From 42bc280ad675bfaa7b1bbc192330fb582bb28172 Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Sun, 5 Apr 2026 22:21:43 +0200
Subject: [PATCH 01/11] fix(security): harden git arg handling and path
 validation

Resolves:
- https://github.com/Fcmam5/skilleton/security/code-scanning/1
- https://github.com/Fcmam5/skilleton/security/code-scanning/2
---
 SECURITY.md                | 18 ++++++++
 src/adapters/git.ts        | 50 +++++++++++++++++++--
 tests/adapters.git.test.ts | 90 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 154 insertions(+), 4 deletions(-)
 create mode 100644 tests/adapters.git.test.ts

diff --git a/SECURITY.md b/SECURITY.md
index 77c9564..7c4bca0 100644
--- a/SECURITY.md
+++ b/SECURITY.md
@@ -35,6 +35,24 @@ Instead, email `au54vz9rk[at]mozmail[.]com` with the details. If you do not rece
 
 We may invite you to test the fix before release if appropriate.
 
+### Automated Alert Triage (GitHub)
+
+We also monitor and triage GitHub security signals (CodeQL and Dependabot alerts).
+
+- **Initial triage SLA**: within 7 days of an alert opening
+- **Critical/High**: patch or documented mitigation target within 14 days
+- **Medium**: patch target within 30 days
+- **Low**: patch target within 90 days or explicitly risk-accepted with rationale
+
+For each alert, we track:
+
+- affected file/function and exploit preconditions
+- real impact in Skilleton runtime/CLI context
+- patch approach, owner, and target release
+- verification (tests and/or reproduction before/after)
+
+If an alert is a false positive or accepted risk, we record the reason and keep the decision reviewable.
+
 ## Scope
 
 This policy covers:
diff --git a/src/adapters/git.ts b/src/adapters/git.ts
index 9362406..83ed7a6 100644
--- a/src/adapters/git.ts
+++ b/src/adapters/git.ts
@@ -7,6 +7,10 @@ import { getCacheRoot } from '../core/config';
 import { ensureRepoUrl, repoCacheKey } from '../core/repos';
 import { SkillInstallError } from '../core/errors';
 
+// Reference: https://git-scm.com/book/en/v2/Git-Tools-Revision-Selection
+// Pattern to match a 40-character hexadecimal SHA-1 hash
+const COMMIT_SHA_PATTERN = /^[0-9a-f]{40}$/i;
+
 async function pathExists(target: string): Promise<boolean> {
   try {
     await fs.access(target);
@@ -16,6 +20,34 @@ async function pathExists(target: string): Promise<boolean> {
   }
 }
 
+// Rejects values that could be interpreted as git options or null bytes
+// This is a security measure to prevent command injection when passing values to git commands as arguments
+function assertSafeGitArg(value: string, label: string): void {
+  if (!value || value.includes('\0') || value.startsWith('-')) {
+    throw new SkillInstallError(`Invalid ${label}`);
+  }
+}
+
+// Resolves a sub-path relative to a base directory, ensuring it stays within the base.
+// Rejects absolute paths and paths that would escape the base directory.
+function resolveSafeSubPath(baseDir: string, subPath?: string): string {
+  if (!subPath || subPath === '.') {
+    return baseDir;
+  }
+
+  if (path.isAbsolute(subPath)) {
+    throw new SkillInstallError(`Invalid skill path ${subPath}`);
+  }
+
+  const normalized = path.resolve(baseDir, subPath);
+  const relativeToBase = path.relative(baseDir, normalized);
+  if (relativeToBase.startsWith('..') || path.isAbsolute(relativeToBase)) {
+    throw new SkillInstallError(`Invalid skill path ${subPath}`);
+  }
+
+  return normalized;
+}
+
 /** Git client implementation backed by `execa` shell commands. */
 export class ExecaGitClient implements GitClient {
   constructor(private readonly cacheRoot = getCacheRoot()) {}
@@ -31,9 +63,14 @@ export class ExecaGitClient implements GitClient {
     const cloneSource = `${repoUrl}.git`.replace(/\.git\.git$/i, '.git');
     const gitEnv = { ...process.env, GIT_TERMINAL_PROMPT: '0' };
 
+    // Security: Validate paths to prevent command injection
+    assertSafeGitArg(repoCachePath, 'repository cache path');
+    assertSafeGitArg(cloneSource, 'repository URL');
+
     if (!(await pathExists(repoCachePath))) {
       await fs.mkdir(path.dirname(repoCachePath), { recursive: true });
-      await execa('git', ['clone', '--filter=blob:none', cloneSource, repoCachePath], {
+      // Security: Validate paths to prevent command injection
+      await execa('git', ['clone', '--filter=blob:none', '--', cloneSource, repoCachePath], {
         timeout: 30000,
         env: gitEnv,
         stdin: 'ignore',
@@ -61,6 +98,12 @@ export class ExecaGitClient implements GitClient {
    * @param subPath Optional subdirectory within the repository.
    */
   async exportPath(repoPath: string, commit: string, destination: string, subPath?: string): Promise<void> {
+    assertSafeGitArg(repoPath, 'repository path');
+    assertSafeGitArg(destination, 'destination path');
+    if (!COMMIT_SHA_PATTERN.test(commit)) {
+      throw new SkillInstallError(`Invalid commit SHA: ${commit}`);
+    }
+
     const worktreeDir = await fs.mkdtemp(path.join(os.tmpdir(), 'skilleton-wt-'));
     const gitEnv = { ...process.env, GIT_TERMINAL_PROMPT: '0' };
 
@@ -73,10 +116,9 @@ export class ExecaGitClient implements GitClient {
         stderr: 'pipe',
       });
 
-      const relative = subPath && subPath !== '.' ? subPath : undefined;
-      const sourcePath = relative ? path.join(worktreeDir, relative) : worktreeDir;
+      const sourcePath = resolveSafeSubPath(worktreeDir, subPath);
       if (!(await pathExists(sourcePath))) {
-        throw new SkillInstallError(`Skill path ${relative ?? '.'} not found in repository ${repoPath}`);
+        throw new SkillInstallError(`Skill path ${subPath ?? '.'} not found in repository ${repoPath}`);
       }
 
       await fs.rm(destination, { recursive: true, force: true });
diff --git a/tests/adapters.git.test.ts b/tests/adapters.git.test.ts
new file mode 100644
index 0000000..e39e3a8
--- /dev/null
+++ b/tests/adapters.git.test.ts
@@ -0,0 +1,90 @@
+import { promises as fs } from 'node:fs';
+import { execa } from 'execa';
+import { ExecaGitClient } from '../src/adapters/git';
+import { SkillInstallError } from '../src/core/errors';
+
+jest.mock('execa');
+jest.mock('node:fs', () => ({
+  promises: {
+    access: jest.fn(),
+    mkdir: jest.fn(),
+    rm: jest.fn(),
+    cp: jest.fn(),
+    mkdtemp: jest.fn(),
+  },
+}));
+
+describe('ExecaGitClient security hardening', () => {
+  const mockedFs = fs as unknown as {
+    access: jest.Mock;
+    mkdir: jest.Mock;
+    rm: jest.Mock;
+    cp: jest.Mock;
+    mkdtemp: jest.Mock;
+  };
+  const mockedExeca = execa as unknown as jest.Mock;
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+    mockedFs.access.mockResolvedValue(undefined);
+    mockedFs.mkdir.mockResolvedValue(undefined);
+    mockedFs.rm.mockResolvedValue(undefined);
+    mockedFs.cp.mockResolvedValue(undefined);
+    mockedFs.mkdtemp.mockResolvedValue('/tmp/skilleton-wt-123');
+    mockedExeca.mockResolvedValue({ stdout: '', stderr: '' });
+  });
+
+  it('uses -- separator for git clone arguments', async () => {
+    mockedFs.access.mockRejectedValueOnce(new Error('missing'));
+    const client = new ExecaGitClient('/tmp/cache');
+
+    await client.ensureRepo('https://github.com/acme/skills');
+
+    expect(mockedExeca).toHaveBeenCalledWith(
+      'git',
+      ['clone', '--filter=blob:none', '--', 'https://github.com/acme/skills.git', '/tmp/cache/https_github.com_acme_skills'],
+      expect.any(Object),
+    );
+  });
+
+  it('rejects destination values that look like git options', async () => {
+    const client = new ExecaGitClient('/tmp/cache');
+
+    await expect(client.ensureRepo('https://github.com/acme/skills', '--upload-pack=sh')).rejects.toThrow(SkillInstallError);
+    await expect(client.ensureRepo('https://github.com/acme/skills', '--upload-pack=sh')).rejects.toThrow(
+      'Invalid repository cache path',
+    );
+    expect(mockedExeca).not.toHaveBeenCalled();
+  });
+
+  it('rejects non-SHA commit inputs before running git worktree', async () => {
+    const client = new ExecaGitClient('/tmp/cache');
+
+    await expect(client.exportPath('/tmp/cache/repo', 'main', '/tmp/out', 'skills/jest')).rejects.toThrow(SkillInstallError);
+    await expect(client.exportPath('/tmp/cache/repo', 'main', '/tmp/out', 'skills/jest')).rejects.toThrow(
+      'Invalid commit SHA: main',
+    );
+    expect(mockedExeca).not.toHaveBeenCalled();
+    expect(mockedFs.mkdtemp).not.toHaveBeenCalled();
+  });
+
+  it('rejects path traversal in subPath', async () => {
+    const client = new ExecaGitClient('/tmp/cache');
+    const commit = 'abcdef1234567890abcdef1234567890abcdef12';
+
+    await expect(client.exportPath('/tmp/cache/repo', commit, '/tmp/out', '../escape')).rejects.toThrow(
+      'Invalid skill path ../escape',
+    );
+
+    expect(mockedExeca).toHaveBeenCalledWith(
+      'git',
+      ['-C', '/tmp/cache/repo', 'worktree', 'add', '--force', '--detach', '/tmp/skilleton-wt-123', commit],
+      expect.any(Object),
+    );
+    expect(mockedExeca).toHaveBeenCalledWith(
+      'git',
+      ['-C', '/tmp/cache/repo', 'worktree', 'remove', '--force', '/tmp/skilleton-wt-123'],
+      expect.any(Object),
+    );
+  });
+});

From 3f83f7259b2ebbaf15f6f0b48d5787eb67d49e8d Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Sun, 5 Apr 2026 22:59:48 +0200
Subject: [PATCH 02/11] fix(security): setup eslint-plugin-security and fix
 findings

---
 bin/skilleton.ts         | 42 ++++++++++++++++++++++++++++++----------
 eslint.config.cjs        |  5 +++++
 package-lock.json        | 37 +++++++++++++++++++++++++++++++++++
 package.json             |  1 +
 src/commands/describe.ts | 14 +++++++++++++-
 src/core/lock.ts         | 19 +++++++-----------
 tests/describe.test.ts   |  1 +
 7 files changed, 96 insertions(+), 23 deletions(-)

diff --git a/bin/skilleton.ts b/bin/skilleton.ts
index 8bba673..63b9ce9 100644
--- a/bin/skilleton.ts
+++ b/bin/skilleton.ts
@@ -20,41 +20,63 @@ const commands: CommandRegistry = {
   audit: new AuditCommand(),
 };
 
