diff --git a/packages/cli/src/ui/hooks/useAtCompletion.test.ts b/packages/cli/src/ui/hooks/useAtCompletion.test.ts
index 599f8fdf..b7ce4470 100644
--- a/packages/cli/src/ui/hooks/useAtCompletion.test.ts
+++ b/packages/cli/src/ui/hooks/useAtCompletion.test.ts
@@ -9,7 +9,7 @@
 import { describe, it, expect, beforeEach, vi, afterEach } from 'vitest';
 import { renderHook, waitFor, act } from '@testing-library/react';
 import { useAtCompletion } from './useAtCompletion.js';
-import { Config, FileSearch } from '@google/gemini-cli-core';
+import { Config, FileSearch, FileSearchFactory } from '@google/gemini-cli-core';
 import {
   createTmpDir,
   cleanupTmpDir,
@@ -190,14 +190,25 @@ describe('useAtCompletion', () => {
       const structure: FileSystemStructure = { 'a.txt': '', 'b.txt': '' };
       testRootDir = await createTmpDir(structure);
 
-      // Spy on the search method to introduce an artificial delay
-      const originalSearch = FileSearch.prototype.search;
-      vi.spyOn(FileSearch.prototype, 'search').mockImplementation(
-        async function (...args) {
+      const realFileSearch = FileSearchFactory.create({
+        projectRoot: testRootDir,
+        ignoreDirs: [],
+        useGitignore: true,
+        useGeminiignore: true,
+        cache: false,
+        cacheTtl: 0,
+        enableRecursiveFileSearch: true,
+      });
+      await realFileSearch.initialize();
+
+      const mockFileSearch: FileSearch = {
+        initialize: vi.fn().mockResolvedValue(undefined),
+        search: vi.fn().mockImplementation(async (...args) => {
           await new Promise((resolve) => setTimeout(resolve, 300));
-          return originalSearch.apply(this, args);
-        },
-      );
+          return realFileSearch.search(...args);
+        }),
+      };
+      vi.spyOn(FileSearchFactory, 'create').mockReturnValue(mockFileSearch);
 
       const { result, rerender } = renderHook(
         ({ pattern }) =>
@@ -241,14 +252,15 @@ describe('useAtCompletion', () => {
       testRootDir = await createTmpDir(structure);
 
       const abortSpy = vi.spyOn(AbortController.prototype, 'abort');
-      const searchSpy = vi
-        .spyOn(FileSearch.prototype, 'search')
-        .mockImplementation(async (...args) => {
-          const delay = args[0] === 'a' ? 500 : 50;
+      const mockFileSearch: FileSearch = {
+        initialize: vi.fn().mockResolvedValue(undefined),
+        search: vi.fn().mockImplementation(async (pattern: string) => {
+          const delay = pattern === 'a' ? 500 : 50;
           await new Promise((resolve) => setTimeout(resolve, delay));
-          // eslint-disable-next-line @typescript-eslint/no-explicit-any
-          return [args[0] as any];
-        });
+          return [pattern];
+        }),
+      };
+      vi.spyOn(FileSearchFactory, 'create').mockReturnValue(mockFileSearch);
 
       const { result, rerender } = renderHook(
         ({ pattern }) =>
@@ -258,7 +270,10 @@ describe('useAtCompletion', () => {
 
       // Wait for the hook to be ready (initialization is complete)
       await waitFor(() => {
-        expect(searchSpy).toHaveBeenCalledWith('a', expect.any(Object));
+        expect(mockFileSearch.search).toHaveBeenCalledWith(
+          'a',
+          expect.any(Object),
+        );
       });
 
       // Now that the first search is in-flight, trigger the second one.
@@ -278,9 +293,10 @@ describe('useAtCompletion', () => {
       );
 
       // The search spy should have been called for both patterns.
-      expect(searchSpy).toHaveBeenCalledWith('b', expect.any(Object));
-
-      vi.restoreAllMocks();
+      expect(mockFileSearch.search).toHaveBeenCalledWith(
+        'b',
+        expect.any(Object),
+      );
     });
   });
 
@@ -313,9 +329,13 @@ describe('useAtCompletion', () => {
       testRootDir = await createTmpDir({});
 
       // Force an error during initialization
-      vi.spyOn(FileSearch.prototype, 'initialize').mockRejectedValueOnce(
-        new Error('Initialization failed'),
-      );
+      const mockFileSearch: FileSearch = {
+        initialize: vi
+          .fn()
+          .mockRejectedValue(new Error('Initialization failed')),
+        search: vi.fn(),
+      };
+      vi.spyOn(FileSearchFactory, 'create').mockReturnValue(mockFileSearch);
 
       const { result, rerender } = renderHook(
         ({ enabled }) =>
diff --git a/packages/cli/src/ui/hooks/useAtCompletion.ts b/packages/cli/src/ui/hooks/useAtCompletion.ts
index f6835dc8..5a2571a0 100644
--- a/packages/cli/src/ui/hooks/useAtCompletion.ts
+++ b/packages/cli/src/ui/hooks/useAtCompletion.ts
@@ -5,7 +5,12 @@
  */
 
