CanvasKit API may not exist at runtime
   const deviceContext = asWebGPU(ck).MakeGPUDeviceContext?.(device)
   if (!deviceContext) return null
   return { device, deviceContext }
@@ -51,6 +52,7 @@ export function useCanvas(canvasRef: Ref<HTMLCanvasElement | null>, store: Edito
     if (!canvas || destroyed) return
 
     ck = await getCanvasKit()
+    // oxlint-disable-next-line typescript/no-unnecessary-condition -- async race: destroyed may change during await
     if (destroyed) return
 
     if (getGpuBackend() === 'webgpu') {
diff --git a/src/composables/use-chat.ts b/src/composables/use-chat.ts
index d20e9c5b4..ab35eab73 100644
--- a/src/composables/use-chat.ts
+++ b/src/composables/use-chat.ts
@@ -126,6 +126,10 @@ function createModel(): LanguageModel {
       })
       return custom(effectiveModelID)
     }
+    default: {
+      const _exhaustive: never = providerID.value
+      throw new Error(`Unknown provider: ${String(_exhaustive)}`)
+    }
   }
 }
 
diff --git a/src/composables/use-menu.ts b/src/composables/use-menu.ts
index f61572b36..d3a199e37 100644
--- a/src/composables/use-menu.ts
+++ b/src/composables/use-menu.ts
@@ -49,7 +49,7 @@ export async function openFileDialog() {
 
 const store = useEditorStore()
 
-const MENU_ACTIONS: Record<string, () => void> = {
+const MENU_ACTIONS: Partial<Record<string, () => void>> = {
   new: () => createTab(),
   open: () => void openFileDialog(),
   close: () => {
diff --git a/src/composables/use-multi-props.ts b/src/composables/use-multi-props.ts
index eed05f6c8..1f72f33dc 100644
--- a/src/composables/use-multi-props.ts
+++ b/src/composables/use-multi-props.ts
@@ -13,7 +13,7 @@ export function useMultiProps() {
   const nodes = computed(() => store.selectedNodes.value)
   const isMulti = computed(() => nodes.value.length > 1)
   const active = computed(() => node.value || isMulti.value)
-  const activeNode = computed(() => node.value ?? nodes.value[0] ?? null)
+  const activeNode = computed(() => node.value ?? (nodes.value[0] as SceneNode | undefined) ?? null)
 
   function merged<K extends keyof SceneNode>(key: K): MixedValue<SceneNode[K]> {
     const all = nodes.value
@@ -36,7 +36,7 @@ export function useMultiProps() {
     store.requestRender()
   }
 
-  function isArrayMixed<K extends keyof SceneNode>(key: K): boolean {
+  function isArrayMixed(key: keyof SceneNode): boolean {
     const all = nodes.value
     if (all.length <= 1) return false
     const first = JSON.stringify(all[0][key])
diff --git a/src/stores/editor.ts b/src/stores/editor.ts
index 29cff242c..4879f9649 100644
--- a/src/stores/editor.ts
+++ b/src/stores/editor.ts
@@ -85,7 +85,7 @@ export const TOOLS: ToolDef[] = [
   { key: 'HAND', label: 'Hand', shortcut: 'H' }
 ]
 
-export const TOOL_SHORTCUTS: Record<string, Tool> = {
+export const TOOL_SHORTCUTS: Partial<Record<string, Tool>> = {
   v: 'SELECT',
   f: 'FRAME',
   s: 'SECTION',
@@ -612,13 +612,14 @@ export function createEditorStore() {
       state.documentName = file.name.replace(/\.fig$/i, '')
       downloadName = file.name
       state.selectedIds = new Set()
-      const firstPage = graph.getPages()[0]
-      state.currentPageId = firstPage?.id ?? graph.rootId
+      const firstPage = graph.getPages()[0] as SceneNode | undefined
+      const pageId = firstPage?.id ?? graph.rootId
+      state.currentPageId = pageId
       state.panX = 0
       state.panY = 0
       state.zoom = 1
       state.pageColor = { ...CANVAS_BG_COLOR }
-      await loadFontsForNodes(graph.getChildren(firstPage?.id ?? graph.rootId).map((n) => n.id))
+      await loadFontsForNodes(graph.getChildren(pageId).map((n) => n.id))
       requestRender()
       void startWatchingFile()
     } catch (e) {
@@ -1091,7 +1092,7 @@ export function createEditorStore() {
     const parentAbs = isTopLevel(parentId) ? { x: 0, y: 0 } : graph.getAbsolutePosition(parentId)
 
     const direction: LayoutMode =
-      nodes.length <= 1 ? 'VERTICAL' : maxX - minX >= maxY - minY ? 'HORIZONTAL' : 'VERTICAL'
+      nodes.length <= 1 ? 'VERTICAL' : (maxX - minX >= maxY - minY ? 'HORIZONTAL' : 'VERTICAL')
 
     const frame = graph.createNode('FRAME', parentId, {
       name: 'Frame',
@@ -2085,8 +2086,8 @@ export function createEditorStore() {
     const w = maxX - minX + padding * 2
     const h = maxY - minY + padding * 2
 
-    const viewW = window.innerWidth ?? 800
-    const viewH = window.innerHeight ?? 600
+    const viewW = window.innerWidth
+    const viewH = window.innerHeight
     const zoom = Math.min(viewW / w, viewH / h, 1)
 
     state.zoom = zoom
@@ -2114,8 +2115,8 @@ export function createEditorStore() {
   }
 
   function zoomTo100() {
-    const viewW = window.innerWidth ?? 800
-    const viewH = window.innerHeight ?? 600
+    const viewW = window.innerWidth
+    const viewH = window.innerHeight
     const centerX = (-state.panX + viewW / 2) / state.zoom
     const centerY = (-state.panY + viewH / 2) / state.zoom
 
diff --git a/src/stores/tabs.ts b/src/stores/tabs.ts
index 75519a174..0cde76f26 100644
--- a/src/stores/tabs.ts
+++ b/src/stores/tabs.ts
@@ -56,7 +56,7 @@ export function switchTab(tabId: string) {
 
 export function closeTab(tabId: string) {
   const idx = tabsRef.value.findIndex((t) => t.id === tabId)
-  if (idx < 0) return
+  if (idx === -1) return
 
   const wasActive = activeTabId.value === tabId
   tabsRef.value = tabsRef.value.filter((t) => t.id !== tabId)