diff --git a/packages/app/src/cli/services/dev/processes/theme-app-extension.test.ts b/packages/app/src/cli/services/dev/processes/theme-app-extension.test.ts
index bf9e0d15b01..fad6a5dc1c2 100644
--- a/packages/app/src/cli/services/dev/processes/theme-app-extension.test.ts
+++ b/packages/app/src/cli/services/dev/processes/theme-app-extension.test.ts
@@ -22,18 +22,9 @@ vi.mock('@shopify/cli-kit/node/themes/api')
 vi.mock('@shopify/cli-kit/node/context/fqdn')
 vi.mock('@shopify/cli-kit/node/ui', async (realImport) => {
   const realModule = await realImport<typeof import('@shopify/cli-kit/node/ui')>()
+  const mockModule = {renderInfo: vi.fn()}
 
-  return {
-    ...realModule,
-    renderInfo: vi.fn(),
-    renderTasks: vi.fn(async (tasks: any[]) => {
-      for (const task of tasks) {
-        // eslint-disable-next-line no-await-in-loop
-        await task.task({}, task)
-      }
-      return {}
-    }),
-  }
+  return {...realModule, ...mockModule}
 })
 
 describe('setupPreviewThemeAppExtensionsProcess', () => {
diff --git a/packages/cli-kit/src/private/node/testing/ui.ts b/packages/cli-kit/src/private/node/testing/ui.ts
index 76f31f36b69..58b8a7df29c 100644
--- a/packages/cli-kit/src/private/node/testing/ui.ts
+++ b/packages/cli-kit/src/private/node/testing/ui.ts
@@ -1,5 +1,5 @@
-import {Stdout, InkLifecycleRoot} from '../ui.js'
-import React, {ReactElement} from 'react'
+import {Stdout} from '../ui.js'
+import {ReactElement} from 'react'
 import {render as inkRender} from 'ink'
 
 import {EventEmitter} from 'events'
@@ -66,7 +66,7 @@ export const render = (tree: ReactElement, options: RenderOptions = {}): Instanc
   const stderr = new Stderr()
   const stdin = new Stdin()
 
-  const instance = inkRender(React.createElement(InkLifecycleRoot, null, tree), {
+  const instance = inkRender(tree, {
     stdout: options.stdout ?? (stdout as any),
 
     stderr: options.stderr ?? (stderr as any),
@@ -78,7 +78,7 @@ export const render = (tree: ReactElement, options: RenderOptions = {}): Instanc
   })
 
   return {
-    rerender: (tree: ReactElement) => instance.rerender(React.createElement(InkLifecycleRoot, null, tree)),
+    rerender: instance.rerender,
     unmount: instance.unmount,
     cleanup: instance.cleanup,
     waitUntilExit: () => trackPromise(instance.waitUntilExit().then(() => {})),
diff --git a/packages/cli-kit/src/private/node/ui.tsx b/packages/cli-kit/src/private/node/ui.tsx
index d7cc567d0aa..06a91c7ba45 100644
--- a/packages/cli-kit/src/private/node/ui.tsx
+++ b/packages/cli-kit/src/private/node/ui.tsx
@@ -3,49 +3,11 @@ import {Logger, LogLevel} from '../../public/node/output.js'
 import {isUnitTest} from '../../public/node/context/local.js'
 import {treeKill} from '../../public/node/tree-kill.js'
 
-import React, {ReactElement, createContext, useCallback, useContext, useEffect, useState} from 'react'
-import {Key, render as inkRender, RenderOptions, useApp} from 'ink'
+import {ReactElement} from 'react'
+import {Key, render as inkRender, RenderOptions} from 'ink'
 
 import {EventEmitter} from 'events'
 