 import { useEffect, useReducer, useRef } from 'react';
-import { Config, FileSearch, escapePath } from '@google/gemini-cli-core';
+import {
+  Config,
+  FileSearch,
+  FileSearchFactory,
+  escapePath,
+} from '@google/gemini-cli-core';
 import {
   Suggestion,
   MAX_SUGGESTIONS_TO_SHOW,
@@ -156,7 +161,7 @@ export function useAtCompletion(props: UseAtCompletionProps): void {
   useEffect(() => {
     const initialize = async () => {
       try {
-        const searcher = new FileSearch({
+        const searcher = FileSearchFactory.create({
           projectRoot: cwd,
           ignoreDirs: [],
           useGitignore:
@@ -165,9 +170,8 @@ export function useAtCompletion(props: UseAtCompletionProps): void {
             config?.getFileFilteringOptions()?.respectGeminiIgnore ?? true,
           cache: true,
           cacheTtl: 30, // 30 seconds
-          maxDepth: !(config?.getEnableRecursiveFileSearch() ?? true)
-            ? 0
-            : undefined,
+          enableRecursiveFileSearch:
+            config?.getEnableRecursiveFileSearch() ?? true,
         });
         await searcher.initialize();
         fileSearch.current = searcher;
diff --git a/packages/core/src/utils/filesearch/crawler.test.ts b/packages/core/src/utils/filesearch/crawler.test.ts
new file mode 100644
index 00000000..baa4d19a
--- /dev/null
+++ b/packages/core/src/utils/filesearch/crawler.test.ts
@@ -0,0 +1,573 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, it, expect, afterEach, vi, beforeEach } from 'vitest';
+import * as fs from 'fs/promises';
+import * as path from 'path';
+import * as cache from './crawlCache.js';
+import { crawl } from './crawler.js';
+import { createTmpDir, cleanupTmpDir } from '@google/gemini-cli-test-utils';
+import { Ignore, loadIgnoreRules } from './ignore.js';
+
+describe('crawler', () => {
+  let tmpDir: string;
+  afterEach(async () => {
+    if (tmpDir) {
+      await cleanupTmpDir(tmpDir);
+    }
+    vi.restoreAllMocks();
+  });
+
+  it('should use .geminiignore rules', async () => {
+    tmpDir = await createTmpDir({
+      '.geminiignore': 'dist/',
+      dist: ['ignored.js'],
+      src: ['not-ignored.js'],
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: false,
+      useGeminiignore: true,
+      ignoreDirs: [],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+
+    expect(results).toEqual(
+      expect.arrayContaining([
+        '.',
+        'src/',
+        '.geminiignore',
+        'src/not-ignored.js',
+      ]),
+    );
+  });
+
+  it('should combine .gitignore and .geminiignore rules', async () => {
+    tmpDir = await createTmpDir({
+      '.gitignore': 'dist/',
+      '.geminiignore': 'build/',
+      dist: ['ignored-by-git.js'],
+      build: ['ignored-by-gemini.js'],
+      src: ['not-ignored.js'],
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: true,
+      ignoreDirs: [],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+
+    expect(results).toEqual(
+      expect.arrayContaining([
+        '.',
+        'src/',
+        '.geminiignore',
+        '.gitignore',
+        'src/not-ignored.js',
+      ]),
+    );
+  });
+
+  it('should use ignoreDirs option', async () => {
+    tmpDir = await createTmpDir({
+      logs: ['some.log'],
+      src: ['main.js'],
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: false,
+      useGeminiignore: false,
+      ignoreDirs: ['logs'],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+
+    expect(results).toEqual(
+      expect.arrayContaining(['.', 'src/', 'src/main.js']),
+    );
+  });
+
+  it('should handle negated directories', async () => {
+    tmpDir = await createTmpDir({
+      '.gitignore': ['build/**', '!build/public', '!build/public/**'].join(
+        '\n',
+      ),
+      build: {
+        'private.js': '',
+        public: ['index.html'],
+      },
+      src: ['main.js'],
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: false,
+      ignoreDirs: [],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+
+    expect(results).toEqual(
+      expect.arrayContaining([
+        '.',
+        'build/',
+        'build/public/',
+        'src/',
+        '.gitignore',
+        'build/public/index.html',
+        'src/main.js',
+      ]),
+    );
+  });
+
+  it('should handle root-level file negation', async () => {
+    tmpDir = await createTmpDir({
+      '.gitignore': ['*.mk', '!Foo.mk'].join('\n'),
+      'bar.mk': '',
+      'Foo.mk': '',
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: false,
+      ignoreDirs: [],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+
+    expect(results).toEqual(
+      expect.arrayContaining(['.', '.gitignore', 'Foo.mk', 'bar.mk']),
+    );
+  });
+
+  it('should handle directory negation with glob', async () => {
+    tmpDir = await createTmpDir({
+      '.gitignore': [
+        'third_party/**',
+        '!third_party/foo',
+        '!third_party/foo/bar',
+        '!third_party/foo/bar/baz_buffer',
+      ].join('\n'),
+      third_party: {
+        foo: {
+          bar: {
+            baz_buffer: '',
+          },
+        },
+        ignore_this: '',
+      },
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: false,
+      ignoreDirs: [],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+
+    expect(results).toEqual(
+      expect.arrayContaining([
+        '.',
+        'third_party/',
+        'third_party/foo/',
+        'third_party/foo/bar/',
+        '.gitignore',
+        'third_party/foo/bar/baz_buffer',
+      ]),
+    );
+  });
+
+  it('should correctly handle negated patterns in .gitignore', async () => {
+    tmpDir = await createTmpDir({
+      '.gitignore': ['dist/**', '!dist/keep.js'].join('\n'),
+      dist: ['ignore.js', 'keep.js'],
+      src: ['main.js'],
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: false,
+      ignoreDirs: [],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+
+    expect(results).toEqual(
+      expect.arrayContaining([
+        '.',
+        'dist/',
+        'src/',
+        '.gitignore',
+        'dist/keep.js',
+        'src/main.js',
+      ]),
+    );
+  });
+
+  it('should initialize correctly when ignore files are missing', async () => {
+    tmpDir = await createTmpDir({
+      src: ['file1.js'],
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: true,
+      ignoreDirs: [],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+    expect(results).toEqual(
+      expect.arrayContaining(['.', 'src/', 'src/file1.js']),
+    );
+  });
+
+  it('should handle empty or commented-only ignore files', async () => {
+    tmpDir = await createTmpDir({
+      '.gitignore': '# This is a comment\n\n   \n',
+      src: ['main.js'],
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: false,
+      ignoreDirs: [],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+
+    expect(results).toEqual(
+      expect.arrayContaining(['.', 'src/', '.gitignore', 'src/main.js']),
+    );
+  });
+
+  it('should always ignore the .git directory', async () => {
+    tmpDir = await createTmpDir({
+      '.git': ['config', 'HEAD'],
+      src: ['main.js'],
+    });
+
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: false,
+      useGeminiignore: false,
+      ignoreDirs: [],
+    });
+
+    const results = await crawl({
+      crawlDirectory: tmpDir,
+      cwd: tmpDir,
+      ignore,
+      cache: false,
+      cacheTtl: 0,
+    });
+
+    expect(results).toEqual(
+      expect.arrayContaining(['.', 'src/', 'src/main.js']),
+    );
+  });
+
+  describe('with in-memory cache', () => {
+    beforeEach(() => {
+      cache.clear();
+      vi.useFakeTimers();
+    });
+
+    afterEach(() => {
+      vi.useRealTimers();
+    });
+
+    it('should hit the cache for subsequent crawls', async () => {
+      tmpDir = await createTmpDir({ 'file1.js': '' });
+      const ignore = loadIgnoreRules({
+        projectRoot: tmpDir,
+        useGitignore: false,
+        useGeminiignore: false,
+        ignoreDirs: [],
+      });
+      const options = {
+        crawlDirectory: tmpDir,
+        cwd: tmpDir,
+        ignore,
+        cache: true,
+        cacheTtl: 10,
+      };
+
+      const crawlSpy = vi.spyOn(cache, 'read');
+
+      await crawl(options);
+      expect(crawlSpy).toHaveBeenCalledTimes(1);
+
+      await crawl(options);
+      expect(crawlSpy).toHaveBeenCalledTimes(2);
+      // fdir should not have been called a second time.
+      // We can't spy on it directly, but we can check the cache was hit.
+      const cacheKey = cache.getCacheKey(
+        options.crawlDirectory,
+        options.ignore.getFingerprint(),
+        undefined,
+      );
+      expect(cache.read(cacheKey)).toBeDefined();
+    });
+
+    it('should miss the cache when ignore rules change', async () => {
+      tmpDir = await createTmpDir({
+        '.gitignore': 'a.txt',
+        'a.txt': '',
+        'b.txt': '',
+      });
+      const getIgnore = () =>
+        loadIgnoreRules({
+          projectRoot: tmpDir,
+          useGitignore: true,
+          useGeminiignore: false,
+          ignoreDirs: [],
+        });
+      const getOptions = (ignore: Ignore) => ({
+        crawlDirectory: tmpDir,
+        cwd: tmpDir,
+        ignore,
+        cache: true,
+        cacheTtl: 10000,
+      });
+
+      // Initial crawl to populate the cache
+      const ignore1 = getIgnore();
+      const results1 = await crawl(getOptions(ignore1));
+      expect(results1).toEqual(
+        expect.arrayContaining(['.', '.gitignore', 'b.txt']),
+      );
+
+      // Modify the ignore file
+      await fs.writeFile(path.join(tmpDir, '.gitignore'), 'b.txt');
+
+      // Second crawl should miss the cache and trigger a recrawl
+      const ignore2 = getIgnore();
+      const results2 = await crawl(getOptions(ignore2));
+      expect(results2).toEqual(
+        expect.arrayContaining(['.', '.gitignore', 'a.txt']),
+      );
+    });
+
+    it('should miss the cache after TTL expires', async () => {
+      tmpDir = await createTmpDir({ 'file1.js': '' });
+      const ignore = loadIgnoreRules({
+        projectRoot: tmpDir,
+        useGitignore: false,
+        useGeminiignore: false,
+        ignoreDirs: [],
+      });
+      const options = {
+        crawlDirectory: tmpDir,
+        cwd: tmpDir,
+        ignore,
+        cache: true,
+        cacheTtl: 10, // 10 seconds
+      };
+
+      const readSpy = vi.spyOn(cache, 'read');
+      const writeSpy = vi.spyOn(cache, 'write');
+
+      await crawl(options);
+      expect(readSpy).toHaveBeenCalledTimes(1);
+      expect(writeSpy).toHaveBeenCalledTimes(1);
+
+      // Advance time past the TTL
+      await vi.advanceTimersByTimeAsync(11000);
+
+      await crawl(options);
+      expect(readSpy).toHaveBeenCalledTimes(2);
+      expect(writeSpy).toHaveBeenCalledTimes(2);
+    });
+
+    it('should miss the cache when maxDepth changes', async () => {
+      tmpDir = await createTmpDir({ 'file1.js': '' });
+      const ignore = loadIgnoreRules({
+        projectRoot: tmpDir,
+        useGitignore: false,
+        useGeminiignore: false,
+        ignoreDirs: [],
+      });
+      const getOptions = (maxDepth?: number) => ({
+        crawlDirectory: tmpDir,
+        cwd: tmpDir,
+        ignore,
+        cache: true,
+        cacheTtl: 10000,
+        maxDepth,
+      });
+
+      const readSpy = vi.spyOn(cache, 'read');
+      const writeSpy = vi.spyOn(cache, 'write');
+
+      // 1. First crawl with maxDepth: 1
+      await crawl(getOptions(1));
+      expect(readSpy).toHaveBeenCalledTimes(1);
+      expect(writeSpy).toHaveBeenCalledTimes(1);
+
+      // 2. Second crawl with maxDepth: 2, should be a cache miss
+      await crawl(getOptions(2));
+      expect(readSpy).toHaveBeenCalledTimes(2);
+      expect(writeSpy).toHaveBeenCalledTimes(2);
+
+      // 3. Third crawl with maxDepth: 1 again, should be a cache hit.
+      await crawl(getOptions(1));
+      expect(readSpy).toHaveBeenCalledTimes(3);
+      expect(writeSpy).toHaveBeenCalledTimes(2); // No new write
+    });
+  });
+
+  describe('with maxDepth', () => {
+    beforeEach(async () => {
+      tmpDir = await createTmpDir({
+        'file-root.txt': '',
+        level1: {
+          'file-level1.txt': '',
+          level2: {
+            'file-level2.txt': '',
+            level3: {
+              'file-level3.txt': '',
+            },
+          },
+        },
+      });
+    });
+
+    const getCrawlResults = (maxDepth?: number) => {
+      const ignore = loadIgnoreRules({
+        projectRoot: tmpDir,
+        useGitignore: false,
+        useGeminiignore: false,
+        ignoreDirs: [],
+      });
+      return crawl({
+        crawlDirectory: tmpDir,
+        cwd: tmpDir,
+        ignore,
+        cache: false,
+        cacheTtl: 0,
+        maxDepth,
+      });
+    };
+
+    it('should only crawl top-level files when maxDepth is 0', async () => {
+      const results = await getCrawlResults(0);
+      expect(results).toEqual(
+        expect.arrayContaining(['.', 'level1/', 'file-root.txt']),
+      );
+    });
+
+    it('should crawl one level deep when maxDepth is 1', async () => {
+      const results = await getCrawlResults(1);
+      expect(results).toEqual(
+        expect.arrayContaining([
+          '.',
+          'level1/',
+          'level1/level2/',
+          'file-root.txt',
+          'level1/file-level1.txt',
+        ]),
+      );
+    });
+
+    it('should crawl two levels deep when maxDepth is 2', async () => {
+      const results = await getCrawlResults(2);
+      expect(results).toEqual(
+        expect.arrayContaining([
+          '.',
+          'level1/',
+          'level1/level2/',
+          'level1/level2/level3/',
+          'file-root.txt',
+          'level1/file-level1.txt',
+          'level1/level2/file-level2.txt',
+        ]),
+      );
+    });
+
+    it('should perform a full recursive crawl when maxDepth is undefined', async () => {
+      const results = await getCrawlResults(undefined);
+      expect(results).toEqual(
+        expect.arrayContaining([
+          '.',
+          'level1/',
+          'level1/level2/',
+          'level1/level2/level3/',
+          'file-root.txt',
+          'level1/file-level1.txt',
+          'level1/level2/file-level2.txt',
+          'level1/level2/level3/file-level3.txt',
+        ]),
+      );
+    });
+  });
+});
diff --git a/packages/core/src/utils/filesearch/crawler.ts b/packages/core/src/utils/filesearch/crawler.ts
new file mode 100644
index 00000000..7e422b06
--- /dev/null
+++ b/packages/core/src/utils/filesearch/crawler.ts
@@ -0,0 +1,85 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import path from 'node:path';
+import { fdir } from 'fdir';
+import { Ignore } from './ignore.js';
+import * as cache from './crawlCache.js';
+
+export interface CrawlOptions {
+  // The directory to start the crawl from.
+  crawlDirectory: string;
+  // The project's root directory, for path relativity.
+  cwd: string;
+  // The fdir maxDepth option.
+  maxDepth?: number;
+  // A pre-configured Ignore instance.
+  ignore: Ignore;
+  // Caching options.
+  cache: boolean;
+  cacheTtl: number;
+}
+
+function toPosixPath(p: string) {
+  return p.split(path.sep).join(path.posix.sep);
+}
+
+export async function crawl(options: CrawlOptions): Promise<string[]> {
+  if (options.cache) {
+    const cacheKey = cache.getCacheKey(
+      options.crawlDirectory,
+      options.ignore.getFingerprint(),
+      options.maxDepth,
+    );
+    const cachedResults = cache.read(cacheKey);
+
+    if (cachedResults) {
+      return cachedResults;
+    }
+  }
+
+  const posixCwd = toPosixPath(options.cwd);
+  const posixCrawlDirectory = toPosixPath(options.crawlDirectory);
+
+  let results: string[];
+  try {
+    const dirFilter = options.ignore.getDirectoryFilter();
+    const api = new fdir()
+      .withRelativePaths()
+      .withDirs()
+      .withPathSeparator('/') // Always use unix style paths
+      .exclude((_, dirPath) => {
+        const relativePath = path.posix.relative(posixCrawlDirectory, dirPath);
+        return dirFilter(`${relativePath}/`);
+      });
+
+    if (options.maxDepth !== undefined) {
+      api.withMaxDepth(options.maxDepth);
+    }
+
+    results = await api.crawl(options.crawlDirectory).withPromise();
+  } catch (_e) {
+    // The directory probably doesn't exist.
+    return [];
+  }
+
+  const relativeToCrawlDir = path.posix.relative(posixCwd, posixCrawlDirectory);
+
+  const relativeToCwdResults = results.map((p) =>
+    path.posix.join(relativeToCrawlDir, p),
+  );
+
+  if (options.cache) {
+    const cacheKey = cache.getCacheKey(
+      options.crawlDirectory,
+      options.ignore.getFingerprint(),
+      options.maxDepth,
+    );
+    cache.write(cacheKey, relativeToCwdResults, options.cacheTtl * 1000);
+  }
+
+  return relativeToCwdResults;
+}
diff --git a/packages/core/src/utils/filesearch/fileSearch.test.ts b/packages/core/src/utils/filesearch/fileSearch.test.ts
index 38657492..2deea82d 100644
--- a/packages/core/src/utils/filesearch/fileSearch.test.ts
+++ b/packages/core/src/utils/filesearch/fileSearch.test.ts
@@ -4,17 +4,10 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
-import * as fs from 'fs/promises';
-import * as path from 'path';
-import * as cache from './crawlCache.js';
-import { FileSearch, AbortError, filter } from './fileSearch.js';
+import { describe, it, expect, afterEach, vi } from 'vitest';
+import { FileSearchFactory, AbortError, filter } from './fileSearch.js';
 import { createTmpDir, cleanupTmpDir } from '@google/gemini-cli-test-utils';
 