+function getCommandHandler(command: string): Command | null {
+  switch (command) {
+    case 'add':
+      return commands.add;
+    case 'install':
+      return commands.install;
+    case 'update':
+      return commands.update;
+    case 'list':
+      return commands.list;
+    case 'describe':
+      return commands.describe;
+    case 'audit':
+      return commands.audit;
+    default:
+      return null;
+  }
+}
+
 function parseArgs(argv: string[]): { command: string | null; args: CommandArgs } {
   if (argv.length === 0) {
     return { command: null, args: { positional: [], flags: {} } };
   }
 
   const [command, ...rest] = argv;
+  const tokens = [...rest];
   const positional: string[] = [];
-  const flags: Record<string, string | boolean> = {};
+  const flagsMap = new Map<string, string | boolean>();
 
-  for (let i = 0; i < rest.length; i += 1) {
-    const token = rest[i];
+  while (tokens.length > 0) {
+    const token = tokens.shift()!;
     if (token.startsWith('--')) {
       const [rawFlag, value] = token.slice(2).split('=');
       const flag = rawFlag === 'h' ? 'help' : rawFlag;
       if (value !== undefined) {
-        flags[flag] = value;
+        flagsMap.set(flag, value);
         continue;
       }
 
-      const next = rest[i + 1];
+      const next = tokens[0];
       if (next && !next.startsWith('-')) {
-        flags[flag] = next;
-        i += 1;
+        flagsMap.set(flag, next);
+        tokens.shift();
       } else {
-        flags[flag] = true;
+        flagsMap.set(flag, true);
       }
     } else if (token.startsWith('-') && token.length > 1) {
       const rawFlag = token.slice(1);
       const flag = rawFlag === 'h' ? 'help' : rawFlag;
-      flags[flag] = true;
+      flagsMap.set(flag, true);
     } else {
       positional.push(token);
     }
   }
 
+  const flags = Object.fromEntries(flagsMap);
+
   return { command, args: { positional, flags } };
 }
 
@@ -81,7 +103,7 @@ async function main(): Promise<void> {
   }
 
   // Validate command first
-  const handler = commands[command];
+  const handler = getCommandHandler(command);
   if (!handler) {
     console.error(`Unknown command: ${command}`);
     printHelp();
diff --git a/eslint.config.cjs b/eslint.config.cjs
index 48f4ad8..45b387d 100644
--- a/eslint.config.cjs
+++ b/eslint.config.cjs
@@ -1,5 +1,6 @@
 const tseslint = require('typescript-eslint');
 const globals = require('globals');
+const security = require('eslint-plugin-security');
 
 module.exports = [
   {
@@ -8,6 +9,9 @@ module.exports = [
   ...tseslint.configs.recommended,
   {
     files: ['**/*.ts'],
+    plugins: {
+      security,
+    },
     languageOptions: {
       globals: globals.node,
       parser: tseslint.parser,
@@ -17,6 +21,7 @@ module.exports = [
       },
     },
     rules: {
+      ...security.configs.recommended.rules,
       'no-unused-vars': 'off',
       '@typescript-eslint/no-unused-vars': ['warn', { argsIgnorePattern: '^_', varsIgnorePattern: '^_' }],
     },
diff --git a/package-lock.json b/package-lock.json
index ce7a43c..8d57b25 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -23,6 +23,7 @@
         "@types/node": "^25.5.0",
         "eslint": "^10.1.0",
         "eslint-config-prettier": "^10.1.8",
+        "eslint-plugin-security": "^4.0.0",
         "globals": "^17.4.0",
         "jest": "^30.3.0",
         "prettier": "^3.8.1",
@@ -2970,6 +2971,22 @@
         "eslint": ">=7.0.0"
       }
     },
+    "node_modules/eslint-plugin-security": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/eslint-plugin-security/-/eslint-plugin-security-4.0.0.tgz",
+      "integrity": "sha512-tfuQT8K/Li1ZxhFzyD8wPIKtlzZxqBcPr9q0jFMQ77wWAbKBVEhaMPVQRTMTvCMUDhwBe5vPVqQPwAGk/ASfxQ==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "dependencies": {
+        "safe-regex": "^2.1.1"
+      },
+      "engines": {
+        "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
+      },
+      "funding": {
+        "url": "https://opencollective.com/eslint"
+      }
+    },
     "node_modules/eslint-scope": {
       "version": "9.1.2",
       "resolved": "https://registry.npmjs.org/eslint-scope/-/eslint-scope-9.1.2.tgz",
@@ -5256,6 +5273,16 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/regexp-tree": {
+      "version": "0.1.27",
+      "resolved": "https://registry.npmjs.org/regexp-tree/-/regexp-tree-0.1.27.tgz",
+      "integrity": "sha512-iETxpjK6YoRWJG5o6hXLwvjYAoW+FEZn9os0PD/b6AP6xQwsa/Y7lCVgIixBbUPMfhu+i2LtdeAqVTgGlQarfA==",
+      "dev": true,
+      "license": "MIT",
+      "bin": {
+        "regexp-tree": "bin/regexp-tree"
+      }
+    },
     "node_modules/require-directory": {
       "version": "2.1.1",
       "resolved": "https://registry.npmjs.org/require-directory/-/require-directory-2.1.1.tgz",
@@ -5298,6 +5325,16 @@
         "node": ">=8"
       }
     },
+    "node_modules/safe-regex": {
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/safe-regex/-/safe-regex-2.1.1.tgz",
+      "integrity": "sha512-rx+x8AMzKb5Q5lQ95Zoi6ZbJqwCLkqi3XuJXp5P3rT8OEc6sZCJG5AE5dU3lsgRr/F4Bs31jSlVN+j5KrsGu9A==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "regexp-tree": "~0.1.1"
+      }
+    },
     "node_modules/semver": {
       "version": "6.3.1",
       "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.1.tgz",
diff --git a/package.json b/package.json
index d411842..62c718e 100644
--- a/package.json
+++ b/package.json
@@ -61,6 +61,7 @@
     "@types/node": "^25.5.0",
     "eslint": "^10.1.0",
     "eslint-config-prettier": "^10.1.8",
+    "eslint-plugin-security": "^4.0.0",
     "globals": "^17.4.0",
     "jest": "^30.3.0",
     "prettier": "^3.8.1",
diff --git a/src/commands/describe.ts b/src/commands/describe.ts
index 6478293..d07dfff 100644
--- a/src/commands/describe.ts
+++ b/src/commands/describe.ts
@@ -21,7 +21,7 @@ export class DescribeCommand implements Command {
       }
 
       const lockfile = await env.manifestRepo.readLockfileIfExists();
-      const locked = lockfile?.skills?.[skillName];
+      const locked = this.getLockedSkillByName(lockfile, skillName);
       const installPath = env.manifestRepo.skillInstallPath(skillName);
       const installed = await env.fs.pathExists(installPath);
 
@@ -44,6 +44,18 @@ export class DescribeCommand implements Command {
     }
   }
 
+  private getLockedSkillByName(
+    lockfile: { skills: Record<string, LockedSkill> } | null,
+    skillName: string,
+  ): LockedSkill | undefined {
+    if (!lockfile) {
+      return undefined;
+    }
+
+    const skillsByName = new Map(Object.entries(lockfile.skills));
+    return skillsByName.get(skillName);
+  }
+
   private printMetadata(
     skill: SkillDescriptor,
     locked: LockedSkill | undefined,
diff --git a/src/core/lock.ts b/src/core/lock.ts
index 6ae971d..f513144 100644
--- a/src/core/lock.ts
+++ b/src/core/lock.ts
@@ -40,10 +40,7 @@ export interface ReconcileLockfileResult {
 
 /** Converts resolved skills into lockfile record format keyed by skill name. */
 export function serializeLockfile(skills: LockedSkill[]): SkillLockfile {
-  const record: SkillLockfile['skills'] = {};
-  for (const skill of skills) {
-    record[skill.name] = skill;
-  }
+  const record = Object.fromEntries(skills.map((skill) => [skill.name, skill])) as SkillLockfile['skills'];
   return { skills: record };
 }
 
@@ -53,8 +50,10 @@ export function getChangedSkills(nextSkills: LockedSkill[], previous: SkillLockf
     return nextSkills;
   }
 
+  const priorByName = new Map(Object.entries(previous.skills));
+
   return nextSkills.filter((skill) => {
-    const prior = previous.skills[skill.name];
+    const prior = priorByName.get(skill.name);
     if (!prior) {
       return true;
     }
@@ -67,13 +66,9 @@ export function getChangedSkills(nextSkills: LockedSkill[], previous: SkillLockf
 /** Removes lockfile entries whose skill names are no longer declared. */
 export function pruneLockfile(lockfile: SkillLockfile, names: string[]): SkillLockfile {
   const keep = new Set(names);
-  const nextSkills: SkillLockfile['skills'] = {};
-
-  for (const [name, skill] of Object.entries(lockfile.skills)) {
-    if (keep.has(name)) {
-      nextSkills[name] = skill;
-    }
-  }
+  const nextSkills = Object.fromEntries(
+    Object.entries(lockfile.skills).filter(([name]) => keep.has(name)),
+  ) as SkillLockfile['skills'];
 
   return { skills: nextSkills };
 }
diff --git a/tests/describe.test.ts b/tests/describe.test.ts
index 18ea6ea..6708876 100644
--- a/tests/describe.test.ts
+++ b/tests/describe.test.ts
@@ -207,6 +207,7 @@ function createEnv(options: CreateEnvOptions = {}): SkilletonEnvironment {
       return lockfile;
     },
     skillInstallPath(skillName: string) {
+      // eslint-disable-next-line security/detect-object-injection
       return installPaths[skillName] ?? `/repo/.skilleton/skills/${skillName}`;
     },
   };

From 0a4b0ba8c16f795574c223fa45dc8d889ed6c382 Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Sun, 5 Apr 2026 23:14:29 +0200
Subject: [PATCH 03/11] refactor: Use own FS wrapper

---
 eslint.config.cjs          | 24 ++++++++++++++
 src/adapters/git.ts        | 33 ++++++++----------
 src/core/filesystem.ts     |  4 +++
 src/core/types.ts          |  1 +
 tests/adapters.git.test.ts | 68 ++++++++++++++++++++++----------------
 tests/describe.test.ts     |  6 ++++
 tests/install.test.ts      |  1 +
 7 files changed, 88 insertions(+), 49 deletions(-)

diff --git a/eslint.config.cjs b/eslint.config.cjs
index 45b387d..0ae33c7 100644
--- a/eslint.config.cjs
+++ b/eslint.config.cjs
@@ -2,6 +2,8 @@ const tseslint = require('typescript-eslint');
 const globals = require('globals');
 const security = require('eslint-plugin-security');
 
