diff --git a/dsh-plugin-desktop-beta/src/desktop-runtime-environment.ts b/dsh-plugin-desktop-beta/src/desktop-runtime-environment.ts
index 6f18f8856f..8ec8f7fcd7 100644
--- a/dsh-plugin-desktop-beta/src/desktop-runtime-environment.ts
+++ b/dsh-plugin-desktop-beta/src/desktop-runtime-environment.ts
@@ -1,17 +1,17 @@
 /** App-local command environments available to desktop Host plugins. */
 
-import { randomUUID } from 'node:crypto'
+import { createHash, randomUUID } from 'node:crypto'
 import {
   chmodSync,
   lstatSync,
   mkdirSync,
+  readFileSync,
   readdirSync,
   renameSync,
-  unlinkSync,
+  rmSync,
   writeFileSync,
 } from 'node:fs'
-import { basename, dirname, join } from 'node:path'
-import { pathToFileURL } from 'node:url'
+import { join, win32 as windowsPath } from 'node:path'
 import { PNPM_IGNORE_MINIMUM_RELEASE_AGE } from './pnpm-policy.ts'
 import { assertDesktopProfileName } from './profile-manager.ts'
 
@@ -23,7 +23,9 @@ const ELECTRON_HEADERS_URL = 'https://electronjs.org/headers'
 const DIRECTORY_MODE = 0o700
 const EXECUTABLE_FILE_MODE = 0o700
 const PRIVATE_FILE_MODE = 0o600
-const TEMPORARY_ID = /^\d+\.[0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/u
+const GENERATION_SCHEMA_VERSION = 1
+const GENERATION_NAME = /^(?<hash>[0-9a-f]{64})-[0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/u
+const MANIFEST_NAME = '.generation.json'
 
 /** Inputs used to install one app-local pnpm command environment. */
 export interface DesktopPnpmRuntimeOptions {
@@ -31,7 +33,7 @@ export interface DesktopPnpmRuntimeOptions {
   platform: NodeJS.Platform
   /** Electron executable reused in RunAsNode mode. */
   appExecutable: string
-  /** Physical packaged pnpm JavaScript entry. */
+  /** Packaged pnpm JavaScript entry executable by Electron RunAsNode, including an ASAR logical path. */
   pnpmBinPath: string
   /** Electron version used when pnpm installs native dependencies. */
   electronVersion: string
@@ -106,16 +108,6 @@ function escapeBatchSetValue(value: string): string {
   return value.replaceAll('%', '%%')
 }
 
-/** Return one lstat result, preserving every failure except absence. */
-function lstatOptional(filename: string): ReturnType<typeof lstatSync> | undefined {
-  try {
-    return lstatSync(filename)
-  } catch (cause) {
-    if ((cause as NodeJS.ErrnoException).code === 'ENOENT') return undefined
-    throw cause
-  }
-}
-
 /** Create one owner-only real directory and reject a pre-existing alternate file type. */
 function preparePrivateDirectory(directory: string): void {
   mkdirSync(directory, { recursive: true, mode: DIRECTORY_MODE })
@@ -126,77 +118,221 @@ function preparePrivateDirectory(directory: string): void {
   chmodSync(directory, DIRECTORY_MODE)
 }
 
-/** Reject command-directory entries not owned by this runtime generation. */
-function assertOwnedDirectoryEntries(directory: string, allowed: readonly string[]): void {
-  const unexpected = readdirSync(directory).filter(entry => !allowed.includes(entry))
-  if (unexpected.length > 0) {
-    throw new Error(
-      `dsh-plugin-desktop: command runtime directory contains unexpected entries: ${unexpected.join(', ')}`,
-    )
+type RuntimeGenerationKind = 'dsh' | 'pnpm'
+
+interface RuntimeArtifact {
+  relativePath: string
+  contents: string
+  mode: number
+}
+
+interface RuntimeGenerationManifest {
+  schemaVersion: typeof GENERATION_SCHEMA_VERSION
+  kind: RuntimeGenerationKind
+  platform: NodeJS.Platform
+  contentHash: string
+  files: Array<{
+    path: string
+    sha256: string
+    mode: number
+  }>
+}
+
+interface RuntimeGenerationPlan {
+  kind: RuntimeGenerationKind
+  platform: NodeJS.Platform
+  contentHash: string
+  directories: string[]
+  artifacts: RuntimeArtifact[]
+}
+
+interface RuntimeGeneration {
+  root: string
+  obsoletePathDirectories: string[]
+}
+
+/** Hash deterministic generated content without depending on its eventual directory name. */
+function sha256(value: string): string {
+  return createHash('sha256').update(value, 'utf8').digest('hex')
+}
+
+/** Create a content-addressed plan and its self-describing ownership marker. */
+function runtimeGenerationPlan(
+  kind: RuntimeGenerationKind,
+  platform: NodeJS.Platform,
+  directories: readonly string[],
+  artifacts: readonly RuntimeArtifact[],
+): RuntimeGenerationPlan {
+  const orderedDirectories = [...directories].sort()
+  const orderedArtifacts = [...artifacts].sort((left, right) => left.relativePath.localeCompare(right.relativePath))
+  const contentHash = sha256(JSON.stringify({
+    schemaVersion: GENERATION_SCHEMA_VERSION,
+    kind,
+    platform,
+    directories: orderedDirectories,
+    files: orderedArtifacts.map(artifact => ({
+      path: artifact.relativePath,
+      contents: artifact.contents,
+      mode: artifact.mode,
+    })),
+  }))
+  const manifest: RuntimeGenerationManifest = {
+    schemaVersion: GENERATION_SCHEMA_VERSION,
+    kind,
+    platform,
+    contentHash,
+    files: orderedArtifacts.map(artifact => ({
+      path: artifact.relativePath,
+      sha256: sha256(artifact.contents),
+      mode: artifact.mode,
+    })),
+  }
+  return {
+    kind,
+    platform,
+    contentHash,
+    directories: orderedDirectories,
+    artifacts: [
+      { relativePath: MANIFEST_NAME, contents: `${JSON.stringify(manifest, undefined, 2)}\n`, mode: PRIVATE_FILE_MODE },
+      ...orderedArtifacts,
+    ],
   }
 }
 