-type FileSearchWithPrivateMethods = FileSearch & {
-  performCrawl: () => Promise<void>;
-};
-
 describe('FileSearch', () => {
   let tmpDir: string;
   afterEach(async () => {
@@ -31,13 +24,14 @@ describe('FileSearch', () => {
       src: ['not-ignored.js'],
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: true,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -55,13 +49,14 @@ describe('FileSearch', () => {
       src: ['not-ignored.js'],
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: true,
       useGeminiignore: true,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -81,13 +76,14 @@ describe('FileSearch', () => {
       src: ['main.js'],
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: false,
       ignoreDirs: ['logs'],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -108,13 +104,14 @@ describe('FileSearch', () => {
       src: ['main.js'],
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: true,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -139,13 +136,14 @@ describe('FileSearch', () => {
       },
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -161,13 +159,14 @@ describe('FileSearch', () => {
       'Foo.mk': '',
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: true,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -194,13 +193,14 @@ describe('FileSearch', () => {
       },
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: true,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -222,13 +222,14 @@ describe('FileSearch', () => {
       src: ['main.js'],
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: true,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -250,13 +251,14 @@ describe('FileSearch', () => {
       src: ['file1.js'],
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: true,
       useGeminiignore: true,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     // Expect no errors to be thrown during initialization
@@ -275,13 +277,14 @@ describe('FileSearch', () => {
       },
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -299,13 +302,14 @@ describe('FileSearch', () => {
       },
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -319,13 +323,14 @@ describe('FileSearch', () => {
       src: ['file1.js'],
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -346,170 +351,21 @@ describe('FileSearch', () => {
     await expect(filterPromise).rejects.toThrow(AbortError);
   });
 