+const FILESYSTEM_IMPORT_MESSAGE = 'Use FileSystem from src/core/filesystem.ts instead of importing node:fs directly.';
+
 module.exports = [
   {
     ignores: ['dist/**', 'coverage/**', 'package-lock.json', '**/*.json'],
@@ -22,10 +24,32 @@ module.exports = [
     },
     rules: {
       ...security.configs.recommended.rules,
+      'no-restricted-imports': [
+        'error',
+        {
+          paths: [
+            {
+              name: 'node:fs',
+              message: FILESYSTEM_IMPORT_MESSAGE,
+            },
+            {
+              name: 'node:fs/promises',
+              message: FILESYSTEM_IMPORT_MESSAGE,
+            },
+          ],
+        },
+      ],
       'no-unused-vars': 'off',
       '@typescript-eslint/no-unused-vars': ['warn', { argsIgnorePattern: '^_', varsIgnorePattern: '^_' }],
     },
   },
+  {
+    files: ['src/core/filesystem.ts'],
+    rules: {
+      'no-restricted-imports': 'off',
+      'security/detect-non-literal-fs-filename': 'off', // We expect controlled/validated inputs
+    },
+  },
   {
     files: ['eslint.config.cjs'],
     rules: {
diff --git a/src/adapters/git.ts b/src/adapters/git.ts
index 83ed7a6..ccb9a9d 100644
--- a/src/adapters/git.ts
+++ b/src/adapters/git.ts
@@ -1,25 +1,16 @@
-import { promises as fs } from 'node:fs';
 import os from 'node:os';
 import path from 'node:path';
 import { execa } from 'execa';
-import { GitClient } from '../core/types';
+import { FileSystem, GitClient } from '../core/types';
 import { getCacheRoot } from '../core/config';
 import { ensureRepoUrl, repoCacheKey } from '../core/repos';
 import { SkillInstallError } from '../core/errors';
+import { NodeFileSystem } from '../core/filesystem';
 
 // Reference: https://git-scm.com/book/en/v2/Git-Tools-Revision-Selection
 // Pattern to match a 40-character hexadecimal SHA-1 hash
 const COMMIT_SHA_PATTERN = /^[0-9a-f]{40}$/i;
 
-async function pathExists(target: string): Promise<boolean> {
-  try {
-    await fs.access(target);
-    return true;
-  } catch {
-    return false;
-  }
-}
-
 // Rejects values that could be interpreted as git options or null bytes
 // This is a security measure to prevent command injection when passing values to git commands as arguments
 function assertSafeGitArg(value: string, label: string): void {
@@ -50,7 +41,10 @@ function resolveSafeSubPath(baseDir: string, subPath?: string): string {
 
 /** Git client implementation backed by `execa` shell commands. */
 export class ExecaGitClient implements GitClient {
-  constructor(private readonly cacheRoot = getCacheRoot()) {}
+  constructor(
+    private readonly cacheRoot = getCacheRoot(),
+    private readonly fs: FileSystem = new NodeFileSystem(),
+  ) {}
 
   /**
    * Ensures a repository is present in local cache and fetches updates when already cloned.
@@ -67,8 +61,8 @@ export class ExecaGitClient implements GitClient {
     assertSafeGitArg(repoCachePath, 'repository cache path');
     assertSafeGitArg(cloneSource, 'repository URL');
 
-    if (!(await pathExists(repoCachePath))) {
-      await fs.mkdir(path.dirname(repoCachePath), { recursive: true });
+    if (!(await this.fs.pathExists(repoCachePath))) {
+      await this.fs.ensureDir(path.dirname(repoCachePath));
       // Security: Validate paths to prevent command injection
       await execa('git', ['clone', '--filter=blob:none', '--', cloneSource, repoCachePath], {
         timeout: 30000,
@@ -104,7 +98,7 @@ export class ExecaGitClient implements GitClient {
       throw new SkillInstallError(`Invalid commit SHA: ${commit}`);
     }
 
-    const worktreeDir = await fs.mkdtemp(path.join(os.tmpdir(), 'skilleton-wt-'));
+    const worktreeDir = await this.fs.mkdtemp(path.join(os.tmpdir(), 'skilleton-wt-'));
     const gitEnv = { ...process.env, GIT_TERMINAL_PROMPT: '0' };
 
     try {
@@ -117,13 +111,12 @@ export class ExecaGitClient implements GitClient {
       });
 
       const sourcePath = resolveSafeSubPath(worktreeDir, subPath);
-      if (!(await pathExists(sourcePath))) {
+      if (!(await this.fs.pathExists(sourcePath))) {
         throw new SkillInstallError(`Skill path ${subPath ?? '.'} not found in repository ${repoPath}`);
       }
 
-      await fs.rm(destination, { recursive: true, force: true });
-      await fs.mkdir(path.dirname(destination), { recursive: true });
-      await fs.cp(sourcePath, destination, { recursive: true });
+      await this.fs.remove(destination);
+      await this.fs.copy(sourcePath, destination);
     } catch (error) {
       throw new SkillInstallError(
         `Failed to export ${subPath ?? '.'} from ${repoPath}@${commit}: ${(error as Error).message}`,
@@ -136,7 +129,7 @@ export class ExecaGitClient implements GitClient {
         stdout: 'pipe',
         stderr: 'pipe',
       }).catch(() => undefined);
-      await fs.rm(worktreeDir, { recursive: true, force: true }).catch(() => undefined);
+      await this.fs.remove(worktreeDir).catch(() => undefined);
     }
   }
 }
diff --git a/src/core/filesystem.ts b/src/core/filesystem.ts
index f7d9b91..6710a58 100644
--- a/src/core/filesystem.ts
+++ b/src/core/filesystem.ts
@@ -30,6 +30,10 @@ export class NodeFileSystem implements FileSystem {
     await fs.mkdir(target, { recursive: true });
   }
 
+  async mkdtemp(prefix: string): Promise<string> {
+    return fs.mkdtemp(prefix);
+  }
+
   /**
    * Reads and parses JSON from disk.
    * @param target JSON file path.
diff --git a/src/core/types.ts b/src/core/types.ts
index 033d667..45e4df0 100644
--- a/src/core/types.ts
+++ b/src/core/types.ts
@@ -44,6 +44,7 @@ export interface GitClient {
 export interface FileSystem {
   pathExists(_path: string): Promise<boolean>;
   ensureDir(_path: string): Promise<void>;
+  mkdtemp(_prefix: string): Promise<string>;
   readJson<T>(_path: string): Promise<T>;
   writeJson(_path: string, _data: unknown): Promise<void>;
   readFile(_path: string): Promise<string>;
diff --git a/tests/adapters.git.test.ts b/tests/adapters.git.test.ts
index e39e3a8..1426163 100644
--- a/tests/adapters.git.test.ts
+++ b/tests/adapters.git.test.ts
@@ -1,56 +1,64 @@
-import { promises as fs } from 'node:fs';
 import { execa } from 'execa';
 import { ExecaGitClient } from '../src/adapters/git';
 import { SkillInstallError } from '../src/core/errors';
+import { FileSystem } from '../src/core/types';
 
 jest.mock('execa');
-jest.mock('node:fs', () => ({
-  promises: {
-    access: jest.fn(),
-    mkdir: jest.fn(),
-    rm: jest.fn(),
-    cp: jest.fn(),
-    mkdtemp: jest.fn(),
-  },
-}));
+
+const createFsMock = (): jest.Mocked<FileSystem> => ({
+  pathExists: jest.fn(),
+  ensureDir: jest.fn(),
+  mkdtemp: jest.fn(),
+  readJson: jest.fn(),
+  writeJson: jest.fn(),
+  readFile: jest.fn(),
+  isDirectory: jest.fn(),
+  remove: jest.fn(),
+  copy: jest.fn(),
+  symlink: jest.fn(),
+  readDir: jest.fn(),
+});
 
 describe('ExecaGitClient security hardening', () => {
-  const mockedFs = fs as unknown as {
-    access: jest.Mock;
-    mkdir: jest.Mock;
-    rm: jest.Mock;
-    cp: jest.Mock;
-    mkdtemp: jest.Mock;
-  };
+  let mockedFs: jest.Mocked<FileSystem>;
   const mockedExeca = execa as unknown as jest.Mock;
 
   beforeEach(() => {
     jest.clearAllMocks();
-    mockedFs.access.mockResolvedValue(undefined);
-    mockedFs.mkdir.mockResolvedValue(undefined);
-    mockedFs.rm.mockResolvedValue(undefined);
-    mockedFs.cp.mockResolvedValue(undefined);
+    mockedFs = createFsMock();
+    mockedFs.pathExists.mockResolvedValue(true);
+    mockedFs.ensureDir.mockResolvedValue(undefined);
+    mockedFs.remove.mockResolvedValue(undefined);
+    mockedFs.copy.mockResolvedValue(undefined);
     mockedFs.mkdtemp.mockResolvedValue('/tmp/skilleton-wt-123');
     mockedExeca.mockResolvedValue({ stdout: '', stderr: '' });
   });
 
   it('uses -- separator for git clone arguments', async () => {
-    mockedFs.access.mockRejectedValueOnce(new Error('missing'));
-    const client = new ExecaGitClient('/tmp/cache');
+    mockedFs.pathExists.mockResolvedValueOnce(false);
+    const client = new ExecaGitClient('/tmp/cache', mockedFs);
 
     await client.ensureRepo('https://github.com/acme/skills');
 
     expect(mockedExeca).toHaveBeenCalledWith(
       'git',
-      ['clone', '--filter=blob:none', '--', 'https://github.com/acme/skills.git', '/tmp/cache/https_github.com_acme_skills'],
+      [
+        'clone',
+        '--filter=blob:none',
+        '--',
+        'https://github.com/acme/skills.git',
+        '/tmp/cache/https_github.com_acme_skills',
+      ],
       expect.any(Object),
     );
   });
 
   it('rejects destination values that look like git options', async () => {
-    const client = new ExecaGitClient('/tmp/cache');
+    const client = new ExecaGitClient('/tmp/cache', mockedFs);
 
-    await expect(client.ensureRepo('https://github.com/acme/skills', '--upload-pack=sh')).rejects.toThrow(SkillInstallError);
+    await expect(client.ensureRepo('https://github.com/acme/skills', '--upload-pack=sh')).rejects.toThrow(
+      SkillInstallError,
+    );
     await expect(client.ensureRepo('https://github.com/acme/skills', '--upload-pack=sh')).rejects.toThrow(
       'Invalid repository cache path',
     );
@@ -58,9 +66,11 @@ describe('ExecaGitClient security hardening', () => {
   });
 
   it('rejects non-SHA commit inputs before running git worktree', async () => {
-    const client = new ExecaGitClient('/tmp/cache');
+    const client = new ExecaGitClient('/tmp/cache', mockedFs);
 
-    await expect(client.exportPath('/tmp/cache/repo', 'main', '/tmp/out', 'skills/jest')).rejects.toThrow(SkillInstallError);
+    await expect(client.exportPath('/tmp/cache/repo', 'main', '/tmp/out', 'skills/jest')).rejects.toThrow(
+      SkillInstallError,
+    );
     await expect(client.exportPath('/tmp/cache/repo', 'main', '/tmp/out', 'skills/jest')).rejects.toThrow(
       'Invalid commit SHA: main',
     );
@@ -69,7 +79,7 @@ describe('ExecaGitClient security hardening', () => {
   });
 
   it('rejects path traversal in subPath', async () => {
-    const client = new ExecaGitClient('/tmp/cache');
+    const client = new ExecaGitClient('/tmp/cache', mockedFs);
     const commit = 'abcdef1234567890abcdef1234567890abcdef12';
 
     await expect(client.exportPath('/tmp/cache/repo', commit, '/tmp/out', '../escape')).rejects.toThrow(
diff --git a/tests/describe.test.ts b/tests/describe.test.ts
index 6708876..35e29bb 100644
--- a/tests/describe.test.ts
+++ b/tests/describe.test.ts
@@ -274,6 +274,12 @@ class InMemoryFileSystem implements FileSystem {
     this.directories.add(this.normalize(target));
   }
 