-const CompletionContext = createContext<((error?: Error) => void) | null>(null)
-
-/**
- * Signal that the current Ink tree is done. Must be called within an
- * InkLifecycleRoot — throws if the provider is missing so lifecycle
- * bugs surface immediately instead of silently hanging.
- */
-export function useComplete(): (error?: Error) => void {
-  const complete = useContext(CompletionContext)
-  if (!complete) {
-    throw new Error('useComplete() called outside InkLifecycleRoot')
-  }
-  return complete
-}
-
-/**
- * Root wrapper for Ink trees. Owns the single `exit()` call site — children
- * signal completion via `useComplete()`, which sets state here. The `useEffect`
- * fires post-render, guaranteeing all batched state updates have been flushed
- * before the tree is torn down.
- */
-export function InkLifecycleRoot({children}: {children: React.ReactNode}) {
-  const {exit} = useApp()
-  const [exitResult, setExitResult] = useState<{error?: Error} | null>(null)
-
-  const complete = useCallback((error?: Error) => {
-    setExitResult({error})
-  }, [])
-
-  useEffect(() => {
-    if (exitResult !== null) {
-      exit(exitResult.error)
-    }
-  }, [exitResult, exit])
-
-  return <CompletionContext.Provider value={complete}>{children}</CompletionContext.Provider>
-}
-
 interface RenderOnceOptions {
   logLevel?: LogLevel
   logger?: Logger
@@ -65,8 +27,10 @@ export function renderOnce(element: JSX.Element, {logLevel = 'info', renderOptio
 }
 
 export async function render(element: JSX.Element, options?: RenderOptions) {
-  const {waitUntilExit} = inkRender(<InkLifecycleRoot>{element}</InkLifecycleRoot>, options)
+  const {waitUntilExit} = inkRender(element, options)
   await waitUntilExit()
+  // We need to wait for other pending tasks -- unmounting of the ink component -- to complete
+  return new Promise((resolve) => setImmediate(resolve))
 }
 
 interface Instance {
diff --git a/packages/cli-kit/src/private/node/ui/components/AutocompletePrompt.tsx b/packages/cli-kit/src/private/node/ui/components/AutocompletePrompt.tsx
index 01f277dfe66..80bf98d3ed2 100644
--- a/packages/cli-kit/src/private/node/ui/components/AutocompletePrompt.tsx
+++ b/packages/cli-kit/src/private/node/ui/components/AutocompletePrompt.tsx
@@ -5,11 +5,10 @@ import {InfoMessageProps} from './Prompts/InfoMessage.js'
 import {Message, PromptLayout} from './Prompts/PromptLayout.js'
 import {throttle} from '../../../../public/common/function.js'
 import {AbortSignal} from '../../../../public/node/abort.js'
-import {useComplete} from '../../ui.js'
 import usePrompt, {PromptState} from '../hooks/use-prompt.js'
 
 import React, {ReactElement, useCallback, useEffect, useRef, useState} from 'react'
-import {Box} from 'ink'
+import {Box, useApp} from 'ink'
 
 export interface SearchResults<T> {
   data: SelectItem<T>[]
@@ -43,7 +42,7 @@ function AutocompletePrompt<T>({
   infoMessage,
   groupOrder,
 }: React.PropsWithChildren<AutocompletePromptProps<T>>): ReactElement | null {
-  const complete = useComplete()
+  const {exit: unmountInk} = useApp()
   const [searchTerm, setSearchTerm] = useState('')
   const [searchResults, setSearchResults] = useState<SelectItem<T>[]>(choices)
   const canSearch = choices.length > MIN_NUMBER_OF_ITEMS_FOR_SEARCH
@@ -73,10 +72,10 @@ function AutocompletePrompt<T>({
   useEffect(() => {
     if (promptState === PromptState.Submitted && answer) {
       setSearchTerm('')
+      unmountInk()
       onSubmit(answer.value)
-      complete()
     }
-  }, [answer, onSubmit, promptState, complete])
+  }, [answer, onSubmit, promptState, unmountInk])
 
   const setLoadingWhenSlow = useRef<NodeJS.Timeout>()
 
diff --git a/packages/cli-kit/src/private/node/ui/components/ConcurrentOutput.test.tsx b/packages/cli-kit/src/private/node/ui/components/ConcurrentOutput.test.tsx
index d0978a81a0b..f9d61c55556 100644
--- a/packages/cli-kit/src/private/node/ui/components/ConcurrentOutput.test.tsx
+++ b/packages/cli-kit/src/private/node/ui/components/ConcurrentOutput.test.tsx
@@ -28,7 +28,6 @@ describe('ConcurrentOutput', () => {
     // Given
     const backendSync = new Synchronizer()
     const frontendSync = new Synchronizer()
-    const gate = new Synchronizer()
 