-  describe('with in-memory cache', () => {
-    beforeEach(() => {
-      cache.clear();
+  it('should throw an error if search is called before initialization', async () => {
+    tmpDir = await createTmpDir({});
+    const fileSearch = FileSearchFactory.create({
+      projectRoot: tmpDir,
+      useGitignore: false,
+      useGeminiignore: false,
+      ignoreDirs: [],
+      cache: false,
+      cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
-    afterEach(() => {
-      vi.useRealTimers();
-    });
-
-    it('should throw an error if search is called before initialization', async () => {
-      tmpDir = await createTmpDir({});
-      const fileSearch = new FileSearch({
-        projectRoot: tmpDir,
-        useGitignore: false,
-        useGeminiignore: false,
-        ignoreDirs: [],
-        cache: false,
-        cacheTtl: 0,
-      });
-
-      await expect(fileSearch.search('')).rejects.toThrow(
-        'Engine not initialized. Call initialize() first.',
-      );
-    });
-
-    it('should hit the cache for subsequent searches', async () => {
-      tmpDir = await createTmpDir({ 'file1.js': '' });
-      const getOptions = () => ({
-        projectRoot: tmpDir,
-        useGitignore: false,
-        useGeminiignore: false,
-        ignoreDirs: [],
-        cache: true,
-        cacheTtl: 10,
-      });
-
-      const fs1 = new FileSearch(getOptions());
-      const crawlSpy1 = vi.spyOn(
-        fs1 as FileSearchWithPrivateMethods,
-        'performCrawl',
-      );
-      await fs1.initialize();
-      expect(crawlSpy1).toHaveBeenCalledTimes(1);
-
-      // Second search should hit the cache because the options are identical
-      const fs2 = new FileSearch(getOptions());
-      const crawlSpy2 = vi.spyOn(
-        fs2 as FileSearchWithPrivateMethods,
-        'performCrawl',
-      );
-      await fs2.initialize();
-      expect(crawlSpy2).not.toHaveBeenCalled();
-    });
-
-    it('should miss the cache when ignore rules change', async () => {
-      tmpDir = await createTmpDir({
-        '.gitignore': 'a.txt',
-        'a.txt': '',
-        'b.txt': '',
-      });
-      const options = {
-        projectRoot: tmpDir,
-        useGitignore: true,
-        useGeminiignore: false,
-        ignoreDirs: [],
-        cache: true,
-        cacheTtl: 10000,
-      };
-
-      // Initial search to populate the cache
-      const fs1 = new FileSearch(options);
-      const crawlSpy1 = vi.spyOn(
-        fs1 as FileSearchWithPrivateMethods,
-        'performCrawl',
-      );
-      await fs1.initialize();
-      const results1 = await fs1.search('');
-      expect(crawlSpy1).toHaveBeenCalledTimes(1);
-      expect(results1).toEqual(['.gitignore', 'b.txt']);
-
-      // Modify the ignore file
-      await fs.writeFile(path.join(tmpDir, '.gitignore'), 'b.txt');
-
-      // Second search should miss the cache and trigger a recrawl
-      const fs2 = new FileSearch(options);
-      const crawlSpy2 = vi.spyOn(
-        fs2 as FileSearchWithPrivateMethods,
-        'performCrawl',
-      );
-      await fs2.initialize();
-      const results2 = await fs2.search('');
-      expect(crawlSpy2).toHaveBeenCalledTimes(1);
-      expect(results2).toEqual(['.gitignore', 'a.txt']);
-    });
-
-    it('should miss the cache after TTL expires', async () => {
-      vi.useFakeTimers();
-      tmpDir = await createTmpDir({ 'file1.js': '' });
-      const options = {
-        projectRoot: tmpDir,
-        useGitignore: false,
-        useGeminiignore: false,
-        ignoreDirs: [],
-        cache: true,
-        cacheTtl: 10, // 10 seconds
-      };
-
-      // Initial search to populate the cache
-      const fs1 = new FileSearch(options);
-      await fs1.initialize();
-
-      // Advance time past the TTL
-      await vi.advanceTimersByTimeAsync(11000);
-
-      // Second search should miss the cache and trigger a recrawl
-      const fs2 = new FileSearch(options);
-      const crawlSpy = vi.spyOn(
-        fs2 as FileSearchWithPrivateMethods,
-        'performCrawl',
-      );
-      await fs2.initialize();
-
-      expect(crawlSpy).toHaveBeenCalledTimes(1);
-    });
-
-    it('should miss the cache when maxDepth changes', async () => {
-      tmpDir = await createTmpDir({ 'file1.js': '' });
-      const getOptions = (maxDepth?: number) => ({
-        projectRoot: tmpDir,
-        useGitignore: false,
-        useGeminiignore: false,
-        ignoreDirs: [],
-        cache: true,
-        cacheTtl: 10000,
-        maxDepth,
-      });
-
-      // 1. First search with maxDepth: 1, should trigger a crawl.
-      const fs1 = new FileSearch(getOptions(1));
-      const crawlSpy1 = vi.spyOn(
-        fs1 as FileSearchWithPrivateMethods,
-        'performCrawl',
-      );
-      await fs1.initialize();
-      expect(crawlSpy1).toHaveBeenCalledTimes(1);
-
-      // 2. Second search with maxDepth: 2, should be a cache miss and trigger a crawl.
-      const fs2 = new FileSearch(getOptions(2));
-      const crawlSpy2 = vi.spyOn(
-        fs2 as FileSearchWithPrivateMethods,
-        'performCrawl',
-      );
-      await fs2.initialize();
-      expect(crawlSpy2).toHaveBeenCalledTimes(1);
-
-      // 3. Third search with maxDepth: 1 again, should be a cache hit.
-      const fs3 = new FileSearch(getOptions(1));
-      const crawlSpy3 = vi.spyOn(
-        fs3 as FileSearchWithPrivateMethods,
-        'performCrawl',
-      );
-      await fs3.initialize();
-      expect(crawlSpy3).not.toHaveBeenCalled();
-    });
+    await expect(fileSearch.search('')).rejects.toThrow(
+      'Engine not initialized. Call initialize() first.',
+    );
   });
 