+  async mkdtemp(prefix: string): Promise<string> {
+    const tempDir = this.normalize(`${prefix}tmp`);
+    this.directories.add(tempDir);
+    return tempDir;
+  }
+
   async readJson<T>(_path: string): Promise<T> {
     throw new Error('Not implemented');
   }
diff --git a/tests/install.test.ts b/tests/install.test.ts
index d28e759..3d6a054 100644
--- a/tests/install.test.ts
+++ b/tests/install.test.ts
@@ -6,6 +6,7 @@ import { SkillInstallError } from '../src/core/errors';
 const createFsMock = (): jest.Mocked<FileSystem> => ({
   pathExists: jest.fn(),
   ensureDir: jest.fn(),
+  mkdtemp: jest.fn(),
   readJson: jest.fn(),
   writeJson: jest.fn(),
   readFile: jest.fn(),

From 6613160803ec8655efee9a270eeaa767ad22da8b Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Sun, 5 Apr 2026 23:34:50 +0200
Subject: [PATCH 04/11] fix(security): use while loop in normalizeRepoUrl
 instead of regex

This resolves https://github.com/Fcmam5/skilleton/security/code-scanning/3
---
 src/core/repos.ts | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/core/repos.ts b/src/core/repos.ts
index 7beb19d..980d777 100644
--- a/src/core/repos.ts
+++ b/src/core/repos.ts
@@ -24,8 +24,13 @@ export function isRepoUrl(spec: string): boolean {
 
 /** Normalizes repository URLs by removing trailing slash and `.git`. */
 export function normalizeRepoUrl(url: string): string {
-  const withoutTrailingSlash = url.replace(/\/+$/, '');
-  return withoutTrailingSlash.replace(/\.git$/i, '');
+  let normalized = url;
+  // Using a deterministic while loop to remove trailing slashes instead of regex
+  // This closes "Polynomial regular expression used on uncontrolled data" warning (code scanning #3)
+  while (normalized.endsWith('/')) {
+    normalized = normalized.slice(0, -1);
+  }
+  return normalized.replace(/\.git$/i, '');
 }
 
 /** Normalizes owner/repo or URL-like specs into a canonical repository URL. */

From a186fc6193c5da35f2146b42cd11fab9bfd15a29 Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Sun, 5 Apr 2026 23:41:42 +0200
Subject: [PATCH 05/11] chore: update dependencies

---
 package-lock.json | 250 ++++++++++++++++++++++++----------------------
 package.json      |  10 +-
 2 files changed, 137 insertions(+), 123 deletions(-)