     const backendProcess = {
       prefix: 'backend',
@@ -38,7 +37,6 @@ describe('ConcurrentOutput', () => {
         stdout.write('third backend message')
 
         backendSync.resolve()
-        await gate.promise
       },
     }
 
@@ -52,7 +50,6 @@ describe('ConcurrentOutput', () => {
         stdout.write('third frontend message')
 
         frontendSync.resolve()
-        await gate.promise
       },
     }
     // When
@@ -75,8 +72,6 @@ describe('ConcurrentOutput', () => {
       00:00:00 │ frontend │ third frontend message
       "
     `)
-
-    gate.resolve()
   })
 
   test('strips ansi codes from the output by default', async () => {
@@ -84,14 +79,12 @@ describe('ConcurrentOutput', () => {
 
     // Given
     const processSync = new Synchronizer()
-    const gate = new Synchronizer()
     const processes = [
       {
         prefix: '1',
         action: async (stdout: Writable, _stderr: Writable, _signal: AbortSignal) => {
           stdout.write(`\u001b[32m${output}\u001b[39m`)
           processSync.resolve()
-          await gate.promise
         },
       },
     ]
@@ -105,7 +98,6 @@ describe('ConcurrentOutput', () => {
     const logColumns = renderInstance.lastFrame()!.split('│')
     expect(logColumns.length).toBe(3)
     expect(logColumns[2]?.trim()).toEqual(output)
-    gate.resolve()
   })
 
   test('does not strip ansi codes from the output when stripAnsi is false', async () => {
@@ -113,7 +105,6 @@ describe('ConcurrentOutput', () => {
 
     // Given
     const processSync = new Synchronizer()
-    const gate = new Synchronizer()
     const processes = [
       {
         prefix: '1',
@@ -122,7 +113,6 @@ describe('ConcurrentOutput', () => {
             stdout.write(output)
           })
           processSync.resolve()
-          await gate.promise
         },
       },
     ]
@@ -136,13 +126,11 @@ describe('ConcurrentOutput', () => {
     const logColumns = renderInstance.lastFrame()!.split('│')
     expect(logColumns.length).toBe(3)
     expect(logColumns[2]?.trim()).toEqual(output)
-    gate.resolve()
   })
 
   test('renders custom prefixes on log lines', async () => {
     // Given
     const processSync = new Synchronizer()
-    const gate = new Synchronizer()
     const extensionName = 'my-extension'
     const processes = [
       {
@@ -152,7 +140,6 @@ describe('ConcurrentOutput', () => {
             stdout.write('foo bar')
           })
           processSync.resolve()
-          await gate.promise
         },
       },
     ]
@@ -174,14 +161,12 @@ describe('ConcurrentOutput', () => {
     const logColumns = unstyled(renderInstance.lastFrame()!).split('│')
     expect(logColumns.length).toBe(3)
     expect(logColumns[1]?.trim()).toEqual(extensionName)
-    gate.resolve()
   })
 
   test('renders prefix column width based on prefixColumnSize', async () => {
     // Given
     const processSync1 = new Synchronizer()
     const processSync2 = new Synchronizer()
-    const gate = new Synchronizer()
 
     const columnSize = 5
     const processes = [
@@ -190,7 +175,6 @@ describe('ConcurrentOutput', () => {
         action: async (stdout: Writable, _stderr: Writable, _signal: AbortSignal) => {
           stdout.write('foo')
           processSync1.resolve()
-          await gate.promise
         },
       },
       {
@@ -198,7 +182,6 @@ describe('ConcurrentOutput', () => {
         action: async (stdout: Writable, _stderr: Writable, _signal: AbortSignal) => {
           stdout.write('bar')
           processSync2.resolve()
-          await gate.promise
         },
       },
     ]
@@ -223,25 +206,22 @@ describe('ConcurrentOutput', () => {
       // Including spacing
       expect(logColumns[1]?.length).toBe(columnSize + 2)
     })
-    gate.resolve()
   })
 