-/** Remove one stray command entry without recursively deleting unknown data. */
-function removeUnexpectedEntry(directory: string, entry: string): void {
-  const filename = join(directory, entry)
-  if (lstatSync(filename).isDirectory()) {
-    throw new Error(
-      `dsh-plugin-desktop: command runtime contains an unexpected directory: ${entry}`,
-    )
-  }
-  process.stderr.write(
-    `dsh-plugin-desktop: removing unexpected command runtime entry ${JSON.stringify(entry)}\n`,
-  )
-  unlinkSync(filename)
+function pathSegments(relativePath: string): string[] {
+  return relativePath.split('/')
 }
 
-/** Recover an app-owned command directory to this generation's exact contents. */
-function reconcileOwnedDirectoryEntries(directory: string, allowed: readonly string[]): void {
-  for (const entry of readdirSync(directory)) {
-    if (!allowed.includes(entry)) removeUnexpectedEntry(directory, entry)
-  }
+function generationPath(root: string, relativePath: string): string {
+  return join(root, ...pathSegments(relativePath))
 }
 
-/** Remove only stale atomic-write files generated for one exact target name. */
-function removeStaleTemporaryFiles(directory: string, targetName: string): void {
-  const prefix = `.${targetName}.`
-  const suffix = '.tmp'
-  for (const entry of readdirSync(directory)) {
-    if (!entry.startsWith(prefix) || !entry.endsWith(suffix)) continue
-    const identity = entry.slice(prefix.length, -suffix.length)
-    if (!TEMPORARY_ID.test(identity)) continue
-    const filename = join(directory, entry)
-    const stat = lstatSync(filename)
-    if (!stat.isFile() && !stat.isSymbolicLink()) {
-      throw new Error(`dsh-plugin-desktop: command runtime stale temporary path is not a file: ${filename}`)
+/** Inspect a generation tree without following symlinks. */
+function generationTree(root: string): { directories: string[]; files: string[] } | undefined {
+  try {
+    const rootStat = lstatSync(root)
+    if (!rootStat.isDirectory() || rootStat.isSymbolicLink()) return undefined
+    const directories: string[] = []
+    const files: string[] = []
+    const visit = (directory: string, prefix: string): boolean => {
+      for (const entry of readdirSync(directory)) {
+        const relativePath = prefix.length === 0 ? entry : `${prefix}/${entry}`
+        const stat = lstatSync(join(directory, entry))
+        if (stat.isSymbolicLink()) return false
+        if (stat.isDirectory()) {
+          directories.push(relativePath)
+          if (!visit(join(directory, entry), relativePath)) return false
+          continue
+        }
+        if (!stat.isFile()) return false
+        files.push(relativePath)
+      }
+      return true
     }
-    unlinkSync(filename)
+    if (!visit(root, '')) return undefined
+    return { directories: directories.sort(), files: files.sort() }
+  } catch {
+    return undefined
   }
 }
 
-/** Remove a temporary file while preserving every failure except absence. */
-function unlinkTemporaryFile(filename: string): void {
+function sameStrings(left: readonly string[], right: readonly string[]): boolean {
+  return left.length === right.length && left.every((value, index) => value === right[index])
+}
+
+/** Verify exact content before making an existing immutable generation executable via PATH. */
+function reusableGeneration(root: string, plan: RuntimeGenerationPlan): boolean {
+  const tree = generationTree(root)
+  if (tree === undefined) return false
+  const expectedFiles = plan.artifacts.map(artifact => artifact.relativePath).sort()
+  if (!sameStrings(tree.directories, plan.directories) || !sameStrings(tree.files, expectedFiles)) return false
   try {
-    unlinkSync(filename)
+    for (const artifact of plan.artifacts) {
+      const filename = generationPath(root, artifact.relativePath)
+      const stat = lstatSync(filename)
+      if (!stat.isFile() || stat.isSymbolicLink()) return false
+      if (process.platform !== 'win32' && (stat.mode & 0o777) !== artifact.mode) return false
+      if (readFileSync(filename, 'utf8') !== artifact.contents) return false
+    }
+    return true
+  } catch {
+    return false
+  }
+}
+
+function reportCleanupFailure(filename: string, cause: unknown): void {
+  const code = (cause as NodeJS.ErrnoException).code
+  try {
+    process.stderr.write(
+      `dsh-plugin-desktop: deferred command runtime cleanup for ${JSON.stringify(filename)}`
+        + `${code === undefined ? '' : ` (${code})`}\n`,
+    )
+  } catch {
+    // Diagnostics must not turn best-effort generation cleanup into a startup failure.
+  }
+}
+
+/** Materialize a new generation privately, then publish it under a never-reused name. */
+function createRuntimeGeneration(generationsDir: string, plan: RuntimeGenerationPlan): string {
+  const temporaryRoot = join(generationsDir, `.staging.${process.pid}.${randomUUID()}`)
+  mkdirSync(temporaryRoot, { mode: DIRECTORY_MODE })
+  chmodSync(temporaryRoot, DIRECTORY_MODE)
+  try {
+    for (const relativePath of [...plan.directories].sort((left, right) => {
+      return pathSegments(left).length - pathSegments(right).length || left.localeCompare(right)
+    })) {
+      const directory = generationPath(temporaryRoot, relativePath)
+      mkdirSync(directory, { mode: DIRECTORY_MODE })
+      chmodSync(directory, DIRECTORY_MODE)
+    }
+    for (const artifact of plan.artifacts) {
+      const filename = generationPath(temporaryRoot, artifact.relativePath)
+      writeFileSync(filename, artifact.contents, { encoding: 'utf8', flag: 'wx', mode: artifact.mode })
+      chmodSync(filename, artifact.mode)
+    }
+    const root = join(generationsDir, `${plan.contentHash}-${randomUUID()}`)
+    renameSync(temporaryRoot, root)
+    return root
   } catch (cause) {
-    if ((cause as NodeJS.ErrnoException).code !== 'ENOENT') throw cause
+    try {
+      rmSync(temporaryRoot, { recursive: true, force: true, maxRetries: 0 })
+    } catch (cleanupCause) {
+      reportCleanupFailure(temporaryRoot, cleanupCause)
+    }
+    throw cause
   }
 }
 