   it('should handle empty or commented-only ignore files', async () => {
@@ -518,13 +374,14 @@ describe('FileSearch', () => {
       src: ['main.js'],
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: true,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -539,13 +396,14 @@ describe('FileSearch', () => {
       src: ['main.js'],
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false, // Explicitly disable .gitignore to isolate this rule
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -561,13 +419,14 @@ describe('FileSearch', () => {
     }
     tmpDir = await createTmpDir(largeDir);
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -596,13 +455,14 @@ describe('FileSearch', () => {
       },
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: true, // Enable caching for this test
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -634,13 +494,14 @@ describe('FileSearch', () => {
       'other.txt': '',
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: false,
       cacheTtl: 0,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -676,13 +537,14 @@ describe('FileSearch', () => {
       'file5.js': '',
     });
 
-    const fileSearch = new FileSearch({
+    const fileSearch = FileSearchFactory.create({
       projectRoot: tmpDir,
       useGitignore: false,
       useGeminiignore: false,
       ignoreDirs: [],
       cache: true, // Ensure caching is enabled
       cacheTtl: 10000,
+      enableRecursiveFileSearch: true,
     });
 
     await fileSearch.initialize();
@@ -704,108 +566,97 @@ describe('FileSearch', () => {
     expect(limitedResults).toEqual(['file1.js', 'file2.js']);
   });
 