   test('renders prefix column width based on processes by default', async () => {
     // Given
     const processSync = new Synchronizer()
-    const gate = new Synchronizer()
     const processes = [
       {
         prefix: '1',
         action: async (stdout: Writable, _stderr: Writable, _signal: AbortSignal) => {
           stdout.write('foo')
           processSync.resolve()
-          await gate.promise
         },
       },
-      {prefix: '12', action: async () => gate.promise},
-      {prefix: '123', action: async () => gate.promise},
-      {prefix: '1234', action: async () => gate.promise},
+      {prefix: '12', action: async () => {}},
+      {prefix: '123', action: async () => {}},
+      {prefix: '1234', action: async () => {}},
     ]
 
     // When
@@ -254,23 +234,20 @@ describe('ConcurrentOutput', () => {
     expect(logColumns.length).toBe(3)
     // 4 is largest prefix, plus spacing
     expect(logColumns[1]?.length).toBe(4 + 2)
-    gate.resolve()
   })
 
   test('does not render prefix column larger than max', async () => {
     // Given
     const processSync = new Synchronizer()
-    const gate = new Synchronizer()
     const processes = [
       {
         prefix: '1',
         action: async (stdout: Writable, _stderr: Writable, _signal: AbortSignal) => {
           stdout.write('foo')
           processSync.resolve()
-          await gate.promise
         },
       },
-      {prefix: new Array(26).join('0'), action: async () => gate.promise},
+      {prefix: new Array(26).join('0'), action: async () => {}},
     ]
 
     // When
@@ -283,7 +260,6 @@ describe('ConcurrentOutput', () => {
     expect(logColumns.length).toBe(3)
     // 25 is largest column allowed, plus spacing
     expect(logColumns[1]?.length).toBe(25 + 2)
-    gate.resolve()
   })
 
   test('rejects with the error thrown inside one of the processes', async () => {
diff --git a/packages/cli-kit/src/private/node/ui/components/ConcurrentOutput.tsx b/packages/cli-kit/src/private/node/ui/components/ConcurrentOutput.tsx
index b866189e5ae..e447b8814a6 100644
--- a/packages/cli-kit/src/private/node/ui/components/ConcurrentOutput.tsx
+++ b/packages/cli-kit/src/private/node/ui/components/ConcurrentOutput.tsx
@@ -1,8 +1,7 @@
 import {OutputProcess} from '../../../../public/node/output.js'
 import {AbortSignal} from '../../../../public/node/abort.js'
-import {useComplete} from '../../ui.js'
 import React, {FunctionComponent, useCallback, useEffect, useMemo, useState} from 'react'
-import {Box, Static, Text, TextProps} from 'ink'
+import {Box, Static, Text, TextProps, useApp} from 'ink'
 import figures from 'figures'
 import stripAnsi from 'strip-ansi'
 
@@ -93,8 +92,7 @@ const ConcurrentOutput: FunctionComponent<ConcurrentOutputProps> = ({
   useAlternativeColorPalette = false,
 }) => {
   const [processOutput, setProcessOutput] = useState<Chunk[]>([])
-  const [completionResult, setCompletionResult] = useState<{error?: Error} | null>(null)
-  const complete = useComplete()
+  const {exit: unmountInk} = useApp()
   const concurrentColors: TextProps['color'][] = useMemo(
     () =>
       useAlternativeColorPalette
@@ -181,25 +179,24 @@ const ConcurrentOutput: FunctionComponent<ConcurrentOutputProps> = ({
           }),
         )
         if (!keepRunningAfterProcessesResolve) {
-          setCompletionResult({})
+          // Defer unmount so React 19 can flush batched setProcessOutput
+          // state updates before the component tree is torn down.
+          // Use setImmediate → setTimeout(0) to span two event-loop phases,
+          // giving React's scheduler (which uses setImmediate in Node.js)
+          // a full cycle to flush before we tear down the component tree.
+          setImmediate(() => setTimeout(() => unmountInk(), 0))
         }
         // eslint-disable-next-line no-catch-all/no-catch-all
       } catch (error: unknown) {
         if (!keepRunningAfterProcessesResolve) {
-          setCompletionResult({error: error as Error})
+          setImmediate(() => setTimeout(() => unmountInk(error as Error | undefined), 0))
         }
       }
     }
 