-/** Atomically replace one regular app-owned file without accepting a symlink target. */
-function replacePrivateFile(filename: string, contents: string, mode: number): void {
-  const existing = lstatOptional(filename)
-  if (existing !== undefined && (!existing.isFile() || existing.isSymbolicLink())) {
-    throw new Error(`dsh-plugin-desktop: command runtime file is not a regular file: ${filename}`)
-  }
-  const temporary = join(dirname(filename), `.${basename(filename)}.${process.pid}.${randomUUID()}.tmp`)
-  try {
-    writeFileSync(temporary, contents, { encoding: 'utf8', flag: 'wx', mode })
-    chmodSync(temporary, mode)
-    renameSync(temporary, filename)
-  } finally {
-    unlinkTemporaryFile(temporary)
+/** Reuse an exact immutable generation or publish a clean sibling when any candidate is tainted. */
+function installRuntimeGeneration(stateDir: string, plan: RuntimeGenerationPlan): RuntimeGeneration {
+  preparePrivateDirectory(stateDir)
+  const generationsDir = join(stateDir, 'generations')
+  preparePrivateDirectory(generationsDir)
+  const entries = readdirSync(generationsDir)
+  let root: string | undefined
+  for (const entry of entries.sort()) {
+    const match = GENERATION_NAME.exec(entry)
+    if (match?.groups?.hash !== plan.contentHash) continue
+    const candidate = join(generationsDir, entry)
+    if (reusableGeneration(candidate, plan)) {
+      root = candidate
+      break
+    }
   }
+  root ??= createRuntimeGeneration(generationsDir, plan)
+  const obsoletePathDirectories = [
+    join(stateDir, 'bin'),
+    join(stateDir, 'private', 'node-bin'),
+    ...entries.flatMap(entry => [
+      join(generationsDir, entry, 'bin'),
+      join(generationsDir, entry, 'private', 'node-bin'),
+    ]),
+  ].filter(directory => {
+    return directory !== join(root, 'bin') && directory !== join(root, 'private', 'node-bin')
+  })
+  // Published generations may still back child processes after the desktop lifecycle advances.
+  // Keep them immutable and isolate them from PATH; safe garbage collection requires explicit leases.
+  return { root, obsoletePathDirectories }
 }
 
 /** Module preloaded into RunAsNode children before their requested entry. */
@@ -210,65 +346,68 @@ function clearEnvironmentModule(): string {
 }
 
 /** Build the private POSIX Node command used only by pnpm lifecycle scripts. */
-function posixNodeShim(appExecutable: string, clearEnvironmentUrl: string): string {
+function posixNodeShim(appExecutable: string): string {
   return [
     '#!/bin/sh',
-    `${RUN_AS_NODE}=1 exec ${quoteSh(appExecutable)} --import ${quoteSh(clearEnvironmentUrl)} "$@"`,
+    'runtime_node_bin_dir=${0%/*}',
+    'runtime_private_dir=${runtime_node_bin_dir%/*}',
+    'runtime_clear_environment="$runtime_private_dir/clear-env.cjs"',
+    `${RUN_AS_NODE}=1 exec ${quoteSh(appExecutable)} --require "$runtime_clear_environment" "$@"`,
     '',
   ].join('\n')
 }
 
 /** Build the public POSIX pnpm command. */
-function posixPnpmShim(
-  options: DesktopPnpmRuntimeOptions,
-  nodeBinDir: string,
-  nodeShimPath: string,
-  clearEnvironmentUrl: string,
-): string {
+function posixPnpmShim(options: DesktopPnpmRuntimeOptions): string {
   return [
     '#!/bin/sh',
+    'runtime_public_dir=${0%/*}',
+    'runtime_root_dir=${runtime_public_dir%/*}',
+    'runtime_private_dir="$runtime_root_dir/private"',
+    'runtime_node_bin_dir="$runtime_private_dir/node-bin"',
+    'runtime_node_shim="$runtime_node_bin_dir/node"',
+    'runtime_clear_environment="$runtime_private_dir/clear-env.cjs"',
     [
-      `PATH=${quoteSh(nodeBinDir)}:"\${PATH:-}"`,
-      `NODE=${quoteSh(nodeShimPath)}`,
+      'PATH="$runtime_node_bin_dir:${PATH:-}"',
+      'NODE="$runtime_node_shim"',
       `${RUN_AS_NODE}=1`,
       'npm_config_runtime=electron',
       `npm_config_target=${quoteSh(options.electronVersion)}`,
       `npm_config_disturl=${quoteSh(ELECTRON_HEADERS_URL)}`,
-      `exec ${quoteSh(options.appExecutable)} --import ${quoteSh(clearEnvironmentUrl)} ${quoteSh(options.pnpmBinPath)} ${PNPM_IGNORE_MINIMUM_RELEASE_AGE} "$@"`,
+      `exec ${quoteSh(options.appExecutable)} --require "$runtime_clear_environment" ${quoteSh(options.pnpmBinPath)} ${PNPM_IGNORE_MINIMUM_RELEASE_AGE} "$@"`,
     ].join(' '),
     '',
   ].join('\n')
 }
 
 /** Build the private Windows Node command used only by pnpm lifecycle scripts. */
-function windowsNodeShim(appExecutable: string, clearEnvironmentUrl: string): string {
+function windowsNodeShim(appExecutable: string): string {
   return [
     '@echo off',
     'setlocal DisableDelayedExpansion',
+    'set "DSH_RUNTIME_PRIVATE=%~dp0.."',
     `set "${RUN_AS_NODE}=1"`,
-    `${quoteBatchWord(appExecutable)} --import ${quoteBatchWord(clearEnvironmentUrl)} %*`,
+    `${quoteBatchWord(appExecutable)} --require "%DSH_RUNTIME_PRIVATE%\\clear-env.cjs" %*`,
     'exit /b %errorlevel%',
     '',
   ].join('\r\n')
 }
 