-  describe('with maxDepth', () => {
-    beforeEach(async () => {
+  describe('DirectoryFileSearch', () => {
+    it('should search for files in the current directory', async () => {
       tmpDir = await createTmpDir({
-        'file-root.txt': '',
-        level1: {
-          'file-level1.txt': '',
-          level2: {
-            'file-level2.txt': '',
-            level3: {
-              'file-level3.txt': '',
-            },
-          },
+        'file1.js': '',
+        'file2.ts': '',
+        'file3.js': '',
+      });
+
+      const fileSearch = FileSearchFactory.create({
+        projectRoot: tmpDir,
+        useGitignore: false,
+        useGeminiignore: false,
+        ignoreDirs: [],
+        cache: false,
+        cacheTtl: 0,
+        enableRecursiveFileSearch: false,
+      });
+
+      await fileSearch.initialize();
+      const results = await fileSearch.search('*.js');
+      expect(results).toEqual(['file1.js', 'file3.js']);
+    });
+
+    it('should search for files in a subdirectory', async () => {
+      tmpDir = await createTmpDir({
+        'file1.js': '',
+        src: {
+          'file2.js': '',
+          'file3.ts': '',
         },
       });
-    });
 
-    it('should only search top-level files when maxDepth is 0', async () => {
-      const fileSearch = new FileSearch({
+      const fileSearch = FileSearchFactory.create({
         projectRoot: tmpDir,
         useGitignore: false,
         useGeminiignore: false,
         ignoreDirs: [],
         cache: false,
         cacheTtl: 0,
-        maxDepth: 0,
+        enableRecursiveFileSearch: false,
       });
 
       await fileSearch.initialize();
-      const results = await fileSearch.search('');
-
-      expect(results).toEqual(['level1/', 'file-root.txt']);
+      const results = await fileSearch.search('src/*.js');
+      expect(results).toEqual(['src/file2.js']);
     });
 
-    it('should search one level deep when maxDepth is 1', async () => {
-      const fileSearch = new FileSearch({
+    it('should list all files in a directory', async () => {
+      tmpDir = await createTmpDir({
+        'file1.js': '',
+        src: {
+          'file2.js': '',
+          'file3.ts': '',
+        },
+      });
+
+      const fileSearch = FileSearchFactory.create({
         projectRoot: tmpDir,
         useGitignore: false,
         useGeminiignore: false,
         ignoreDirs: [],
         cache: false,
         cacheTtl: 0,
-        maxDepth: 1,
+        enableRecursiveFileSearch: false,
       });
 
       await fileSearch.initialize();
-      const results = await fileSearch.search('');
-
-      expect(results).toEqual([
-        'level1/',
-        'level1/level2/',
-        'file-root.txt',
-        'level1/file-level1.txt',
-      ]);
+      const results = await fileSearch.search('src/');
+      expect(results).toEqual(['src/file2.js', 'src/file3.ts']);
     });
 
-    it('should search two levels deep when maxDepth is 2', async () => {
-      const fileSearch = new FileSearch({
+    it('should respect ignore rules', async () => {
+      tmpDir = await createTmpDir({
+        '.gitignore': '*.js',
+        'file1.js': '',
+        'file2.ts': '',
+      });
+
+      const fileSearch = FileSearchFactory.create({
         projectRoot: tmpDir,
-        useGitignore: false,
+        useGitignore: true,
         useGeminiignore: false,
         ignoreDirs: [],
         cache: false,
         cacheTtl: 0,
-        maxDepth: 2,
+        enableRecursiveFileSearch: false,
       });
 
       await fileSearch.initialize();
-      const results = await fileSearch.search('');
-
-      expect(results).toEqual([
-        'level1/',
-        'level1/level2/',
-        'level1/level2/level3/',
-        'file-root.txt',
-        'level1/file-level1.txt',
-        'level1/level2/file-level2.txt',
-      ]);
-    });
-
-    it('should perform a full recursive search when maxDepth is undefined', async () => {
-      const fileSearch = new FileSearch({
-        projectRoot: tmpDir,
-        useGitignore: false,
-        useGeminiignore: false,
-        ignoreDirs: [],
-        cache: false,
-        cacheTtl: 0,
-        maxDepth: undefined, // Explicitly undefined
-      });
-
-      await fileSearch.initialize();
-      const results = await fileSearch.search('');
-
-      expect(results).toEqual([
-        'level1/',
-        'level1/level2/',
-        'level1/level2/level3/',
-        'file-root.txt',
-        'level1/file-level1.txt',
-        'level1/level2/file-level2.txt',
-        'level1/level2/level3/file-level3.txt',
-      ]);
+      const results = await fileSearch.search('*');
+      expect(results).toEqual(['.gitignore', 'file2.ts']);
     });
   });
 });
diff --git a/packages/core/src/utils/filesearch/fileSearch.ts b/packages/core/src/utils/filesearch/fileSearch.ts
index dff8d0ec..fa36dab4 100644
--- a/packages/core/src/utils/filesearch/fileSearch.ts
+++ b/packages/core/src/utils/filesearch/fileSearch.ts
@@ -5,23 +5,22 @@
  */
 
 import path from 'node:path';
-import fs from 'node:fs';
-import { fdir } from 'fdir';
 import picomatch from 'picomatch';
-import { Ignore } from './ignore.js';
+import { Ignore, loadIgnoreRules } from './ignore.js';
 import { ResultCache } from './result-cache.js';
-import * as cache from './crawlCache.js';
+import { crawl } from './crawler.js';
 import { AsyncFzf, FzfResultItem } from 'fzf';
 
-export type FileSearchOptions = {
+export interface FileSearchOptions {
   projectRoot: string;
   ignoreDirs: string[];
   useGitignore: boolean;
   useGeminiignore: boolean;
   cache: boolean;
   cacheTtl: number;
+  enableRecursiveFileSearch: boolean;
   maxDepth?: number;
-};
+}
 
 export class AbortError extends Error {
   constructor(message = 'Search aborted') {
@@ -78,54 +77,42 @@ export async function filter(
   return results;
 }
 
-export type SearchOptions = {
+export interface SearchOptions {
   signal?: AbortSignal;
   maxResults?: number;
-};
+}
 
-/**
- * Provides a fast and efficient way to search for files within a project,
- * respecting .gitignore and .geminiignore rules, and utilizing caching
- * for improved performance.
- */
-export class FileSearch {
-  private readonly absoluteDir: string;
-  private readonly ignore: Ignore = new Ignore();
+export interface FileSearch {
+  initialize(): Promise<void>;
+  search(pattern: string, options?: SearchOptions): Promise<string[]>;
+}
+
+class RecursiveFileSearch implements FileSearch {
+  private ignore: Ignore | undefined;
   private resultCache: ResultCache | undefined;
   private allFiles: string[] = [];
   private fzf: AsyncFzf<string[]> | undefined;
 
-  /**
-   * Constructs a new `FileSearch` instance.
-   * @param options Configuration options for the file search.
-   */
-  constructor(private readonly options: FileSearchOptions) {
-    this.absoluteDir = path.resolve(options.projectRoot);
-  }
+  constructor(private readonly options: FileSearchOptions) {}
 