diff --git a/package-lock.json b/package-lock.json
index 8d57b25..2a0e0f5 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -20,18 +20,18 @@
         "@eslint/js": "^10.0.1",
         "@eslint/json": "^1.2.0",
         "@types/jest": "^30.0.0",
-        "@types/node": "^25.5.0",
-        "eslint": "^10.1.0",
+        "@types/node": "^25.5.2",
+        "eslint": "^10.2.0",
         "eslint-config-prettier": "^10.1.8",
         "eslint-plugin-security": "^4.0.0",
         "globals": "^17.4.0",
         "jest": "^30.3.0",
         "prettier": "^3.8.1",
-        "ts-jest": "^29.4.6",
+        "ts-jest": "^29.4.9",
         "ts-node": "^10.9.2",
         "typedoc": "^0.28.18",
-        "typescript": "^5.9.3",
-        "typescript-eslint": "^8.57.1"
+        "typescript": "^6.0.2",
+        "typescript-eslint": "^8.58.0"
       },
       "engines": {
         "node": ">=24.0.0"
@@ -638,13 +638,13 @@
       }
     },
     "node_modules/@eslint/config-array": {
-      "version": "0.23.3",
-      "resolved": "https://registry.npmjs.org/@eslint/config-array/-/config-array-0.23.3.tgz",
-      "integrity": "sha512-j+eEWmB6YYLwcNOdlwQ6L2OsptI/LO6lNBuLIqe5R7RetD658HLoF+Mn7LzYmAWWNNzdC6cqP+L6r8ujeYXWLw==",
+      "version": "0.23.4",
+      "resolved": "https://registry.npmjs.org/@eslint/config-array/-/config-array-0.23.4.tgz",
+      "integrity": "sha512-lf19F24LSMfF8weXvW5QEtnLqW70u7kgit5e9PSx0MsHAFclGd1T9ynvWEMDT1w5J4Qt54tomGeAhdoAku1Xow==",
       "dev": true,
       "license": "Apache-2.0",
       "dependencies": {
-        "@eslint/object-schema": "^3.0.3",
+        "@eslint/object-schema": "^3.0.4",
         "debug": "^4.3.1",
         "minimatch": "^10.2.4"
       },
@@ -676,13 +676,13 @@
       }
     },
     "node_modules/@eslint/config-array/node_modules/minimatch": {
-      "version": "10.2.4",
-      "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-10.2.4.tgz",
-      "integrity": "sha512-oRjTw/97aTBN0RHbYCdtF1MQfvusSIBQM0IZEgzl6426+8jSC0nF1a/GmnVLpfB9yyr6g6FTqWqiZVbxrtaCIg==",
+      "version": "10.2.5",
+      "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-10.2.5.tgz",
+      "integrity": "sha512-MULkVLfKGYDFYejP07QOurDLLQpcjk7Fw+7jXS2R2czRQzR56yHRveU5NDJEOviH+hETZKSkIk5c+T23GjFUMg==",
       "dev": true,
       "license": "BlueOak-1.0.0",
       "dependencies": {
-        "brace-expansion": "^5.0.2"
+        "brace-expansion": "^5.0.5"
       },
       "engines": {
         "node": "18 || 20 || >=22"
@@ -692,22 +692,22 @@
       }
     },
     "node_modules/@eslint/config-helpers": {
-      "version": "0.5.3",
-      "resolved": "https://registry.npmjs.org/@eslint/config-helpers/-/config-helpers-0.5.3.tgz",
-      "integrity": "sha512-lzGN0onllOZCGroKJmRwY6QcEHxbjBw1gwB8SgRSqK8YbbtEXMvKynsXc3553ckIEBxsbMBU7oOZXKIPGZNeZw==",
+      "version": "0.5.4",
+      "resolved": "https://registry.npmjs.org/@eslint/config-helpers/-/config-helpers-0.5.4.tgz",
+      "integrity": "sha512-jJhqiY3wPMlWWO3370M86CPJ7pt8GmEwSLglMfQhjXal07RCvhmU0as4IuUEW5SJeunfItiEetHmSxCCe9lDBg==",
       "dev": true,
       "license": "Apache-2.0",
       "dependencies": {
-        "@eslint/core": "^1.1.1"
+        "@eslint/core": "^1.2.0"
       },
       "engines": {
         "node": "^20.19.0 || ^22.13.0 || >=24"
       }
     },
     "node_modules/@eslint/core": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/@eslint/core/-/core-1.1.1.tgz",
-      "integrity": "sha512-QUPblTtE51/7/Zhfv8BDwO0qkkzQL7P/aWWbqcf4xWLEYn1oKjdO0gglQBB4GAsu7u6wjijbCmzsUTy6mnk6oQ==",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/@eslint/core/-/core-1.2.0.tgz",
+      "integrity": "sha512-8FTGbNzTvmSlc4cZBaShkC6YvFMG0riksYWRFKXztqVdXaQbcZLXlFbSpC05s70sGEsXAw0qwhx69JiW7hQS7A==",
       "dev": true,
       "license": "Apache-2.0",
       "dependencies": {
@@ -755,9 +755,9 @@
       }
     },
     "node_modules/@eslint/object-schema": {
-      "version": "3.0.3",
-      "resolved": "https://registry.npmjs.org/@eslint/object-schema/-/object-schema-3.0.3.tgz",
-      "integrity": "sha512-iM869Pugn9Nsxbh/YHRqYiqd23AmIbxJOcpUMOuWCVNdoQJ5ZtwL6h3t0bcZzJUlC3Dq9jCFCESBZnX0GTv7iQ==",
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/@eslint/object-schema/-/object-schema-3.0.4.tgz",
+      "integrity": "sha512-55lO/7+Yp0ISKRP0PsPtNTeNGapXaO085aELZmWCVc5SH3jfrqpuU6YgOdIxMS99ZHkQN1cXKE+cdIqwww9ptw==",
       "dev": true,
       "license": "Apache-2.0",
       "engines": {
@@ -1574,9 +1574,9 @@
       "license": "MIT"
     },
     "node_modules/@types/node": {
-      "version": "25.5.0",
-      "resolved": "https://registry.npmjs.org/@types/node/-/node-25.5.0.tgz",
-      "integrity": "sha512-jp2P3tQMSxWugkCUKLRPVUpGaL5MVFwF8RDuSRztfwgN1wmqJeMSbKlnEtQqU8UrhTmzEmZdu2I6v2dpp7XIxw==",
+      "version": "25.5.2",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-25.5.2.tgz",
+      "integrity": "sha512-tO4ZIRKNC+MDWV4qKVZe3Ql/woTnmHDr5JD8UI5hn2pwBrHEwOEMZK7WlNb5RKB6EoJ02gwmQS9OrjuFnZYdpg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -1615,20 +1615,20 @@
       "license": "MIT"
     },
     "node_modules/@typescript-eslint/eslint-plugin": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-8.57.1.tgz",
-      "integrity": "sha512-Gn3aqnvNl4NGc6x3/Bqk1AOn0thyTU9bqDRhiRnUWezgvr2OnhYCWCgC8zXXRVqBsIL1pSDt7T9nJUe0oM0kDQ==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-8.58.0.tgz",
+      "integrity": "sha512-RLkVSiNuUP1C2ROIWfqX+YcUfLaSnxGE/8M+Y57lopVwg9VTYYfhuz15Yf1IzCKgZj6/rIbYTmJCUSqr76r0Wg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
         "@eslint-community/regexpp": "^4.12.2",
-        "@typescript-eslint/scope-manager": "8.57.1",
-        "@typescript-eslint/type-utils": "8.57.1",
-        "@typescript-eslint/utils": "8.57.1",
-        "@typescript-eslint/visitor-keys": "8.57.1",
+        "@typescript-eslint/scope-manager": "8.58.0",
+        "@typescript-eslint/type-utils": "8.58.0",
+        "@typescript-eslint/utils": "8.58.0",
+        "@typescript-eslint/visitor-keys": "8.58.0",
         "ignore": "^7.0.5",
         "natural-compare": "^1.4.0",
-        "ts-api-utils": "^2.4.0"
+        "ts-api-utils": "^2.5.0"
       },
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -1638,9 +1638,9 @@
         "url": "https://opencollective.com/typescript-eslint"
       },
       "peerDependencies": {
-        "@typescript-eslint/parser": "^8.57.1",
+        "@typescript-eslint/parser": "^8.58.0",
         "eslint": "^8.57.0 || ^9.0.0 || ^10.0.0",
-        "typescript": ">=4.8.4 <6.0.0"
+        "typescript": ">=4.8.4 <6.1.0"
       }
     },
     "node_modules/@typescript-eslint/eslint-plugin/node_modules/ignore": {
@@ -1654,16 +1654,16 @@
       }
     },
     "node_modules/@typescript-eslint/parser": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/parser/-/parser-8.57.1.tgz",
-      "integrity": "sha512-k4eNDan0EIMTT/dUKc/g+rsJ6wcHYhNPdY19VoX/EOtaAG8DLtKCykhrUnuHPYvinn5jhAPgD2Qw9hXBwrahsw==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/parser/-/parser-8.58.0.tgz",
+      "integrity": "sha512-rLoGZIf9afaRBYsPUMtvkDWykwXwUPL60HebR4JgTI8mxfFe2cQTu3AGitANp4b9B2QlVru6WzjgB2IzJKiCSA==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/scope-manager": "8.57.1",
-        "@typescript-eslint/types": "8.57.1",
-        "@typescript-eslint/typescript-estree": "8.57.1",
-        "@typescript-eslint/visitor-keys": "8.57.1",
+        "@typescript-eslint/scope-manager": "8.58.0",
+        "@typescript-eslint/types": "8.58.0",
+        "@typescript-eslint/typescript-estree": "8.58.0",
+        "@typescript-eslint/visitor-keys": "8.58.0",
         "debug": "^4.4.3"
       },
       "engines": {
@@ -1675,18 +1675,18 @@
       },
       "peerDependencies": {
         "eslint": "^8.57.0 || ^9.0.0 || ^10.0.0",
-        "typescript": ">=4.8.4 <6.0.0"
+        "typescript": ">=4.8.4 <6.1.0"
       }
     },
     "node_modules/@typescript-eslint/project-service": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/project-service/-/project-service-8.57.1.tgz",
-      "integrity": "sha512-vx1F37BRO1OftsYlmG9xay1TqnjNVlqALymwWVuYTdo18XuKxtBpCj1QlzNIEHlvlB27osvXFWptYiEWsVdYsg==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/project-service/-/project-service-8.58.0.tgz",
+      "integrity": "sha512-8Q/wBPWLQP1j16NxoPNIKpDZFMaxl7yWIoqXWYeWO+Bbd2mjgvoF0dxP2jKZg5+x49rgKdf7Ck473M8PC3V9lg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/tsconfig-utils": "^8.57.1",
-        "@typescript-eslint/types": "^8.57.1",
+        "@typescript-eslint/tsconfig-utils": "^8.58.0",
+        "@typescript-eslint/types": "^8.58.0",
         "debug": "^4.4.3"
       },
       "engines": {
@@ -1697,18 +1697,18 @@
         "url": "https://opencollective.com/typescript-eslint"
       },
       "peerDependencies": {
-        "typescript": ">=4.8.4 <6.0.0"
+        "typescript": ">=4.8.4 <6.1.0"
       }
     },
     "node_modules/@typescript-eslint/scope-manager": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/scope-manager/-/scope-manager-8.57.1.tgz",
-      "integrity": "sha512-hs/QcpCwlwT2L5S+3fT6gp0PabyGk4Q0Rv2doJXA0435/OpnSR3VRgvrp8Xdoc3UAYSg9cyUjTeFXZEPg/3OKg==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/scope-manager/-/scope-manager-8.58.0.tgz",
+      "integrity": "sha512-W1Lur1oF50FxSnNdGp3Vs6P+yBRSmZiw4IIjEeYxd8UQJwhUF0gDgDD/W/Tgmh73mxgEU3qX0Bzdl/NGuSPEpQ==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/types": "8.57.1",
-        "@typescript-eslint/visitor-keys": "8.57.1"
+        "@typescript-eslint/types": "8.58.0",
+        "@typescript-eslint/visitor-keys": "8.58.0"
       },
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -1719,9 +1719,9 @@
       }
     },
     "node_modules/@typescript-eslint/tsconfig-utils": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/tsconfig-utils/-/tsconfig-utils-8.57.1.tgz",
-      "integrity": "sha512-0lgOZB8cl19fHO4eI46YUx2EceQqhgkPSuCGLlGi79L2jwYY1cxeYc1Nae8Aw1xjgW3PKVDLlr3YJ6Bxx8HkWg==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/tsconfig-utils/-/tsconfig-utils-8.58.0.tgz",
+      "integrity": "sha512-doNSZEVJsWEu4htiVC+PR6NpM+pa+a4ClH9INRWOWCUzMst/VA9c4gXq92F8GUD1rwhNvRLkgjfYtFXegXQF7A==",
       "dev": true,
       "license": "MIT",
       "engines": {
@@ -1732,21 +1732,21 @@
         "url": "https://opencollective.com/typescript-eslint"
       },
       "peerDependencies": {
-        "typescript": ">=4.8.4 <6.0.0"
+        "typescript": ">=4.8.4 <6.1.0"
       }
     },
     "node_modules/@typescript-eslint/type-utils": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/type-utils/-/type-utils-8.57.1.tgz",
-      "integrity": "sha512-+Bwwm0ScukFdyoJsh2u6pp4S9ktegF98pYUU0hkphOOqdMB+1sNQhIz8y5E9+4pOioZijrkfNO/HUJVAFFfPKA==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/type-utils/-/type-utils-8.58.0.tgz",
+      "integrity": "sha512-aGsCQImkDIqMyx1u4PrVlbi/krmDsQUs4zAcCV6M7yPcPev+RqVlndsJy9kJ8TLihW9TZ0kbDAzctpLn5o+lOg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/types": "8.57.1",
-        "@typescript-eslint/typescript-estree": "8.57.1",
-        "@typescript-eslint/utils": "8.57.1",
+        "@typescript-eslint/types": "8.58.0",
+        "@typescript-eslint/typescript-estree": "8.58.0",
+        "@typescript-eslint/utils": "8.58.0",
         "debug": "^4.4.3",
-        "ts-api-utils": "^2.4.0"
+        "ts-api-utils": "^2.5.0"
       },
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -1757,13 +1757,13 @@
       },
       "peerDependencies": {
         "eslint": "^8.57.0 || ^9.0.0 || ^10.0.0",
-        "typescript": ">=4.8.4 <6.0.0"
+        "typescript": ">=4.8.4 <6.1.0"
       }
     },
     "node_modules/@typescript-eslint/types": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/types/-/types-8.57.1.tgz",
-      "integrity": "sha512-S29BOBPJSFUiblEl6RzPPjJt6w25A6XsBqRVDt53tA/tlL8q7ceQNZHTjPeONt/3S7KRI4quk+yP9jK2WjBiPQ==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/types/-/types-8.58.0.tgz",
+      "integrity": "sha512-O9CjxypDT89fbHxRfETNoAnHj/i6IpRK0CvbVN3qibxlLdo5p5hcLmUuCCrHMpxiWSwKyI8mCP7qRNYuOJ0Uww==",
       "dev": true,
       "license": "MIT",
       "engines": {
@@ -1775,21 +1775,21 @@
       }
     },
     "node_modules/@typescript-eslint/typescript-estree": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/typescript-estree/-/typescript-estree-8.57.1.tgz",
-      "integrity": "sha512-ybe2hS9G6pXpqGtPli9Gx9quNV0TWLOmh58ADlmZe9DguLq0tiAKVjirSbtM1szG6+QH6rVXyU6GTLQbWnMY+g==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/typescript-estree/-/typescript-estree-8.58.0.tgz",
+      "integrity": "sha512-7vv5UWbHqew/dvs+D3e1RvLv1v2eeZ9txRHPnEEBUgSNLx5ghdzjHa0sgLWYVKssH+lYmV0JaWdoubo0ncGYLA==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/project-service": "8.57.1",
-        "@typescript-eslint/tsconfig-utils": "8.57.1",
-        "@typescript-eslint/types": "8.57.1",
-        "@typescript-eslint/visitor-keys": "8.57.1",
+        "@typescript-eslint/project-service": "8.58.0",
+        "@typescript-eslint/tsconfig-utils": "8.58.0",
+        "@typescript-eslint/types": "8.58.0",
+        "@typescript-eslint/visitor-keys": "8.58.0",
         "debug": "^4.4.3",
         "minimatch": "^10.2.2",
         "semver": "^7.7.3",
         "tinyglobby": "^0.2.15",
-        "ts-api-utils": "^2.4.0"
+        "ts-api-utils": "^2.5.0"
       },
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -1799,7 +1799,7 @@
         "url": "https://opencollective.com/typescript-eslint"
       },
       "peerDependencies": {
-        "typescript": ">=4.8.4 <6.0.0"
+        "typescript": ">=4.8.4 <6.1.0"
       }
     },
     "node_modules/@typescript-eslint/typescript-estree/node_modules/balanced-match": {
@@ -1826,13 +1826,13 @@
       }
     },
     "node_modules/@typescript-eslint/typescript-estree/node_modules/minimatch": {
-      "version": "10.2.4",
-      "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-10.2.4.tgz",
-      "integrity": "sha512-oRjTw/97aTBN0RHbYCdtF1MQfvusSIBQM0IZEgzl6426+8jSC0nF1a/GmnVLpfB9yyr6g6FTqWqiZVbxrtaCIg==",
+      "version": "10.2.5",
+      "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-10.2.5.tgz",
+      "integrity": "sha512-MULkVLfKGYDFYejP07QOurDLLQpcjk7Fw+7jXS2R2czRQzR56yHRveU5NDJEOviH+hETZKSkIk5c+T23GjFUMg==",
       "dev": true,
       "license": "BlueOak-1.0.0",
       "dependencies": {
-        "brace-expansion": "^5.0.2"
+        "brace-expansion": "^5.0.5"
       },
       "engines": {
         "node": "18 || 20 || >=22"
@@ -1855,16 +1855,16 @@
       }
     },
     "node_modules/@typescript-eslint/utils": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/utils/-/utils-8.57.1.tgz",
-      "integrity": "sha512-XUNSJ/lEVFttPMMoDVA2r2bwrl8/oPx8cURtczkSEswY5T3AeLmCy+EKWQNdL4u0MmAHOjcWrqJp2cdvgjn8dQ==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/utils/-/utils-8.58.0.tgz",
+      "integrity": "sha512-RfeSqcFeHMHlAWzt4TBjWOAtoW9lnsAGiP3GbaX9uVgTYYrMbVnGONEfUCiSss+xMHFl+eHZiipmA8WkQ7FuNA==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
         "@eslint-community/eslint-utils": "^4.9.1",
-        "@typescript-eslint/scope-manager": "8.57.1",
-        "@typescript-eslint/types": "8.57.1",
-        "@typescript-eslint/typescript-estree": "8.57.1"
+        "@typescript-eslint/scope-manager": "8.58.0",
+        "@typescript-eslint/types": "8.58.0",
+        "@typescript-eslint/typescript-estree": "8.58.0"
       },
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -1875,17 +1875,17 @@
       },
       "peerDependencies": {
         "eslint": "^8.57.0 || ^9.0.0 || ^10.0.0",
-        "typescript": ">=4.8.4 <6.0.0"
+        "typescript": ">=4.8.4 <6.1.0"
       }
     },
     "node_modules/@typescript-eslint/visitor-keys": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/visitor-keys/-/visitor-keys-8.57.1.tgz",
-      "integrity": "sha512-YWnmJkXbofiz9KbnbbwuA2rpGkFPLbAIetcCNO6mJ8gdhdZ/v7WDXsoGFAJuM6ikUFKTlSQnjWnVO4ux+UzS6A==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/visitor-keys/-/visitor-keys-8.58.0.tgz",
+      "integrity": "sha512-XJ9UD9+bbDo4a4epraTwG3TsNPeiB9aShrUneAVXy8q4LuwowN+qu89/6ByLMINqvIMeI9H9hOHQtg/ijrYXzQ==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/types": "8.57.1",
+        "@typescript-eslint/types": "8.58.0",
         "eslint-visitor-keys": "^5.0.0"
       },
       "engines": {
@@ -2900,18 +2900,18 @@
       }
     },
     "node_modules/eslint": {
-      "version": "10.1.0",
-      "resolved": "https://registry.npmjs.org/eslint/-/eslint-10.1.0.tgz",
-      "integrity": "sha512-S9jlY/ELKEUwwQnqWDO+f+m6sercqOPSqXM5Go94l7DOmxHVDgmSFGWEzeE/gwgTAr0W103BWt0QLe/7mabIvA==",
+      "version": "10.2.0",
+      "resolved": "https://registry.npmjs.org/eslint/-/eslint-10.2.0.tgz",
+      "integrity": "sha512-+L0vBFYGIpSNIt/KWTpFonPrqYvgKw1eUI5Vn7mEogrQcWtWYtNQ7dNqC+px/J0idT3BAkiWrhfS7k+Tum8TUA==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
         "@eslint-community/eslint-utils": "^4.8.0",
         "@eslint-community/regexpp": "^4.12.2",
-        "@eslint/config-array": "^0.23.3",
-        "@eslint/config-helpers": "^0.5.3",
-        "@eslint/core": "^1.1.1",
-        "@eslint/plugin-kit": "^0.6.1",
+        "@eslint/config-array": "^0.23.4",
+        "@eslint/config-helpers": "^0.5.4",
+        "@eslint/core": "^1.2.0",
+        "@eslint/plugin-kit": "^0.7.0",
         "@humanfs/node": "^0.16.6",
         "@humanwhocodes/module-importer": "^1.0.1",
         "@humanwhocodes/retry": "^0.4.2",
@@ -3019,6 +3019,20 @@
         "url": "https://opencollective.com/eslint"
       }
     },
+    "node_modules/eslint/node_modules/@eslint/plugin-kit": {
+      "version": "0.7.0",
+      "resolved": "https://registry.npmjs.org/@eslint/plugin-kit/-/plugin-kit-0.7.0.tgz",
+      "integrity": "sha512-ejvBr8MQCbVsWNZnCwDXjUKq40MDmHalq7cJ6e9s/qzTUFIIo/afzt1Vui9T97FM/V/pN4YsFVoed5NIa96RDg==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "dependencies": {
+        "@eslint/core": "^1.2.0",
+        "levn": "^0.4.1"
+      },
+      "engines": {
+        "node": "^20.19.0 || ^22.13.0 || >=24"
+      }
+    },
     "node_modules/eslint/node_modules/ajv": {
       "version": "6.14.0",
       "resolved": "https://registry.npmjs.org/ajv/-/ajv-6.14.0.tgz",
@@ -5764,19 +5778,19 @@
       }
     },
     "node_modules/ts-jest": {
-      "version": "29.4.6",
-      "resolved": "https://registry.npmjs.org/ts-jest/-/ts-jest-29.4.6.tgz",
-      "integrity": "sha512-fSpWtOO/1AjSNQguk43hb/JCo16oJDnMJf3CdEGNkqsEX3t0KX96xvyX1D7PfLCpVoKu4MfVrqUkFyblYoY4lA==",
+      "version": "29.4.9",
+      "resolved": "https://registry.npmjs.org/ts-jest/-/ts-jest-29.4.9.tgz",
+      "integrity": "sha512-LTb9496gYPMCqjeDLdPrKuXtncudeV1yRZnF4Wo5l3SFi0RYEnYRNgMrFIdg+FHvfzjCyQk1cLncWVqiSX+EvQ==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
         "bs-logger": "^0.2.6",
         "fast-json-stable-stringify": "^2.1.0",
-        "handlebars": "^4.7.8",
+        "handlebars": "^4.7.9",
         "json5": "^2.2.3",
         "lodash.memoize": "^4.1.2",
         "make-error": "^1.3.6",
-        "semver": "^7.7.3",
+        "semver": "^7.7.4",
         "type-fest": "^4.41.0",
         "yargs-parser": "^21.1.1"
       },
@@ -5793,7 +5807,7 @@
         "babel-jest": "^29.0.0 || ^30.0.0",
         "jest": "^29.0.0 || ^30.0.0",
         "jest-util": "^29.0.0 || ^30.0.0",
-        "typescript": ">=4.3 <6"
+        "typescript": ">=4.3 <7"
       },
       "peerDependenciesMeta": {
         "@babel/core": {
@@ -5994,9 +6008,9 @@
       }
     },
     "node_modules/typescript": {
-      "version": "5.9.3",
-      "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.9.3.tgz",
-      "integrity": "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw==",
+      "version": "6.0.2",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-6.0.2.tgz",
+      "integrity": "sha512-bGdAIrZ0wiGDo5l8c++HWtbaNCWTS4UTv7RaTH/ThVIgjkveJt83m74bBHMJkuCbslY8ixgLBVZJIOiQlQTjfQ==",
       "dev": true,
       "license": "Apache-2.0",
       "bin": {
@@ -6008,16 +6022,16 @@
       }
     },
     "node_modules/typescript-eslint": {
-      "version": "8.57.1",
-      "resolved": "https://registry.npmjs.org/typescript-eslint/-/typescript-eslint-8.57.1.tgz",
-      "integrity": "sha512-fLvZWf+cAGw3tqMCYzGIU6yR8K+Y9NT2z23RwOjlNFF2HwSB3KhdEFI5lSBv8tNmFkkBShSjsCjzx1vahZfISA==",
+      "version": "8.58.0",
+      "resolved": "https://registry.npmjs.org/typescript-eslint/-/typescript-eslint-8.58.0.tgz",
+      "integrity": "sha512-e2TQzKfaI85fO+F3QywtX+tCTsu/D3WW5LVU6nz8hTFKFZ8yBJ6mSYRpXqdR3mFjPWmO0eWsTa5f+UpAOe/FMA==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/eslint-plugin": "8.57.1",
-        "@typescript-eslint/parser": "8.57.1",
-        "@typescript-eslint/typescript-estree": "8.57.1",
-        "@typescript-eslint/utils": "8.57.1"
+        "@typescript-eslint/eslint-plugin": "8.58.0",
+        "@typescript-eslint/parser": "8.58.0",
+        "@typescript-eslint/typescript-estree": "8.58.0",
+        "@typescript-eslint/utils": "8.58.0"
       },
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -6028,7 +6042,7 @@
       },
       "peerDependencies": {
         "eslint": "^8.57.0 || ^9.0.0 || ^10.0.0",
-        "typescript": ">=4.8.4 <6.0.0"
+        "typescript": ">=4.8.4 <6.1.0"
       }
     },
     "node_modules/uc.micro": {
diff --git a/package.json b/package.json
index 62c718e..731c945 100644
--- a/package.json
+++ b/package.json
@@ -58,17 +58,17 @@
     "@eslint/js": "^10.0.1",
     "@eslint/json": "^1.2.0",
     "@types/jest": "^30.0.0",
-    "@types/node": "^25.5.0",
-    "eslint": "^10.1.0",
+    "@types/node": "^25.5.2",
+    "eslint": "^10.2.0",
     "eslint-config-prettier": "^10.1.8",
     "eslint-plugin-security": "^4.0.0",
     "globals": "^17.4.0",
     "jest": "^30.3.0",
     "prettier": "^3.8.1",
-    "ts-jest": "^29.4.6",
+    "ts-jest": "^29.4.9",
     "ts-node": "^10.9.2",
     "typedoc": "^0.28.18",
-    "typescript": "^5.9.3",
-    "typescript-eslint": "^8.57.1"
+    "typescript": "^6.0.2",
+    "typescript-eslint": "^8.58.0"
   }
 }