 /** Build the public Windows pnpm command. */
-function windowsPnpmShim(
-  options: DesktopPnpmRuntimeOptions,
-  nodeBinDir: string,
-  nodeShimPath: string,
-  clearEnvironmentUrl: string,
-): string {
+function windowsPnpmShim(options: DesktopPnpmRuntimeOptions): string {
   return [
     '@echo off',
     'setlocal DisableDelayedExpansion',
-    `set "PATH=${escapeBatchSetValue(nodeBinDir)};%PATH%"`,
-    `set "NODE=${escapeBatchSetValue(nodeShimPath)}"`,
+    'set "DSH_RUNTIME_ROOT=%~dp0.."',
+    'set "DSH_RUNTIME_PRIVATE=%DSH_RUNTIME_ROOT%\\private"',
+    'set "DSH_RUNTIME_NODE_BIN=%DSH_RUNTIME_PRIVATE%\\node-bin"',
+    'set "PATH=%DSH_RUNTIME_NODE_BIN%;%PATH%"',
+    'set "NODE=%DSH_RUNTIME_NODE_BIN%\\node.cmd"',
     `set "${RUN_AS_NODE}=1"`,
     'set "npm_config_runtime=electron"',
     `set "npm_config_target=${escapeBatchSetValue(options.electronVersion)}"`,
     `set "npm_config_disturl=${ELECTRON_HEADERS_URL}"`,
-    `${quoteBatchWord(options.appExecutable)} --import ${quoteBatchWord(clearEnvironmentUrl)} ${quoteBatchWord(options.pnpmBinPath)} ${PNPM_IGNORE_MINIMUM_RELEASE_AGE} %*`,
+    `${quoteBatchWord(options.appExecutable)} --require "%DSH_RUNTIME_PRIVATE%\\clear-env.cjs" ${quoteBatchWord(options.pnpmBinPath)} ${PNPM_IGNORE_MINIMUM_RELEASE_AGE} %*`,
     'exit /b %errorlevel%',
     '',
   ].join('\r\n')
@@ -305,7 +444,13 @@ function normalizedPathComponent(component: string, platform: NodeJS.Platform):
   const unquoted = platform === 'win32' && component.startsWith('"') && component.endsWith('"')
     ? component.slice(1, -1)
     : component
-  return platform === 'win32' ? unquoted.toLowerCase() : unquoted
+  if (platform !== 'win32' || unquoted.length === 0) return unquoted
+  const normalized = windowsPath.normalize(unquoted)
+  const root = windowsPath.parse(normalized).root
+  const withoutTrailingSeparators = normalized.length > root.length
+    ? normalized.replace(/[\\/]+$/u, '')
+    : normalized
+  return withoutTrailingSeparators.toLowerCase()
 }
 
 /** Remove every occurrence of one directory from a PATH value. */
@@ -323,18 +468,21 @@ function installPathDirectory(
   environment: NodeJS.ProcessEnv,
   directory: string,
   platform: NodeJS.Platform,
+  obsoleteDirectories: readonly string[] = [],
 ): () => void {
   const original = pathEntries(environment, platform)
   const current = original.find(entry => entry.value !== undefined)
   const currentValue = current?.value ?? ''
   const key = current?.key ?? PATH
   const delimiter = platform === 'win32' ? ';' : ':'
-  const inheritedValue = withoutPathDirectory(currentValue, directory, platform)
-  const firstComponent = currentValue.split(delimiter)[0] ?? ''
-  if (normalizedPathComponent(firstComponent, platform) === normalizedPathComponent(directory, platform)) {
+  const inheritedValue = [directory, ...obsoleteDirectories].reduce(
+    (value, candidate) => withoutPathDirectory(value, candidate, platform),
+    currentValue,
+  )
+  const installedValue = inheritedValue.length === 0 ? directory : `${directory}${delimiter}${inheritedValue}`
+  if (installedValue === currentValue) {
     return () => {}
   }
-  const installedValue = inheritedValue.length === 0 ? directory : `${directory}${delimiter}${inheritedValue}`
   for (const entry of original) delete environment[entry.key]
   environment[key] = installedValue
 
@@ -368,18 +516,24 @@ export function installDesktopDshRuntime(options: DesktopDshRuntimeOptions): Des
     ['state directory', options.stateDir],
   ] as const) assertScriptValue(label, value)
 
-  const pathDir = join(options.stateDir, 'bin')
-  preparePrivateDirectory(options.stateDir)
-  preparePrivateDirectory(pathDir)
-  removeStaleTemporaryFiles(pathDir, 'dsh.cmd')
-  assertOwnedDirectoryEntries(pathDir, ['dsh.cmd'])
+  const plan = runtimeGenerationPlan('dsh', options.platform, ['bin'], [{
+    relativePath: 'bin/dsh.cmd',
+    contents: windowsDshShim(options),
+    mode: PRIVATE_FILE_MODE,
+  }])
+  const generation = installRuntimeGeneration(options.stateDir, plan)
+  const pathDir = join(generation.root, 'bin')
   const dshShimPath = join(pathDir, 'dsh.cmd')
-  replacePrivateFile(dshShimPath, windowsDshShim(options), PRIVATE_FILE_MODE)
 
   return {
     pathDir,
     dshShimPath,
-    dispose: installPathDirectory(options.environment ?? process.env, pathDir, options.platform),
+    dispose: installPathDirectory(
+      options.environment ?? process.env,
+      pathDir,
+      options.platform,
+      generation.obsoletePathDirectories,
+    ),
   }
 }
 
@@ -399,41 +553,38 @@ export function installDesktopPnpmRuntime(options: DesktopPnpmRuntimeOptions): D
     ['state directory', options.stateDir],
   ] as const) assertScriptValue(label, value)
 