     // eslint-disable-next-line @typescript-eslint/no-floating-promises
     runProcesses()
-  }, [abortSignal, processes, writableStream, keepRunningAfterProcessesResolve])
-
-  useEffect(() => {
-    if (completionResult !== null) {
-      complete(completionResult.error)
-    }
-  }, [completionResult, complete])
+  }, [abortSignal, processes, writableStream, unmountInk, keepRunningAfterProcessesResolve])
 
   const {lineVertical} = figures
 
diff --git a/packages/cli-kit/src/private/node/ui/components/DangerousConfirmationPrompt.tsx b/packages/cli-kit/src/private/node/ui/components/DangerousConfirmationPrompt.tsx
index 533b20ac8c3..d877dd98440 100644
--- a/packages/cli-kit/src/private/node/ui/components/DangerousConfirmationPrompt.tsx
+++ b/packages/cli-kit/src/private/node/ui/components/DangerousConfirmationPrompt.tsx
@@ -1,7 +1,7 @@
 import {TextInput} from './TextInput.js'
 import {InlineToken, TokenItem, TokenizedText} from './TokenizedText.js'
 import {InfoTable, InfoTableProps} from './Prompts/InfoTable.js'
-import {handleCtrlC, useComplete} from '../../ui.js'
+import {handleCtrlC} from '../../ui.js'
 import useLayout from '../hooks/use-layout.js'
 import {messageWithPunctuation} from '../utilities.js'
 import {AbortSignal} from '../../../../public/node/abort.js'
@@ -9,7 +9,7 @@ import useAbortSignal from '../hooks/use-abort-signal.js'
 import usePrompt, {PromptState} from '../hooks/use-prompt.js'
 
 import React, {FunctionComponent, useCallback, useEffect, useState} from 'react'
-import {Box, useInput, Text} from 'ink'
+import {Box, useApp, useInput, Text} from 'ink'
 import figures from 'figures'
 
 export interface DangerousConfirmationPromptProps {
@@ -38,7 +38,7 @@ const DangerousConfirmationPrompt: FunctionComponent<DangerousConfirmationPrompt
   const {promptState, setPromptState, answer, setAnswer} = usePrompt<string>({
     initialAnswer: '',
   })
-  const complete = useComplete()
+  const {exit: unmountInk} = useApp()
   const [error, setError] = useState<TokenItem<InlineToken> | undefined>(undefined)
   const color = promptState === PromptState.Error ? 'red' : 'cyan'
   const underline = new Array(oneThird - 3).fill('▔')
@@ -67,12 +67,12 @@ const DangerousConfirmationPrompt: FunctionComponent<DangerousConfirmationPrompt
   useEffect(() => {
     if (promptState === PromptState.Submitted) {
       onSubmit(true)
-      complete()
+      unmountInk()
     } else if (promptState === PromptState.Cancelled) {
       onSubmit(false)
-      complete()
+      unmountInk()
     }
-  }, [onSubmit, promptState, complete])
+  }, [onSubmit, promptState, unmountInk])
 
   const completed = promptState === PromptState.Submitted || promptState === PromptState.Cancelled
 
diff --git a/packages/cli-kit/src/private/node/ui/components/SelectPrompt.tsx b/packages/cli-kit/src/private/node/ui/components/SelectPrompt.tsx
index 0794bf447c5..8e1606efb37 100644
--- a/packages/cli-kit/src/private/node/ui/components/SelectPrompt.tsx
+++ b/packages/cli-kit/src/private/node/ui/components/SelectPrompt.tsx
@@ -3,10 +3,10 @@ import {InfoTableProps} from './Prompts/InfoTable.js'
 import {InfoMessageProps} from './Prompts/InfoMessage.js'
 import {Message, PromptLayout} from './Prompts/PromptLayout.js'
 import {AbortSignal} from '../../../../public/node/abort.js'
-import {useComplete} from '../../ui.js'
 import usePrompt, {PromptState} from '../hooks/use-prompt.js'
 