-  /**
-   * Initializes the file search engine by loading ignore rules, crawling the
-   * file system, and building the in-memory cache. This method must be called
-   * before performing any searches.
-   */
   async initialize(): Promise<void> {
-    this.loadIgnoreRules();
-    await this.crawlFiles();
+    this.ignore = loadIgnoreRules(this.options);
+    this.allFiles = await crawl({
+      crawlDirectory: this.options.projectRoot,
+      cwd: this.options.projectRoot,
+      ignore: this.ignore,
+      cache: this.options.cache,
+      cacheTtl: this.options.cacheTtl,
+      maxDepth: this.options.maxDepth,
+    });
     this.buildResultCache();
   }
 
-  /**
-   * Searches for files matching a given pattern.
-   * @param pattern The picomatch pattern to search for (e.g., '*.js', 'src/**').
-   * @param options Search options, including an AbortSignal and maxResults.
-   * @returns A promise that resolves to a list of matching file paths, relative
-   *          to the project root.
-   */
   async search(
     pattern: string,
     options: SearchOptions = {},
   ): Promise<string[]> {
-    if (!this.resultCache || !this.fzf) {
+    if (!this.resultCache || !this.fzf || !this.ignore) {
       throw new Error('Engine not initialized. Call initialize() first.');
     }
 
@@ -159,21 +146,9 @@ export class FileSearch {
       }
     }
 
-    // Trade-off: We apply a two-stage filtering process.
-    // 1. During the file system crawl (`performCrawl`), we only apply directory-level
-    //    ignore rules (e.g., `node_modules/`, `dist/`). This is because applying
-    //    a full ignore filter (which includes file-specific patterns like `*.log`)
-    //    during the crawl can significantly slow down `fdir`.
-    // 2. Here, in the `search` method, we apply the full ignore filter
-    //    (including file patterns) to the `filteredCandidates` (which have already
-    //    been filtered by the user's search pattern and sorted). For autocomplete,
-    //    the number of displayed results is small (MAX_SUGGESTIONS_TO_SHOW),
-    //    so applying the full filter to this truncated list is much more efficient
-    //    than applying it to every file during the initial crawl.
     const fileFilter = this.ignore.getFileFilter();
     const results: string[] = [];
     for (const [i, candidate] of filteredCandidates.entries()) {
-      // Yield to the event loop to avoid blocking on large result sets.
       if (i % 1000 === 0) {
         await new Promise((resolve) => setImmediate(resolve));
         if (options.signal?.aborted) {
@@ -184,7 +159,6 @@ export class FileSearch {
       if (results.length >= (options.maxResults ?? Infinity)) {
         break;
       }
-      // The `ignore` library throws an error if the path is '.', so we skip it.
       if (candidate === '.') {
         continue;
       }
@@ -195,99 +169,6 @@ export class FileSearch {
     return results;
   }
 
-  /**
-   * Loads ignore rules from .gitignore and .geminiignore files, and applies
-   * any additional ignore directories specified in the options.
-   */
-  private loadIgnoreRules(): void {
-    if (this.options.useGitignore) {
-      const gitignorePath = path.join(this.absoluteDir, '.gitignore');
-      if (fs.existsSync(gitignorePath)) {
-        this.ignore.add(fs.readFileSync(gitignorePath, 'utf8'));
-      }
-    }
-
-    if (this.options.useGeminiignore) {
-      const geminiignorePath = path.join(this.absoluteDir, '.geminiignore');
-      if (fs.existsSync(geminiignorePath)) {
-        this.ignore.add(fs.readFileSync(geminiignorePath, 'utf8'));
-      }
-    }
-
-    const ignoreDirs = ['.git', ...this.options.ignoreDirs];
-    this.ignore.add(
-      ignoreDirs.map((dir) => {
-        if (dir.endsWith('/')) {
-          return dir;
-        }
-        return `${dir}/`;
-      }),
-    );
-  }
-
-  /**
-   * Crawls the file system to get a list of all files and directories,
-   * optionally using a cache for faster initialization.
-   */
-  private async crawlFiles(): Promise<void> {
-    if (this.options.cache) {
-      const cacheKey = cache.getCacheKey(
-        this.absoluteDir,
-        this.ignore.getFingerprint(),
-        this.options.maxDepth,
-      );
-      const cachedResults = cache.read(cacheKey);
-
-      if (cachedResults) {
-        this.allFiles = cachedResults;
-        return;
-      }
-    }
-
-    this.allFiles = await this.performCrawl();
-
-    if (this.options.cache) {
-      const cacheKey = cache.getCacheKey(
-        this.absoluteDir,
-        this.ignore.getFingerprint(),
-        this.options.maxDepth,
-      );
-      cache.write(cacheKey, this.allFiles, this.options.cacheTtl * 1000);
-    }
-  }
-
-  /**
-   * Performs the actual file system crawl using `fdir`, applying directory
-   * ignore rules.
-   * @returns A promise that resolves to a list of all files and directories.
-   */
-  private async performCrawl(): Promise<string[]> {
-    const dirFilter = this.ignore.getDirectoryFilter();
-
-    // We use `fdir` for fast file system traversal. A key performance
-    // optimization for large workspaces is to exclude entire directories
-    // early in the traversal process. This is why we apply directory-specific
-    // ignore rules (e.g., `node_modules/`, `dist/`) directly to `fdir`'s
-    // exclude filter.
-    const api = new fdir()
-      .withRelativePaths()
-      .withDirs()
-      .withPathSeparator('/') // Always use unix style paths
-      .exclude((_, dirPath) => {
-        const relativePath = path.relative(this.absoluteDir, dirPath);
-        return dirFilter(`${relativePath}/`);
-      });
-
-    if (this.options.maxDepth !== undefined) {
-      api.withMaxDepth(this.options.maxDepth);
-    }
-
-    return api.crawl(this.absoluteDir).withPromise();
-  }
-
-  /**
-   * Builds the in-memory cache for fast pattern matching.
-   */
   private buildResultCache(): void {
     this.resultCache = new ResultCache(this.allFiles);
     // The v1 algorithm is much faster since it only looks at the first
@@ -298,3 +179,59 @@ export class FileSearch {
     });
   }
 }
+
+class DirectoryFileSearch implements FileSearch {
+  private ignore: Ignore | undefined;
+
+  constructor(private readonly options: FileSearchOptions) {}
+
+  async initialize(): Promise<void> {
+    this.ignore = loadIgnoreRules(this.options);
+  }
+
+  async search(
+    pattern: string,
+    options: SearchOptions = {},
+  ): Promise<string[]> {
+    if (!this.ignore) {
+      throw new Error('Engine not initialized. Call initialize() first.');
+    }
+    pattern = pattern || '*';
+
+    const dir = pattern.endsWith('/') ? pattern : path.dirname(pattern);
+    const results = await crawl({
+      crawlDirectory: path.join(this.options.projectRoot, dir),
+      cwd: this.options.projectRoot,
+      maxDepth: 0,
+      ignore: this.ignore,
+      cache: this.options.cache,
+      cacheTtl: this.options.cacheTtl,
+    });
+
+    const filteredResults = await filter(results, pattern, options.signal);
+
+    const fileFilter = this.ignore.getFileFilter();
+    const finalResults: string[] = [];
+    for (const candidate of filteredResults) {
+      if (finalResults.length >= (options.maxResults ?? Infinity)) {
+        break;
+      }
+      if (candidate === '.') {
+        continue;
+      }
+      if (!fileFilter(candidate)) {
+        finalResults.push(candidate);
+      }
+    }
+    return finalResults;
+  }
+}
+
+export class FileSearchFactory {
+  static create(options: FileSearchOptions): FileSearch {
+    if (options.enableRecursiveFileSearch) {
+      return new RecursiveFileSearch(options);
+    }
+    return new DirectoryFileSearch(options);
+  }
+}
diff --git a/packages/core/src/utils/filesearch/ignore.test.ts b/packages/core/src/utils/filesearch/ignore.test.ts
index ff375e3f..f65ecd72 100644
--- a/packages/core/src/utils/filesearch/ignore.test.ts
+++ b/packages/core/src/utils/filesearch/ignore.test.ts
@@ -4,8 +4,9 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import { describe, it, expect } from 'vitest';
-import { Ignore } from './ignore.js';
+import { describe, it, expect, afterEach } from 'vitest';
+import { Ignore, loadIgnoreRules } from './ignore.js';
+import { createTmpDir, cleanupTmpDir } from '@google/gemini-cli-test-utils';
 