-  const pathDir = join(options.stateDir, 'bin')
-  const privateDir = join(options.stateDir, 'private')
-  const nodeBinDir = join(privateDir, 'node-bin')
-  preparePrivateDirectory(options.stateDir)
-  preparePrivateDirectory(pathDir)
-  preparePrivateDirectory(privateDir)
-  preparePrivateDirectory(nodeBinDir)
-
   const windows = options.platform === 'win32'
   const pnpmShimName = windows ? 'pnpm.cmd' : 'pnpm'
   const nodeShimName = windows ? 'node.cmd' : 'node'
-  removeStaleTemporaryFiles(pathDir, pnpmShimName)
-  removeStaleTemporaryFiles(nodeBinDir, nodeShimName)
-  removeStaleTemporaryFiles(privateDir, 'clear-env.mjs')
-  reconcileOwnedDirectoryEntries(pathDir, [pnpmShimName])
-  reconcileOwnedDirectoryEntries(nodeBinDir, [nodeShimName])
+  const plan = runtimeGenerationPlan(
+    'pnpm',
+    options.platform,
+    ['bin', 'private', 'private/node-bin'],
+    [
+      {
+        relativePath: 'private/clear-env.cjs',
+        contents: clearEnvironmentModule(),
+        mode: PRIVATE_FILE_MODE,
+      },
+      {
+        relativePath: `private/node-bin/${nodeShimName}`,
+        contents: windows ? windowsNodeShim(options.appExecutable) : posixNodeShim(options.appExecutable),
+        mode: windows ? PRIVATE_FILE_MODE : EXECUTABLE_FILE_MODE,
+      },
+      {
+        relativePath: `bin/${pnpmShimName}`,
+        contents: windows ? windowsPnpmShim(options) : posixPnpmShim(options),
+        mode: windows ? PRIVATE_FILE_MODE : EXECUTABLE_FILE_MODE,
+      },
+    ],
+  )
+  const generation = installRuntimeGeneration(options.stateDir, plan)
+  const pathDir = join(generation.root, 'bin')
+  const privateDir = join(generation.root, 'private')
+  const nodeBinDir = join(privateDir, 'node-bin')
   const pnpmShimPath = join(pathDir, pnpmShimName)
   const nodeShimPath = join(nodeBinDir, nodeShimName)
-  const clearEnvironmentPath = join(privateDir, 'clear-env.mjs')
-  replacePrivateFile(clearEnvironmentPath, clearEnvironmentModule(), PRIVATE_FILE_MODE)
-  const clearEnvironmentUrl = pathToFileURL(clearEnvironmentPath).href
-  replacePrivateFile(
-    nodeShimPath,
-    windows
-      ? windowsNodeShim(options.appExecutable, clearEnvironmentUrl)
-      : posixNodeShim(options.appExecutable, clearEnvironmentUrl),
-    windows ? PRIVATE_FILE_MODE : EXECUTABLE_FILE_MODE,
-  )
-  replacePrivateFile(
-    pnpmShimPath,
-    windows
-      ? windowsPnpmShim(options, nodeBinDir, nodeShimPath, clearEnvironmentUrl)
-      : posixPnpmShim(options, nodeBinDir, nodeShimPath, clearEnvironmentUrl),
-    windows ? PRIVATE_FILE_MODE : EXECUTABLE_FILE_MODE,
-  )
+  const clearEnvironmentPath = join(privateDir, 'clear-env.cjs')
 
   return {
     pathDir,
@@ -441,6 +592,11 @@ export function installDesktopPnpmRuntime(options: DesktopPnpmRuntimeOptions): D
     nodeBinDir,
     nodeShimPath,
     clearEnvironmentPath,
-    dispose: installPathDirectory(options.environment ?? process.env, pathDir, options.platform),
+    dispose: installPathDirectory(
+      options.environment ?? process.env,
+      pathDir,
+      options.platform,
+      generation.obsoletePathDirectories,
+    ),
   }
 }
diff --git a/dsh-plugin-desktop-beta/src/setup-wizard-settings.ts b/dsh-plugin-desktop-beta/src/setup-wizard-settings.ts
index de3b9f8980..932347f9c7 100644
--- a/dsh-plugin-desktop-beta/src/setup-wizard-settings.ts
+++ b/dsh-plugin-desktop-beta/src/setup-wizard-settings.ts
@@ -260,7 +260,8 @@ function normalizedUpdate(
   })
 }
 
-function sameSettings(
+/** Return whether two normalized Setup views have identical persisted leaves. */
+export function sameDesktopSetupWizardSettings(
   current: DesktopSetupWizardSettings,
   next: DesktopSetupWizardSettings,
 ): boolean {
@@ -341,7 +342,7 @@ export async function updateDesktopSetupWizardSettings(
   // Explicit default leaves do not need to be materialized. Apart from making
   // Setup idempotent, this lets an unchanged first-run choice proceed while an
   // unrelated or orphaned settings writer lock exists.
-  if (sameSettings(projectSettings(loadSettingsDocument(path).root), next)) return next
+  if (sameDesktopSetupWizardSettings(projectSettings(loadSettingsDocument(path).root), next)) return next
   ensureDocumentDirectory(path)
   const loaded = loadSettingsDocument(path)
   // Refuse to cover an invalid known value, including the inactive platform's
diff --git a/dsh-plugin-desktop-beta/tests/desktop-runtime-environment.spec.ts b/dsh-plugin-desktop-beta/tests/desktop-runtime-environment.spec.ts
index ecae801a11..9a2e83e370 100644
--- a/dsh-plugin-desktop-beta/tests/desktop-runtime-environment.spec.ts
+++ b/dsh-plugin-desktop-beta/tests/desktop-runtime-environment.spec.ts
@@ -1,5 +1,7 @@
 import { spawnSync } from 'node:child_process'
+import fs from 'node:fs'
 import {
+  existsSync,
   lstatSync,
   mkdirSync,
   mkdtempSync,
@@ -9,8 +11,9 @@ import {
   symlinkSync,
   writeFileSync,
 } from 'node:fs'
+import { syncBuiltinESMExports } from 'node:module'
 import { tmpdir } from 'node:os'
-import { delimiter as pathDelimiter, join } from 'node:path'
+import { basename, delimiter as pathDelimiter, dirname, join } from 'node:path'
 import { pathToFileURL } from 'node:url'
 import { afterEach, describe, expect, it, vi } from 'vitest'
 import {
@@ -68,6 +71,12 @@ describe('desktop Host pnpm runtime', () => {
 
     expect(readdirSync(installation.pathDir)).toEqual(['pnpm'])
     expect(readdirSync(installation.nodeBinDir)).toEqual(['node'])
+    const generationRoot = dirname(installation.pathDir)
+    const manifest = JSON.parse(readFileSync(join(generationRoot, '.generation.json'), 'utf8')) as {
+      contentHash: string
+    }
+    expect(readdirSync(generationRoot).sort()).toEqual(['.generation.json', 'bin', 'private'])
+    expect(basename(generationRoot)).toMatch(new RegExp(`^${manifest.contentHash}-`))
     if (process.platform !== 'win32') {
       expect(lstatSync(stateDir).mode & 0o777).toBe(0o700)
       expect(lstatSync(installation.pathDir).mode & 0o777).toBe(0o700)
@@ -77,20 +86,20 @@ describe('desktop Host pnpm runtime', () => {
       expect(lstatSync(installation.clearEnvironmentPath).mode & 0o777).toBe(0o600)
     }
 