From b732ce6ae7c1da67ec4aba974c217eafa041107f Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Sun, 5 Apr 2026 23:55:55 +0200
Subject: [PATCH 06/11] fix: Address review comments

---
 eslint.config.cjs          |  8 ++++++++
 src/adapters/git.ts        |  1 +
 src/core/filesystem.ts     |  5 +++++
 tests/adapters.git.test.ts | 12 ++----------
 tests/describe.test.ts     |  4 +++-
 5 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/eslint.config.cjs b/eslint.config.cjs
index 0ae33c7..0967761 100644
--- a/eslint.config.cjs
+++ b/eslint.config.cjs
@@ -36,6 +36,14 @@ module.exports = [
               name: 'node:fs/promises',
               message: FILESYSTEM_IMPORT_MESSAGE,
             },
+            {
+              name: 'fs',
+              message: FILESYSTEM_IMPORT_MESSAGE,
+            },
+            {
+              name: 'fs/promises',
+              message: FILESYSTEM_IMPORT_MESSAGE,
+            },
           ],
         },
       ],
diff --git a/src/adapters/git.ts b/src/adapters/git.ts
index ccb9a9d..d7cfd21 100644
--- a/src/adapters/git.ts
+++ b/src/adapters/git.ts
@@ -94,6 +94,7 @@ export class ExecaGitClient implements GitClient {
   async exportPath(repoPath: string, commit: string, destination: string, subPath?: string): Promise<void> {
     assertSafeGitArg(repoPath, 'repository path');
     assertSafeGitArg(destination, 'destination path');
+    resolveSafeSubPath(repoPath, subPath);
     if (!COMMIT_SHA_PATTERN.test(commit)) {
       throw new SkillInstallError(`Invalid commit SHA: ${commit}`);
     }
diff --git a/src/core/filesystem.ts b/src/core/filesystem.ts
index 6710a58..6ab623a 100644
--- a/src/core/filesystem.ts
+++ b/src/core/filesystem.ts
@@ -30,6 +30,11 @@ export class NodeFileSystem implements FileSystem {
     await fs.mkdir(target, { recursive: true });
   }
 
+  /**
+   * Creates a new temporary directory.
+   * @param prefix Prefix used for the temporary directory name.
+   * @returns Promise resolving to the created directory path.
+   */
   async mkdtemp(prefix: string): Promise<string> {
     return fs.mkdtemp(prefix);
   }
diff --git a/tests/adapters.git.test.ts b/tests/adapters.git.test.ts
index 1426163..019daa8 100644
--- a/tests/adapters.git.test.ts
+++ b/tests/adapters.git.test.ts
@@ -86,15 +86,7 @@ describe('ExecaGitClient security hardening', () => {
       'Invalid skill path ../escape',
     );
 
-    expect(mockedExeca).toHaveBeenCalledWith(
-      'git',
-      ['-C', '/tmp/cache/repo', 'worktree', 'add', '--force', '--detach', '/tmp/skilleton-wt-123', commit],
-      expect.any(Object),
-    );
-    expect(mockedExeca).toHaveBeenCalledWith(
-      'git',
-      ['-C', '/tmp/cache/repo', 'worktree', 'remove', '--force', '/tmp/skilleton-wt-123'],
-      expect.any(Object),
-    );
+    expect(mockedFs.mkdtemp).not.toHaveBeenCalled();
+    expect(mockedExeca).not.toHaveBeenCalled();
   });
 });
diff --git a/tests/describe.test.ts b/tests/describe.test.ts
index 35e29bb..44b7290 100644
--- a/tests/describe.test.ts
+++ b/tests/describe.test.ts
@@ -248,6 +248,7 @@ function createThrowingProxy(name: string): ProxyHandler<object> {
 class InMemoryFileSystem implements FileSystem {
   private directories = new Set<string>();
   private files = new Map<string, string>();
+  private tempCounter = 0;
 
   constructor() {
     this.directories.add('/');
@@ -275,7 +276,8 @@ class InMemoryFileSystem implements FileSystem {
   }
 
   async mkdtemp(prefix: string): Promise<string> {
-    const tempDir = this.normalize(`${prefix}tmp`);
+    this.tempCounter += 1;
+    const tempDir = this.normalize(`${prefix}tmp-${this.tempCounter}`);
     this.directories.add(tempDir);
     return tempDir;
   }