 import React, {ReactElement, useCallback, useEffect} from 'react'
+import {useApp} from 'ink'
 
 export interface SelectPromptProps<T> {
   message: Message
@@ -32,7 +32,7 @@ function SelectPrompt<T>({
   if (choices.length === 0) {
     throw new Error('SelectPrompt requires at least one choice')
   }
-  const complete = useComplete()
+  const {exit: unmountInk} = useApp()
   const {promptState, setPromptState, answer, setAnswer} = usePrompt<SelectItem<T> | undefined>({
     initialAnswer: undefined,
   })
@@ -47,10 +47,10 @@ function SelectPrompt<T>({
 
   useEffect(() => {
     if (promptState === PromptState.Submitted && answer) {
+      unmountInk()
       onSubmit(answer.value)
-      complete()
     }
-  }, [answer, onSubmit, promptState, complete])
+  }, [answer, onSubmit, promptState, unmountInk])
 
   return (
     <PromptLayout
diff --git a/packages/cli-kit/src/private/node/ui/components/SingleTask.tsx b/packages/cli-kit/src/private/node/ui/components/SingleTask.tsx
index 591800c1f0b..a58113df20f 100644
--- a/packages/cli-kit/src/private/node/ui/components/SingleTask.tsx
+++ b/packages/cli-kit/src/private/node/ui/components/SingleTask.tsx
@@ -1,9 +1,9 @@
 import {LoadingBar} from './LoadingBar.js'
-import {handleCtrlC, useComplete} from '../../ui.js'
+import {handleCtrlC} from '../../ui.js'
 import {TokenizedString} from '../../../../public/node/output.js'
 import React, {useEffect, useState} from 'react'
 
-import {useInput, useStdin} from 'ink'
+import {useApp, useInput, useStdin} from 'ink'
 
 interface SingleTaskProps<T> {
   title: TokenizedString
@@ -16,8 +16,7 @@ interface SingleTaskProps<T> {
 const SingleTask = <T,>({task, title, onComplete, onAbort, noColor}: SingleTaskProps<T>) => {
   const [status, setStatus] = useState(title)
   const [isDone, setIsDone] = useState(false)
-  const [taskResult, setTaskResult] = useState<{error?: Error} | null>(null)
-  const complete = useComplete()
+  const {exit: unmountInk} = useApp()
   const {isRawModeSupported} = useStdin()
 
   useInput(
@@ -36,19 +35,13 @@ const SingleTask = <T,>({task, title, onComplete, onAbort, noColor}: SingleTaskP
       .then((result) => {
         setIsDone(true)
         onComplete?.(result)
-        setTaskResult({})
+        unmountInk()
       })
       .catch((error) => {
         setIsDone(true)
-        setTaskResult({error})
+        unmountInk(error)
       })
-  }, [task, onComplete])
-
-  useEffect(() => {
-    if (taskResult !== null) {
-      complete(taskResult.error)
-    }
-  }, [taskResult, complete])
+  }, [task, unmountInk, onComplete])
 
   if (isDone) {
     // clear things once done
diff --git a/packages/cli-kit/src/private/node/ui/components/TextPrompt.tsx b/packages/cli-kit/src/private/node/ui/components/TextPrompt.tsx
index 6e398a324a9..d9d94e586da 100644
--- a/packages/cli-kit/src/private/node/ui/components/TextPrompt.tsx
+++ b/packages/cli-kit/src/private/node/ui/components/TextPrompt.tsx
@@ -1,6 +1,6 @@
 import {InlineToken, TokenItem, TokenizedText} from './TokenizedText.js'
 import {TextInput} from './TextInput.js'
-import {handleCtrlC, useComplete} from '../../ui.js'
+import {handleCtrlC} from '../../ui.js'
 import useLayout from '../hooks/use-layout.js'
 import {messageWithPunctuation} from '../utilities.js'
 import {AbortSignal} from '../../../../public/node/abort.js'
@@ -8,7 +8,7 @@ import useAbortSignal from '../hooks/use-abort-signal.js'
 import usePrompt, {PromptState} from '../hooks/use-prompt.js'
 import React, {FunctionComponent, useCallback, useEffect, useState} from 'react'
 