-    const clearEnvironmentUrl = pathToFileURL(installation.clearEnvironmentPath).href
     const pnpm = readFileSync(installation.pnpmShimPath, 'utf8')
-    expect(pnpm).toContain(`PATH='${installation.nodeBinDir}':"\${PATH:-}"`)
-    expect(pnpm).toContain(`NODE='${installation.nodeShimPath}'`)
+    expect(pnpm).toContain('runtime_root_dir=${runtime_public_dir%/*}')
+    expect(pnpm).toContain('PATH="$runtime_node_bin_dir:${PATH:-}"')
+    expect(pnpm).toContain('NODE="$runtime_node_shim"')
     expect(pnpm).toContain('ELECTRON_RUN_AS_NODE=1 npm_config_runtime=electron')
     expect(pnpm).toContain("npm_config_target='43.4.0'")
     expect(pnpm).toContain("npm_config_disturl='https://electronjs.org/headers'")
     expect(pnpm.match(/--config\.minimumReleaseAge=0/gu)).toHaveLength(1)
     expect(pnpm).toContain('--config.minimumReleaseAge=0 "$@"')
-    expect(pnpm).toContain(`--import '${clearEnvironmentUrl}'`)
-    expect(pnpm.indexOf(`--import '${clearEnvironmentUrl}'`)).toBeLessThan(pnpm.indexOf('pnpm/bin/pnpm.mjs'))
+    expect(pnpm).toContain('--require "$runtime_clear_environment"')
+    expect(pnpm.indexOf('--require "$runtime_clear_environment"')).toBeLessThan(pnpm.indexOf('pnpm/bin/pnpm.mjs'))
     const node = readFileSync(installation.nodeShimPath, 'utf8')
     expect(node).toContain(`ELECTRON_RUN_AS_NODE=1 exec`)
-    expect(node).toContain(`--import '${clearEnvironmentUrl}' "$@"`)
+    expect(node).toContain('--require "$runtime_clear_environment" "$@"')
     expect(node).not.toContain('npm_config_')
     expect(readFileSync(installation.clearEnvironmentPath, 'utf8')).toContain(
       "name.toUpperCase() === 'ELECTRON_RUN_AS_NODE'",
@@ -178,7 +187,7 @@ describe('desktop Host pnpm runtime', () => {
 
     const command = process.platform === 'win32'
       ? process.env.ComSpec ?? 'cmd.exe'
-      : installation.pnpmShimPath
+      : 'pnpm'
     const args = process.platform === 'win32'
       ? ['/d', '/s', '/c', `""${installation.pnpmShimPath}" "${captureOutput}""`]
       : [captureOutput]
@@ -217,21 +226,22 @@ describe('desktop Host pnpm runtime', () => {
 
     expect(readdirSync(installation.pathDir)).toEqual(['pnpm.cmd'])
     expect(readdirSync(installation.nodeBinDir)).toEqual(['node.cmd'])
-    const clearEnvironmentUrl = pathToFileURL(installation.clearEnvironmentPath).href
-    const escapedClearEnvironmentUrl = clearEnvironmentUrl.replaceAll('%', '%%')
     const pnpm = readFileSync(installation.pnpmShimPath, 'utf8')
-    expect(pnpm).toContain(`set "PATH=${installation.nodeBinDir};%PATH%"`)
-    expect(pnpm).toContain(`set "NODE=${installation.nodeShimPath}"`)
+    expect(pnpm).toContain('set "DSH_RUNTIME_ROOT=%~dp0.."')
+    expect(pnpm).toContain('set "PATH=%DSH_RUNTIME_NODE_BIN%;%PATH%"')
+    expect(pnpm).toContain('set "NODE=%DSH_RUNTIME_NODE_BIN%\\node.cmd"')
     expect(pnpm).toContain('set "ELECTRON_RUN_AS_NODE=1"')
     expect(pnpm).toContain('set "npm_config_runtime=electron"')
     expect(pnpm).toContain('set "npm_config_target=43.4.0"')
-    expect(pnpm).toContain(`--import "${escapedClearEnvironmentUrl}"`)
-    expect(pnpm.indexOf(`--import "${escapedClearEnvironmentUrl}"`)).toBeLessThan(pnpm.indexOf('pnpm\\bin\\pnpm.mjs'))
+    expect(pnpm).toContain('--require "%DSH_RUNTIME_PRIVATE%\\clear-env.cjs"')
+    expect(pnpm.indexOf('--require "%DSH_RUNTIME_PRIVATE%\\clear-env.cjs"')).toBeLessThan(
+      pnpm.indexOf('pnpm\\bin\\pnpm.mjs'),
+    )
     expect(pnpm.match(/--config\.minimumReleaseAge=0/gu)).toHaveLength(1)
     expect(pnpm).toContain('--config.minimumReleaseAge=0 %*')
     const node = readFileSync(installation.nodeShimPath, 'utf8')
     expect(node).toContain('set "ELECTRON_RUN_AS_NODE=1"')
-    expect(node).toContain(`--import "${escapedClearEnvironmentUrl}" %*`)
+    expect(node).toContain('--require "%DSH_RUNTIME_PRIVATE%\\clear-env.cjs" %*')
     expect(node).not.toContain('npm_config_')
 
     expect(environment).toEqual({
@@ -261,6 +271,28 @@ describe('desktop Host pnpm runtime', () => {
     expect(environment).toEqual({ PATH: `${laterPath}${pathDelimiter}${originalPath}` })
   })
 
