diff --git a/src/main/git/worktree-shared-directories.test.ts b/src/main/git/worktree-shared-directories.test.ts
index 7bd33987fba..21c6926c7b3 100644
--- a/src/main/git/worktree-shared-directories.test.ts
+++ b/src/main/git/worktree-shared-directories.test.ts
@@ -6,6 +6,8 @@ import { afterAll, afterEach, beforeAll, beforeEach, describe, expect, it, vi }
 import {
   clearConfiguredWorktreeSharedDirectoriesCacheForTests,
   getConfiguredWorktreeSharedDirectories,
+  getConfiguredWorktreeSharedDirectoriesCacheSizeForTests,
+  MAX_CONFIGURED_SHARED_DIRECTORIES_CACHE_ENTRIES,
   getWorktreeSharedLinkPaths,
   resolveWorktreeSharedDirectories
 } from './worktree-shared-directories'
@@ -175,6 +177,15 @@ describe('resolveWorktreeSharedDirectories', () => {
 })
 
 describe('getConfiguredWorktreeSharedDirectories', () => {
+  it('bounds cache growth when repository paths churn', () => {
+    for (let index = 0; index < MAX_CONFIGURED_SHARED_DIRECTORIES_CACHE_ENTRIES + 4; index += 1) {
+      getConfiguredWorktreeSharedDirectories(`/repo-${index}`)
+    }
+
+    expect(getConfiguredWorktreeSharedDirectoriesCacheSizeForTests()).toBe(
+      MAX_CONFIGURED_SHARED_DIRECTORIES_CACHE_ENTRIES
+    )
+  })
   let repo: string
 
   beforeEach(() => {
diff --git a/src/main/git/worktree-shared-directories.ts b/src/main/git/worktree-shared-directories.ts
index 1dfe990a0e6..5d633d89c88 100644
--- a/src/main/git/worktree-shared-directories.ts
+++ b/src/main/git/worktree-shared-directories.ts
@@ -10,6 +10,7 @@ import { mapWithConcurrency } from '../../shared/map-with-concurrency'
 // duplicates disk; `orca.yaml` names the ones every worktree should share instead.
 
 const CONFIGURED_SHARED_DIRECTORIES_CACHE_TTL_MS = 30_000
+export const MAX_CONFIGURED_SHARED_DIRECTORIES_CACHE_ENTRIES = 512
 // Why: resolving a worktree may list many generated directories; overlap
 // independent local probes without flooding the filesystem threadpool.
 const SHARED_DIRECTORY_STAT_CONCURRENCY = 8
@@ -33,6 +34,8 @@ export function getConfiguredWorktreeSharedDirectories(repoPath: string): readon
   const cached = configuredSharedDirectoriesByRepoPath.get(repoPath)
   const now = Date.now()
   if (cached && cached.expiresAt > now) {
+    configuredSharedDirectoriesByRepoPath.delete(repoPath)
+    configuredSharedDirectoriesByRepoPath.set(repoPath, cached)
     return cached.directories
   }
   const configured = loadHooks(repoPath)?.worktree?.sharedDirectories ?? []
@@ -40,6 +43,15 @@ export function getConfiguredWorktreeSharedDirectories(repoPath: string): readon
     directories: configured,
     expiresAt: now + CONFIGURED_SHARED_DIRECTORIES_CACHE_TTL_MS
   })
+  while (
+    configuredSharedDirectoriesByRepoPath.size > MAX_CONFIGURED_SHARED_DIRECTORIES_CACHE_ENTRIES
+  ) {
+    const oldest = configuredSharedDirectoriesByRepoPath.keys().next()
+    if (oldest.done || oldest.value === repoPath) {
+      break
+    }
+    configuredSharedDirectoriesByRepoPath.delete(oldest.value)
+  }
   return configured
 }
 
@@ -48,6 +60,10 @@ export function clearConfiguredWorktreeSharedDirectoriesCacheForTests(): void {
   configuredSharedDirectoriesByRepoPath.clear()
 }
 
+export function getConfiguredWorktreeSharedDirectoriesCacheSizeForTests(): number {
+  return configuredSharedDirectoriesByRepoPath.size
+}
+
 /** Every path Orca may have symlinked into a worktree: the per-user Worktree
  *  Shared Paths setting plus the repo's `orca.yaml` shared directories.
  *