From 2d494ed7919059051154fa257bc4e0a09cc36e87 Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Mon, 6 Apr 2026 00:00:32 +0200
Subject: [PATCH 07/11] refactor: extract MockedFileSystem to shared helper and
 improve coverage config

- Move InMemoryFileSystem from describe.test.ts to tests/helpers/mocked-filesystem.ts
- Rename InMemoryFileSystem to MockedFileSystem with jest.fn() methods
- Add createMockedFileSystem() factory function
- Update all tests to use shared MockedFileSystem helper
- Implement missing FileSystem methods (readJson, writeJson, remove, copy, symlink)
- Configure Jest to collect coverage from src/**/*.ts files only
---
 jest.config.cjs                    |   1 +
 tests/adapters.git.test.ts         |  20 +---
 tests/describe.test.ts             | 123 +---------------------
 tests/helpers/mocked-filesystem.ts | 162 +++++++++++++++++++++++++++++
 tests/install.test.ts              |  17 +--
 5 files changed, 173 insertions(+), 150 deletions(-)
 create mode 100644 tests/helpers/mocked-filesystem.ts

diff --git a/jest.config.cjs b/jest.config.cjs
index 84b4296..f750b30 100644
--- a/jest.config.cjs
+++ b/jest.config.cjs
@@ -9,6 +9,7 @@ const config = {
     '^.+\\.(ts|tsx)$': 'ts-jest',
   },
   collectCoverage: true,
+  collectCoverageFrom: ['src/**/*.ts'],
 };
 
 module.exports = config;
diff --git a/tests/adapters.git.test.ts b/tests/adapters.git.test.ts
index 019daa8..e2bb7c6 100644
--- a/tests/adapters.git.test.ts
+++ b/tests/adapters.git.test.ts
@@ -1,31 +1,17 @@
 import { execa } from 'execa';
 import { ExecaGitClient } from '../src/adapters/git';
 import { SkillInstallError } from '../src/core/errors';
-import { FileSystem } from '../src/core/types';
+import { MockedFileSystem, createMockedFileSystem } from './helpers/mocked-filesystem';
 
 jest.mock('execa');
 
-const createFsMock = (): jest.Mocked<FileSystem> => ({
-  pathExists: jest.fn(),
-  ensureDir: jest.fn(),
-  mkdtemp: jest.fn(),
-  readJson: jest.fn(),
-  writeJson: jest.fn(),
-  readFile: jest.fn(),
-  isDirectory: jest.fn(),
-  remove: jest.fn(),
-  copy: jest.fn(),
-  symlink: jest.fn(),
-  readDir: jest.fn(),
-});
-
 describe('ExecaGitClient security hardening', () => {
-  let mockedFs: jest.Mocked<FileSystem>;
+  let mockedFs: MockedFileSystem;
   const mockedExeca = execa as unknown as jest.Mock;
 
   beforeEach(() => {
     jest.clearAllMocks();
-    mockedFs = createFsMock();
+    mockedFs = createMockedFileSystem();
     mockedFs.pathExists.mockResolvedValue(true);
     mockedFs.ensureDir.mockResolvedValue(undefined);
     mockedFs.remove.mockResolvedValue(undefined);
diff --git a/tests/describe.test.ts b/tests/describe.test.ts
index 44b7290..2b6d837 100644
--- a/tests/describe.test.ts
+++ b/tests/describe.test.ts
@@ -3,6 +3,7 @@ import { DescribeCommand } from '../src/commands/describe';
 import { SkilletonEnvironment } from '../src/env';
 import { FileSystem, SkillLockfile, SkillManifest } from '../src/core/types';
 import { ManifestNotFoundError } from '../src/core/errors';
+import { createMockedFileSystem } from './helpers/mocked-filesystem';
 
 describe('DescribeCommand', () => {
   let consoleLogSpy: jest.SpyInstance;
@@ -85,7 +86,7 @@ describe('DescribeCommand', () => {
       ],
     };
 
-    const fs = new InMemoryFileSystem();
+    const fs = createMockedFileSystem();
     fs.addDirectory(installPath);
     fs.addDirectory(path.join(installPath, 'rules'));
     fs.addFile(
@@ -131,7 +132,7 @@ describe('DescribeCommand', () => {
       ],
     };
 
-    const fs = new InMemoryFileSystem();
+    const fs = createMockedFileSystem();
     fs.addDirectory(installPath);
     fs.addFile(path.join(installPath, 'README.md'), '# Readme');
     const env = createEnv({ manifest, installPaths: { [skillName]: installPath }, fileSystem: fs });
@@ -158,7 +159,7 @@ describe('DescribeCommand', () => {
       ],
     };
 
-    const fs = new InMemoryFileSystem();
+    const fs = createMockedFileSystem();
     fs.addDirectory(installPath);
     fs.addFile(path.join(installPath, 'SKILL.md'), '# Hello world');
     const env = createEnv({ manifest, installPaths: { [skillName]: installPath }, fileSystem: fs });
@@ -193,7 +194,7 @@ function createEnv(options: CreateEnvOptions = {}): SkilletonEnvironment {
     options.manifest ?? ({ $schema: './skilleton.schema.json', skills: [] } as SkillManifest);
   const lockfile = options.lockfile ?? null;
   const installPaths = options.installPaths ?? {};
-  const fs = options.fileSystem ?? new InMemoryFileSystem();
+  const fs = options.fileSystem ?? createMockedFileSystem();
   const manifestError = options.manifestError ?? null;
 
   const manifestRepo = {
@@ -244,117 +245,3 @@ function createThrowingProxy(name: string): ProxyHandler<object> {
     },
   );
 }
-
-class InMemoryFileSystem implements FileSystem {
-  private directories = new Set<string>();
-  private files = new Map<string, string>();
-  private tempCounter = 0;
-
-  constructor() {
-    this.directories.add('/');
-  }
-
-  addDirectory(dir: string): void {
-    const normalized = this.normalize(dir);
-    this.directories.add(normalized);
-  }
-
-  addFile(target: string, content: string): void {
-    const normalized = this.normalize(target);
-    const dir = path.dirname(normalized);
-    this.directories.add(dir);
-    this.files.set(normalized, content);
-  }
-
-  async pathExists(target: string): Promise<boolean> {
-    const normalized = this.normalize(target);
-    return this.directories.has(normalized) || this.files.has(normalized);
-  }
-
-  async ensureDir(target: string): Promise<void> {
-    this.directories.add(this.normalize(target));
-  }
-
-  async mkdtemp(prefix: string): Promise<string> {
-    this.tempCounter += 1;
-    const tempDir = this.normalize(`${prefix}tmp-${this.tempCounter}`);
-    this.directories.add(tempDir);
-    return tempDir;
-  }
-
-  async readJson<T>(_path: string): Promise<T> {
-    throw new Error('Not implemented');
-  }
-
-  async writeJson(_path: string, _data: unknown): Promise<void> {
-    throw new Error('Not implemented');
-  }
-
-  async readFile(target: string): Promise<string> {
-    const normalized = this.normalize(target);
-    const content = this.files.get(normalized);
-    if (content === undefined) {
-      throw new Error(`File not found: ${target}`);
-    }
-    return content;
-  }
-
-  async isDirectory(target: string): Promise<boolean> {
-    return this.directories.has(this.normalize(target));
-  }
-
-  async remove(_path: string): Promise<void> {
-    throw new Error('Not implemented');
-  }
-
-  async copy(_src: string, _dest: string): Promise<void> {
-    throw new Error('Not implemented');
-  }
-
-  async symlink(_target: string, _path: string): Promise<void> {
-    throw new Error('Not implemented');
-  }
-
-  async readDir(target: string): Promise<string[]> {
-    const normalized = this.normalize(target);
-    const entries = new Set<string>();
-    const prefix = normalized.endsWith('/') ? normalized : `${normalized}/`;
-
-    for (const dir of this.directories) {
-      if (dir === normalized) {
-        continue;
-      }
-      if (!dir.startsWith(prefix)) {
-        continue;
-      }
-      const relative = dir.slice(prefix.length);
-      if (relative.length === 0) {
-        continue;
-      }
-      const segment = relative.split('/')[0];
-      entries.add(segment);
-    }
-
-    for (const filePath of this.files.keys()) {
-      if (!filePath.startsWith(prefix)) {
-        continue;
-      }
-      const relative = filePath.slice(prefix.length);
-      if (relative.length === 0) {
-        continue;
-      }
-      const segment = relative.split('/')[0];
-      entries.add(segment);
-    }
-
-    if (!this.directories.has(normalized) && entries.size === 0) {
-      throw new Error(`Directory not found: ${target}`);
-    }
-
-    return Array.from(entries);
-  }
-
-  private normalize(target: string): string {
-    return target.replace(/\\/g, '/');
-  }
-}
diff --git a/tests/helpers/mocked-filesystem.ts b/tests/helpers/mocked-filesystem.ts
new file mode 100644
index 0000000..5846f8e
--- /dev/null
+++ b/tests/helpers/mocked-filesystem.ts
@@ -0,0 +1,162 @@
+import path from 'node:path';
+import { FileSystem } from '../../src/core/types';
+
+export class MockedFileSystem implements FileSystem {
+  private directories = new Set<string>();
+  private files = new Map<string, string>();
+  private tempCounter = 0;
+
+  constructor() {
+    this.directories.add('/');
+  }
+
+  addDirectory(dir: string): void {
+    const normalized = this.normalize(dir);
+    this.directories.add(normalized);
+  }
+
+  addFile(target: string, content: string): void {
+    const normalized = this.normalize(target);
+    this.directories.add(path.dirname(normalized));
+    this.files.set(normalized, content);
+  }
+
+  pathExists = jest.fn(async (target: string): Promise<boolean> => {
+    const normalized = this.normalize(target);
+    return this.directories.has(normalized) || this.files.has(normalized);
+  });
+
+  ensureDir = jest.fn(async (target: string): Promise<void> => {
+    this.directories.add(this.normalize(target));
+  });
+
+  mkdtemp = jest.fn(async (prefix: string): Promise<string> => {
+    this.tempCounter += 1;
+    const tempDir = this.normalize(`${prefix}tmp-${this.tempCounter}`);
+    this.directories.add(tempDir);
+    return tempDir;
+  });
+
+  readJson = jest.fn(async (target: string): Promise<unknown> => {
+    const content = await this.readFile(target);
+    return JSON.parse(content);
+  }) as jest.MockedFunction<FileSystem['readJson']>;
+
+  writeJson = jest.fn(async (target: string, data: unknown): Promise<void> => {
+    const normalized = this.normalize(target);
+    this.directories.add(path.dirname(normalized));
+    this.files.set(normalized, `${JSON.stringify(data, null, 2)}\n`);
+  });
+
+  readFile = jest.fn(async (target: string): Promise<string> => {
+    const normalized = this.normalize(target);
+    const content = this.files.get(normalized);
+    if (content === undefined) {
+      throw new Error(`File not found: ${target}`);
+    }
+    return content;
+  });
+
+  isDirectory = jest.fn(async (target: string): Promise<boolean> => {
+    return this.directories.has(this.normalize(target));
+  });
+
+  remove = jest.fn(async (target: string): Promise<void> => {
+    const normalized = this.normalize(target);
+    this.files.delete(normalized);
+    this.directories.delete(normalized);
+
+    for (const filePath of Array.from(this.files.keys())) {
+      if (filePath.startsWith(`${normalized}/`)) {
+        this.files.delete(filePath);
+      }
+    }
+
+    for (const dirPath of Array.from(this.directories)) {
+      if (dirPath.startsWith(`${normalized}/`)) {
+        this.directories.delete(dirPath);
+      }
+    }
+  });
+
+  copy = jest.fn(async (src: string, dest: string): Promise<void> => {
+    const srcNormalized = this.normalize(src);
+    const destNormalized = this.normalize(dest);
+
+    if (this.files.has(srcNormalized)) {
+      const content = this.files.get(srcNormalized);
+      if (content !== undefined) {
+        this.directories.add(path.dirname(destNormalized));
+        this.files.set(destNormalized, content);
+      }
+      return;
+    }
+
+    if (this.directories.has(srcNormalized)) {
+      this.directories.add(destNormalized);
+      for (const dirPath of Array.from(this.directories)) {
+        if (dirPath.startsWith(`${srcNormalized}/`)) {
+          const relative = dirPath.slice(srcNormalized.length);
+          this.directories.add(`${destNormalized}${relative}`);
+        }
+      }
+      for (const [filePath, content] of Array.from(this.files.entries())) {
+        if (filePath.startsWith(`${srcNormalized}/`)) {
+          const relative = filePath.slice(srcNormalized.length);
+          const copiedFilePath = `${destNormalized}${relative}`;
+          this.directories.add(path.dirname(copiedFilePath));
+          this.files.set(copiedFilePath, content);
+        }
+      }
+      return;
+    }
+
+    throw new Error(`Path not found: ${src}`);
+  });
+
+  symlink = jest.fn(async (_target: string, dest: string): Promise<void> => {
+    const normalizedDest = this.normalize(dest);
+    this.directories.add(path.dirname(normalizedDest));
+    this.files.set(normalizedDest, '');
+  });
+
+  readDir = jest.fn(async (target: string): Promise<string[]> => {
+    const normalized = this.normalize(target);
+    const entries = new Set<string>();
+    const prefix = normalized.endsWith('/') ? normalized : `${normalized}/`;
+
+    for (const dir of this.directories) {
+      if (dir === normalized || !dir.startsWith(prefix)) {
+        continue;
+      }
+      const relative = dir.slice(prefix.length);
+      if (relative.length > 0) {
+        entries.add(relative.split('/')[0]);
+      }
+    }
+
+    for (const filePath of this.files.keys()) {
+      if (!filePath.startsWith(prefix)) {
+        continue;
+      }
+      const relative = filePath.slice(prefix.length);
+      if (relative.length > 0) {
+        entries.add(relative.split('/')[0]);
+      }
+    }
+
+    if (!this.directories.has(normalized) && entries.size === 0) {
+      throw new Error(`Directory not found: ${target}`);
+    }
+
+    return Array.from(entries);
+  });
+
+  private normalize(target: string): string {
+    return target.replace(/\\/g, '/');
+  }
+}
+
+export function createMockedFileSystem(): MockedFileSystem {
+  return new MockedFileSystem();
+}
diff --git a/tests/install.test.ts b/tests/install.test.ts
index 3d6a054..1ca9224 100644
--- a/tests/install.test.ts
+++ b/tests/install.test.ts
@@ -2,20 +2,7 @@ import path from 'node:path';
 import { SkillInstaller } from '../src/core/install';
 import { FileSystem, GitClient, LockedSkill } from '../src/core/types';
 import { SkillInstallError } from '../src/core/errors';
-
-const createFsMock = (): jest.Mocked<FileSystem> => ({
-  pathExists: jest.fn(),
-  ensureDir: jest.fn(),
-  mkdtemp: jest.fn(),
-  readJson: jest.fn(),
-  writeJson: jest.fn(),
-  readFile: jest.fn(),
-  isDirectory: jest.fn(),
-  remove: jest.fn(),
-  copy: jest.fn(),
-  symlink: jest.fn(),
-  readDir: jest.fn(),
-});
+import { createMockedFileSystem } from './helpers/mocked-filesystem';
 