+  it('normalizes Windows separators and trailing separators when replacing legacy PATH entries', () => {
+    const root = temporaryDirectory()
+    const stateDir = join(root, 'runtime-commands')
+    const environment: NodeJS.ProcessEnv = { Path: 'C:\\Windows' }
+    const first = installDesktopPnpmRuntime(options(stateDir, 'win32', environment))
+    first.dispose()
+    const legacyPathDir = join(stateDir, 'bin')
+    mkdirSync(legacyPathDir, { recursive: true })
+    writeFileSync(join(legacyPathDir, 'bsk.exe'), 'legacy unknown command')
+    const legacyVariant = `${legacyPathDir.replaceAll('/', '\\')}\\`
+    const activeVariant = `${first.pathDir.replaceAll('/', '\\')}\\`
+    const systemPath = 'C:/Windows/System32/'
+    environment.Path = `"${legacyVariant}";"${activeVariant}";${systemPath}`
+
+    const second = installDesktopPnpmRuntime(options(stateDir, 'win32', environment))
+
+    expect(second.pathDir).toBe(first.pathDir)
+    expect(environment.Path).toBe(`${second.pathDir};${systemPath}`)
+    second.dispose()
+    expect(environment.Path).toBe(`"${legacyVariant}";"${activeVariant}";${systemPath}`)
+  })
+
   it.runIf(process.platform === 'win32')('reclaims PATH precedence from an inherited Desktop terminal shim', () => {
     const root = temporaryDirectory()
     const stateDir = join(root, 'runtime')
@@ -306,17 +338,24 @@ describe('desktop Host pnpm runtime', () => {
     expect(environment).toEqual(original)
   })
 
-  it('does not duplicate or remove a runtime already first on PATH', () => {
+  it('reuses an exact immutable generation without rewriting it', () => {
     const stateDir = join(temporaryDirectory(), 'runtime')
-    const pathDir = join(stateDir, 'bin')
     const platform = process.platform === 'win32' ? 'win32' : 'linux'
     const originalPath = process.platform === 'win32' ? 'C:\\Windows' : '/usr/bin'
-    const environment: NodeJS.ProcessEnv = { PATH: `${pathDir}${pathDelimiter}${originalPath}` }
-    const installation = installDesktopPnpmRuntime(options(stateDir, platform, environment))
+    const environment: NodeJS.ProcessEnv = { PATH: originalPath }
+    const first = installDesktopPnpmRuntime(options(stateDir, platform, environment))
+    const firstStat = lstatSync(first.pnpmShimPath)
+    first.dispose()
+    environment.PATH = `${first.pathDir}${pathDelimiter}${originalPath}`
 
-    expect(environment.PATH).toBe(`${pathDir}${pathDelimiter}${originalPath}`)
-    installation.dispose()
-    expect(environment.PATH).toBe(`${pathDir}${pathDelimiter}${originalPath}`)
+    const second = installDesktopPnpmRuntime(options(stateDir, platform, environment))
+
+    expect(second.pathDir).toBe(first.pathDir)
+    expect(lstatSync(second.pnpmShimPath).ino).toBe(firstStat.ino)
+    expect(lstatSync(second.pnpmShimPath).mtimeMs).toBe(firstStat.mtimeMs)
+    expect(environment.PATH).toBe(`${first.pathDir}${pathDelimiter}${originalPath}`)
+    second.dispose()
+    expect(environment.PATH).toBe(`${first.pathDir}${pathDelimiter}${originalPath}`)
   })
 
   it('rejects symlinked state directories before changing PATH', () => {
@@ -332,89 +371,86 @@ describe('desktop Host pnpm runtime', () => {
     expect(environment).toEqual({ PATH: '/usr/bin' })
   })
 
-  it('rejects a symlinked generated file before changing PATH', () => {
+  it('publishes a clean sibling instead of trusting a contaminated generation', () => {
     const root = temporaryDirectory()
     const stateDir = join(root, 'runtime')
-    const pathDir = join(stateDir, 'bin')
-    const privateDir = join(stateDir, 'private')
-    const nodeBinDir = join(privateDir, 'node-bin')
-    mkdirSync(pathDir, { recursive: true })
-    mkdirSync(nodeBinDir, { recursive: true })
+    const environment: NodeJS.ProcessEnv = { PATH: '/usr/bin' }
+    const first = installDesktopPnpmRuntime(options(stateDir, 'linux', environment))
+    first.dispose()
     const target = join(root, 'outside')
     writeFileSync(target, 'outside')
-    symlinkSync(target, join(pathDir, 'pnpm'))
-    const environment: NodeJS.ProcessEnv = { PATH: '/usr/bin' }
+    rmSync(first.pnpmShimPath)
+    symlinkSync(target, first.pnpmShimPath)
+    const unknownExecutable = join(first.pathDir, 'bsk.exe')
+    writeFileSync(unknownExecutable, 'locked or foreign')
+    environment.PATH = `${first.pathDir}:/usr/bin`
 
-    expect(() => installDesktopPnpmRuntime(options(stateDir, 'linux', environment)))
-      .toThrow('not a regular file')
+    const second = installDesktopPnpmRuntime(options(stateDir, 'linux', environment))
+
+    expect(second.pathDir).not.toBe(first.pathDir)
+    expect(readdirSync(second.pathDir)).toEqual(['pnpm'])
+    expect(environment.PATH).toBe(`${second.pathDir}:/usr/bin`)
+    expect(readFileSync(unknownExecutable, 'utf8')).toBe('locked or foreign')
     expect(readFileSync(target, 'utf8')).toBe('outside')
-    expect(environment).toEqual({ PATH: '/usr/bin' })
+    second.dispose()
   })
 
-  it('recovers from stray command files instead of failing startup', () => {
+  it('leaves legacy unknown files untouched and excludes their directories from PATH', () => {
     const root = temporaryDirectory()
     const stateDir = join(root, 'runtime')
-    const pathDir = join(stateDir, 'bin')
-    const nodeBinDir = join(stateDir, 'private', 'node-bin')
-    mkdirSync(pathDir, { recursive: true })
-    mkdirSync(nodeBinDir, { recursive: true })
-    writeFileSync(join(pathDir, 'dsh'), 'stray')
-    writeFileSync(join(nodeBinDir, 'dsh'), 'stray')
-    const environment: NodeJS.ProcessEnv = { PATH: '/usr/bin' }
-    const stderr = vi.spyOn(process.stderr, 'write').mockImplementation(() => true)
+    const legacyPathDir = join(stateDir, 'bin')
+    const legacyNodeBinDir = join(stateDir, 'private', 'node-bin')
+    mkdirSync(legacyPathDir, { recursive: true })
+    mkdirSync(legacyNodeBinDir, { recursive: true })
+    const publicUnknown = join(legacyPathDir, 'bsk.exe')
+    const privateUnknown = join(legacyNodeBinDir, 'bsk.exe')
+    writeFileSync(publicUnknown, 'locked public command')
+    writeFileSync(privateUnknown, 'locked private command')
+    const environment: NodeJS.ProcessEnv = {
+      PATH: `${legacyPathDir}:${legacyNodeBinDir}:/usr/bin`,
+    }
 
     const installation = installDesktopPnpmRuntime(options(stateDir, 'linux', environment))
 