-import {Box, useInput, Text} from 'ink'
+import {Box, useApp, useInput, Text} from 'ink'
 import figures from 'figures'
 
 export interface TextPromptProps {
@@ -60,7 +60,7 @@ const TextPrompt: FunctionComponent<TextPromptProps> = ({
   const answerOrDefault = answer.length > 0 ? answer : defaultValue
   const displayEmptyValue = answerOrDefault === ''
   const displayedAnswer = displayEmptyValue ? emptyDisplayedValue : answerOrDefault
-  const complete = useComplete()
+  const {exit: unmountInk} = useApp()
   const [error, setError] = useState<string | undefined>(undefined)
   const color = promptState === PromptState.Error ? 'red' : 'cyan'
   const underline = new Array(oneThird - 3).fill('▔')
@@ -84,9 +84,9 @@ const TextPrompt: FunctionComponent<TextPromptProps> = ({
   useEffect(() => {
     if (promptState === PromptState.Submitted) {
       onSubmit(answerOrDefault)
-      complete()
+      unmountInk()
     }
-  }, [answerOrDefault, onSubmit, promptState, complete])
+  }, [answerOrDefault, onSubmit, promptState, unmountInk])
 
   return isAborted ? null : (
     <Box flexDirection="column" marginBottom={1} width={oneThird}>
diff --git a/packages/cli-kit/src/private/node/ui/hooks/use-abort-signal.ts b/packages/cli-kit/src/private/node/ui/hooks/use-abort-signal.ts
index a2b782b21ed..3cd216ad98f 100644
--- a/packages/cli-kit/src/private/node/ui/hooks/use-abort-signal.ts
+++ b/packages/cli-kit/src/private/node/ui/hooks/use-abort-signal.ts
@@ -1,28 +1,32 @@
 import {AbortSignal} from '../../../../public/node/abort.js'
-import {useComplete} from '../../ui.js'
-import {useEffect, useLayoutEffect, useState} from 'react'
+import {useApp} from 'ink'
+import {useLayoutEffect, useState} from 'react'
 
 const noop = () => Promise.resolve()
 
 export default function useAbortSignal(abortSignal?: AbortSignal, onAbort: (error?: unknown) => Promise<void> = noop) {
-  const complete = useComplete()
+  const {exit: unmountInk} = useApp()
   const [isAborted, setIsAborted] = useState(false)
 
   useLayoutEffect(() => {
     abortSignal?.addEventListener('abort', () => {
       const abortWithError = abortSignal.reason.message === 'AbortError' ? undefined : abortSignal.reason
       onAbort(abortWithError)
-        .then(() => setIsAborted(true))
+        .then(() => {
+          setIsAborted(true)
+          // Defer unmounting to the next setImmediate so React 19 can flush
+          // batched state updates before the tree is torn down.  React 19's
+          // scheduler also uses setImmediate in Node.js (check phase), and
+          // since it was queued first (by setIsAborted above), it renders
+          // before this callback fires (FIFO within the check phase).
+          // NOTE: setTimeout(fn, 0) is NOT safe here because its timers-phase
+          // fires BEFORE the check phase on slow CI machines where >1 ms has
+          // elapsed, causing unmount to race ahead of the render.
+          setImmediate(() => unmountInk(abortWithError))
+        })
         .catch(() => {})
     })
   }, [])
 
-  useEffect(() => {
-    if (isAborted) {
-      const abortWithError = abortSignal?.reason?.message === 'AbortError' ? undefined : abortSignal?.reason
-      complete(abortWithError)
-    }
-  }, [isAborted])
-
   return {isAborted}
 }
diff --git a/packages/cli-kit/src/private/node/ui/hooks/use-async-and-unmount.ts b/packages/cli-kit/src/private/node/ui/hooks/use-async-and-unmount.ts
index 9ba9e5ef26e..d2ed970f157 100644
--- a/packages/cli-kit/src/private/node/ui/hooks/use-async-and-unmount.ts
+++ b/packages/cli-kit/src/private/node/ui/hooks/use-async-and-unmount.ts
@@ -1,5 +1,5 @@
-import {useComplete} from '../../ui.js'
-import {useEffect, useState} from 'react'
+import {useApp} from 'ink'
+import {useEffect} from 'react'
 