 describe('Ignore', () => {
   describe('getDirectoryFilter', () => {
@@ -63,3 +64,97 @@ describe('Ignore', () => {
     expect(ig1.getFingerprint()).not.toBe(ig2.getFingerprint());
   });
 });
+
+describe('loadIgnoreRules', () => {
+  let tmpDir: string;
+
+  afterEach(async () => {
+    if (tmpDir) {
+      await cleanupTmpDir(tmpDir);
+    }
+  });
+
+  it('should load rules from .gitignore', async () => {
+    tmpDir = await createTmpDir({
+      '.gitignore': '*.log',
+    });
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: false,
+      ignoreDirs: [],
+    });
+    const fileFilter = ignore.getFileFilter();
+    expect(fileFilter('test.log')).toBe(true);
+    expect(fileFilter('test.txt')).toBe(false);
+  });
+
+  it('should load rules from .geminiignore', async () => {
+    tmpDir = await createTmpDir({
+      '.geminiignore': '*.log',
+    });
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: false,
+      useGeminiignore: true,
+      ignoreDirs: [],
+    });
+    const fileFilter = ignore.getFileFilter();
+    expect(fileFilter('test.log')).toBe(true);
+    expect(fileFilter('test.txt')).toBe(false);
+  });
+
+  it('should combine rules from .gitignore and .geminiignore', async () => {
+    tmpDir = await createTmpDir({
+      '.gitignore': '*.log',
+      '.geminiignore': '*.txt',
+    });
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: true,
+      ignoreDirs: [],
+    });
+    const fileFilter = ignore.getFileFilter();
+    expect(fileFilter('test.log')).toBe(true);
+    expect(fileFilter('test.txt')).toBe(true);
+    expect(fileFilter('test.md')).toBe(false);
+  });
+
+  it('should add ignoreDirs', async () => {
+    tmpDir = await createTmpDir({});
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: false,
+      useGeminiignore: false,
+      ignoreDirs: ['logs/'],
+    });
+    const dirFilter = ignore.getDirectoryFilter();
+    expect(dirFilter('logs/')).toBe(true);
+    expect(dirFilter('src/')).toBe(false);
+  });
+
+  it('should handle missing ignore files gracefully', async () => {
+    tmpDir = await createTmpDir({});
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: true,
+      useGeminiignore: true,
+      ignoreDirs: [],
+    });
+    const fileFilter = ignore.getFileFilter();
+    expect(fileFilter('anyfile.txt')).toBe(false);
+  });
+
+  it('should always add .git to the ignore list', async () => {
+    tmpDir = await createTmpDir({});
+    const ignore = loadIgnoreRules({
+      projectRoot: tmpDir,
+      useGitignore: false,
+      useGeminiignore: false,
+      ignoreDirs: [],
+    });
+    const dirFilter = ignore.getDirectoryFilter();
+    expect(dirFilter('.git/')).toBe(true);
+  });
+});
diff --git a/packages/core/src/utils/filesearch/ignore.ts b/packages/core/src/utils/filesearch/ignore.ts
index 9f756f93..a39066f5 100644
--- a/packages/core/src/utils/filesearch/ignore.ts
+++ b/packages/core/src/utils/filesearch/ignore.ts
@@ -4,11 +4,49 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+import fs from 'node:fs';
+import path from 'node:path';
 import ignore from 'ignore';
 import picomatch from 'picomatch';
 
 const hasFileExtension = picomatch('**/*[*.]*');
 
+export interface LoadIgnoreRulesOptions {
+  projectRoot: string;
+  useGitignore: boolean;
+  useGeminiignore: boolean;
+  ignoreDirs: string[];
+}
+
+export function loadIgnoreRules(options: LoadIgnoreRulesOptions): Ignore {
+  const ignorer = new Ignore();
+  if (options.useGitignore) {
+    const gitignorePath = path.join(options.projectRoot, '.gitignore');
+    if (fs.existsSync(gitignorePath)) {
+      ignorer.add(fs.readFileSync(gitignorePath, 'utf8'));
+    }
+  }
+
+  if (options.useGeminiignore) {
+    const geminiignorePath = path.join(options.projectRoot, '.geminiignore');
+    if (fs.existsSync(geminiignorePath)) {
+      ignorer.add(fs.readFileSync(geminiignorePath, 'utf8'));
+    }
+  }
+
+  const ignoreDirs = ['.git', ...options.ignoreDirs];
+  ignorer.add(
+    ignoreDirs.map((dir) => {
+      if (dir.endsWith('/')) {
+        return dir;
+      }
+      return `${dir}/`;
+    }),
+  );
+
+  return ignorer;
+}
+
 export class Ignore {
   private readonly allPatterns: string[] = [];
   private dirIgnorer = ignore();