-    expect(readdirSync(pathDir)).toEqual(['pnpm'])
-    expect(readdirSync(nodeBinDir)).toEqual(['node'])
-    expect(environment.PATH).toBe(`${pathDir}:/usr/bin`)
-    expect(stderr).toHaveBeenCalledTimes(2)
+    expect(installation.pathDir).not.toBe(legacyPathDir)
+    expect(environment.PATH).toBe(`${installation.pathDir}:/usr/bin`)
+    expect(readFileSync(publicUnknown, 'utf8')).toBe('locked public command')
+    expect(readFileSync(privateUnknown, 'utf8')).toBe('locked private command')
     installation.dispose()
   })
 
-  it('removes stray symlinks without touching their targets', () => {
+  it('does not attempt to delete a published generation that could still be locked', () => {
     const root = temporaryDirectory()
     const stateDir = join(root, 'runtime')
-    const pathDir = join(stateDir, 'bin')
-    mkdirSync(pathDir, { recursive: true })
-    const target = join(root, 'outside')
-    writeFileSync(target, 'outside')
-    symlinkSync(target, join(pathDir, 'dsh'))
-    const stderr = vi.spyOn(process.stderr, 'write').mockImplementation(() => true)
-
-    const installation = installDesktopPnpmRuntime(options(stateDir, 'linux', { PATH: '/usr/bin' }))
-
-    expect(readdirSync(pathDir)).toEqual(['pnpm'])
-    expect(readFileSync(target, 'utf8')).toBe('outside')
-    expect(stderr).toHaveBeenCalledOnce()
-    installation.dispose()
-  })
-
-  it('refuses an unexpected directory in the public command directory', () => {
-    const root = temporaryDirectory()
-    const stateDir = join(root, 'runtime')
-    const pathDir = join(stateDir, 'bin')
-    mkdirSync(join(pathDir, 'dsh'), { recursive: true })
     const environment: NodeJS.ProcessEnv = { PATH: '/usr/bin' }
+    const first = installDesktopPnpmRuntime(options(stateDir, 'linux', environment))
+    const firstRoot = dirname(first.pathDir)
+    first.dispose()
+    const originalRmSync = fs.rmSync
+    const rm = vi.spyOn(fs, 'rmSync').mockImplementation((filename, rmOptions) => {
+      if (filename === firstRoot) {
+        throw Object.assign(new Error('locked'), { code: 'EPERM' })
+      }
+      return originalRmSync(filename, rmOptions)
+    })
+    syncBuiltinESMExports()
 
-    expect(() => installDesktopPnpmRuntime(options(stateDir, 'linux', environment)))
-      .toThrow('contains an unexpected directory: dsh')
-    expect(environment).toEqual({ PATH: '/usr/bin' })
-  })
+    let second: ReturnType<typeof installDesktopPnpmRuntime> | undefined
+    try {
+      second = installDesktopPnpmRuntime({
+        ...options(stateDir, 'linux', environment),
+        electronVersion: '44.0.0',
+      })
+    } finally {
+      rm.mockRestore()
+      syncBuiltinESMExports()
+    }
 
-  it('removes only strictly named stale atomic files before validating commands', () => {
-    const root = temporaryDirectory()
-    const stateDir = join(root, 'runtime')
-    const pathDir = join(stateDir, 'bin')
-    mkdirSync(pathDir, { recursive: true })
-    const stale = join(pathDir, '.pnpm.123.123e4567-e89b-12d3-a456-426614174000.tmp')
-    writeFileSync(stale, 'partial')
-    const environment: NodeJS.ProcessEnv = { PATH: '/usr/bin' }
-
-    const installation = installDesktopPnpmRuntime(options(stateDir, 'linux', environment))
-
-    expect(readdirSync(pathDir)).toEqual(['pnpm'])
-    installation.dispose()
+    expect(second).toBeDefined()
+    expect(environment.PATH).toBe(`${second?.pathDir}:/usr/bin`)
+    expect(existsSync(firstRoot)).toBe(true)
+    expect(rm.mock.calls.some(([filename]) => filename === firstRoot)).toBe(false)
+    second?.dispose()
   })
 
   it('fails loud for unsupported platforms and unsafe generated values', () => {
@@ -429,6 +465,32 @@ describe('desktop Host pnpm runtime', () => {
 })
 
 describe('desktop Host dsh runtime', () => {
+  it('content-addresses Windows DSH shims and reuses an exact generation', () => {
+    const root = temporaryDirectory()
+    const stateDir = join(root, 'runtime')
+    const environment: NodeJS.ProcessEnv = { Path: 'C:\\Windows' }
+    const runtimeOptions = {
+      platform: 'win32' as const,
+      appExecutable: 'C:\\Program Files\\DSH Desktop\\DSH Desktop.exe',
+      dshBootstrapPath: 'C:\\Program Files\\DSH Desktop\\resources\\app.asar\\desktop-cli.js',
+      profileName: 'web',
+      homeDir: 'C:\\Users\\tester\\.dsh',
+      stateDir,
+      environment,
+    }
+
+    const first = installDesktopDshRuntime(runtimeOptions)
+    const firstRoot = dirname(first.pathDir)
+    first.dispose()
+    const second = installDesktopDshRuntime(runtimeOptions)
+
+    expect(second.pathDir).toBe(first.pathDir)
+    expect(readdirSync(second.pathDir)).toEqual(['dsh.cmd'])
+    expect(readdirSync(firstRoot).sort()).toEqual(['.generation.json', 'bin'])
+    expect(readFileSync(second.dshShimPath, 'utf8')).toContain('set "DSH_DESKTOP_DEFAULT_PROFILE=web"')
+    second.dispose()
+  })
+
   it.runIf(process.platform === 'win32')('makes the active profile available to Host plugin child processes', () => {
     const root = temporaryDirectory()
     const stateDir = join(root, 'runtime')