 interface Options {
   onFulfilled?: () => unknown
@@ -10,24 +10,17 @@ export default function useAsyncAndUnmount(
   asyncFunction: () => Promise<unknown>,
   {onFulfilled = () => {}, onRejected = () => {}}: Options = {},
 ) {
-  const complete = useComplete()
-  const [result, setResult] = useState<{error?: Error} | null>(null)
+  const {exit: unmountInk} = useApp()
 
   useEffect(() => {
     asyncFunction()
       .then(() => {
         onFulfilled()
-        setResult({})
+        unmountInk()
       })
       .catch((error) => {
         onRejected(error)
-        setResult({error})
+        unmountInk(error)
       })
   }, [])
-
-  useEffect(() => {
-    if (result !== null) {
-      complete(result.error)
-    }
-  }, [result])
 }
diff --git a/packages/cli-kit/src/public/node/ui.test.ts b/packages/cli-kit/src/public/node/ui.test.ts
index a4dc1797043..f119b5de08c 100644
--- a/packages/cli-kit/src/public/node/ui.test.ts
+++ b/packages/cli-kit/src/public/node/ui.test.ts
@@ -504,31 +504,3 @@ describe('renderSingleTask', async () => {
     expect(result3).toBe('result3')
   })
 })
-
-describe('sequential renders', () => {
-  test('consecutive renders do not interleave or leak teardown output', async () => {
-    const output = mockAndCaptureOutput()
-
-    await renderTasks([
-      {
-        title: 'First batch',
-        task: async () => {
-          await new Promise((resolve) => setTimeout(resolve, 50))
-        },
-      },
-    ])
-
-    await renderSingleTask({
-      title: new TokenizedString('Second batch'),
-      task: async () => {
-        await new Promise((resolve) => setTimeout(resolve, 50))
-        return 'done'
-      },
-    })
-
-    // The key assertion: no interleaving. The second render's output should
-    // not contain fragments from the first render's teardown.
-    const frames = output.output()
-    expect(frames).not.toContain('First batch')
-  })
-})
diff --git a/packages/theme/src/cli/services/init.test.ts b/packages/theme/src/cli/services/init.test.ts
index 1f8466ebc44..eb79893e22f 100644
--- a/packages/theme/src/cli/services/init.test.ts
+++ b/packages/theme/src/cli/services/init.test.ts
@@ -27,13 +27,6 @@ vi.mock('@shopify/cli-kit/node/ui', async () => {
   return {
     ...actual,
     renderSelectPrompt: vi.fn(),
-    renderTasks: vi.fn(async (tasks: any[]) => {
-      for (const task of tasks) {
-        // eslint-disable-next-line no-await-in-loop
-        await task.task({}, task)
-      }
-      return {}
-    }),
   }
 })
 
diff --git a/packages/theme/src/cli/utilities/theme-downloader.test.ts b/packages/theme/src/cli/utilities/theme-downloader.test.ts
index 6bb6fe27657..530b7434f88 100644
--- a/packages/theme/src/cli/utilities/theme-downloader.test.ts
+++ b/packages/theme/src/cli/utilities/theme-downloader.test.ts
@@ -6,19 +6,6 @@ import {test, describe, expect, vi} from 'vitest'
 
 vi.mock('./theme-fs.js')
 vi.mock('@shopify/cli-kit/node/themes/api')
-vi.mock('@shopify/cli-kit/node/ui', async () => {
-  const actual = await vi.importActual('@shopify/cli-kit/node/ui')
-  return {
-    ...actual,
-    renderTasks: vi.fn(async (tasks: any[]) => {
-      for (const task of tasks) {
-        // eslint-disable-next-line no-await-in-loop
-        await task.task({}, task)
-      }
-      return {}
-    }),
-  }
-})
 
 describe('theme-downloader', () => {
   describe('downloadTheme', () => {