 const createGitMock = (): jest.Mocked<GitClient> => ({
   ensureRepo: jest.fn(),
@@ -37,7 +24,7 @@ describe('SkillInstaller', () => {
   let installer: SkillInstaller;
 
   beforeEach(() => {
-    fsMock = createFsMock();
+    fsMock = createMockedFileSystem();
     gitMock = createGitMock();
     installer = new SkillInstaller(fsMock, gitMock);
     gitMock.ensureRepo.mockResolvedValue('/cache/skills/alpha');

From c5feddbc483bda8891b69c9d83291275ab7ad703 Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Mon, 6 Apr 2026 00:03:23 +0200
Subject: [PATCH 08/11] test: add coverage for git fetch, exportPath, and path
 validation

- Add test for fetching existing repositories instead of cloning
- Add test for rejecting absolute subPath values before worktree allocation
- Add test for successful path export with worktree cleanup
- Add test for wrapping missing source path errors while ensuring worktree cleanup
---
 tests/adapters.git.test.ts | 71 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/tests/adapters.git.test.ts b/tests/adapters.git.test.ts
index e2bb7c6..cc9d178 100644
--- a/tests/adapters.git.test.ts
+++ b/tests/adapters.git.test.ts
@@ -39,6 +39,18 @@ describe('ExecaGitClient security hardening', () => {
     );
   });
 
+  it('fetches existing repositories instead of cloning', async () => {
+    const client = new ExecaGitClient('/tmp/cache', mockedFs);
+
+    await client.ensureRepo('https://github.com/acme/skills');
+
+    expect(mockedExeca).toHaveBeenCalledWith(
+      'git',
+      ['-C', '/tmp/cache/https_github.com_acme_skills', 'fetch', '--tags', '--prune', '--force'],
+      expect.any(Object),
+    );
+  });
+
   it('rejects destination values that look like git options', async () => {
     const client = new ExecaGitClient('/tmp/cache', mockedFs);
 
@@ -75,4 +87,63 @@ describe('ExecaGitClient security hardening', () => {
     expect(mockedFs.mkdtemp).not.toHaveBeenCalled();
     expect(mockedExeca).not.toHaveBeenCalled();
   });
+
+  it('rejects absolute subPath values before worktree allocation', async () => {
+    const client = new ExecaGitClient('/tmp/cache', mockedFs);
+    const commit = 'abcdef1234567890abcdef1234567890abcdef12';
+
+    await expect(client.exportPath('/tmp/cache/repo', commit, '/tmp/out', '/etc/passwd')).rejects.toThrow(
+      'Invalid skill path /etc/passwd',
+    );
+
+    expect(mockedFs.mkdtemp).not.toHaveBeenCalled();
+    expect(mockedExeca).not.toHaveBeenCalled();
+  });
+
+  it('exports path successfully and cleans up worktree', async () => {
+    const client = new ExecaGitClient('/tmp/cache', mockedFs);
+    const commit = 'abcdef1234567890abcdef1234567890abcdef12';
+
+    await client.exportPath('/tmp/cache/repo', commit, '/tmp/out', 'skills/jest');
+
+    expect(mockedExeca).toHaveBeenNthCalledWith(
+      1,
+      'git',
+      ['-C', '/tmp/cache/repo', 'worktree', 'add', '--force', '--detach', '/tmp/skilleton-wt-123', commit],
+      expect.any(Object),
+    );
+    expect(mockedFs.remove).toHaveBeenNthCalledWith(1, '/tmp/out');
+    expect(mockedFs.copy).toHaveBeenCalledWith('/tmp/skilleton-wt-123/skills/jest', '/tmp/out');
+    expect(mockedExeca).toHaveBeenNthCalledWith(
+      2,
+      'git',
+      ['-C', '/tmp/cache/repo', 'worktree', 'remove', '--force', '/tmp/skilleton-wt-123'],
+      expect.any(Object),
+    );
+    expect(mockedFs.remove).toHaveBeenNthCalledWith(2, '/tmp/skilleton-wt-123');
+  });
+
+  it('wraps missing source path errors and still cleans up worktree', async () => {
+    const client = new ExecaGitClient('/tmp/cache', mockedFs);
+    const commit = 'abcdef1234567890abcdef1234567890abcdef12';
+    mockedFs.pathExists.mockResolvedValueOnce(false);
+
+    await expect(client.exportPath('/tmp/cache/repo', commit, '/tmp/out', 'skills/missing')).rejects.toThrow(
+      'Failed to export skills/missing from /tmp/cache/repo@abcdef1234567890abcdef1234567890abcdef12: Skill path skills/missing not found in repository /tmp/cache/repo',
+    );
+
+    expect(mockedExeca).toHaveBeenNthCalledWith(
+      1,
+      'git',
+      ['-C', '/tmp/cache/repo', 'worktree', 'add', '--force', '--detach', '/tmp/skilleton-wt-123', commit],
+      expect.any(Object),
+    );
+    expect(mockedExeca).toHaveBeenNthCalledWith(
+      2,
+      'git',
+      ['-C', '/tmp/cache/repo', 'worktree', 'remove', '--force', '/tmp/skilleton-wt-123'],
+      expect.any(Object),
+    );
+    expect(mockedFs.remove).toHaveBeenCalledWith('/tmp/skilleton-wt-123');
+  });
 });

From e2f67226a3f706afcc17edd3f6ae5ee50164fa1a Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Mon, 6 Apr 2026 00:16:20 +0200
Subject: [PATCH 09/11] chore: suppress TypeScript 6.0 deprecation warnings
 temporarily

---
 tsconfig.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tsconfig.json b/tsconfig.json
index 921ddc6..5f88875 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -3,6 +3,7 @@
     "target": "ES2022",
     "module": "commonjs",
     "moduleResolution": "node",
+    "ignoreDeprecations": "6.0",
     "strict": true,
     "esModuleInterop": true,
     "allowSyntheticDefaultImports": true,

From 8b55ac5d646c4026f94c0c389052f886cd52823e Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Mon, 6 Apr 2026 00:19:08 +0200
Subject: [PATCH 10/11] refactor: add addDirectoryTree helper to ensure parent
 directories exist in MockedFileSystem

---
 tests/helpers/mocked-filesystem.ts | 40 +++++++++++++++++++++---------
 1 file changed, 28 insertions(+), 12 deletions(-)

diff --git a/tests/helpers/mocked-filesystem.ts b/tests/helpers/mocked-filesystem.ts
index 5846f8e..c1c49bc 100644
--- a/tests/helpers/mocked-filesystem.ts
+++ b/tests/helpers/mocked-filesystem.ts
@@ -11,13 +11,12 @@ export class MockedFileSystem implements FileSystem {
   }
 
   addDirectory(dir: string): void {
-    const normalized = this.normalize(dir);
-    this.directories.add(normalized);
+    this.addDirectoryTree(this.normalize(dir));
   }
 
   addFile(target: string, content: string): void {
     const normalized = this.normalize(target);
-    this.directories.add(path.dirname(normalized));
+    this.addDirectoryTree(path.dirname(normalized));
     this.files.set(normalized, content);
   }
 
@@ -27,13 +26,13 @@ export class MockedFileSystem implements FileSystem {
   });
 
   ensureDir = jest.fn(async (target: string): Promise<void> => {
-    this.directories.add(this.normalize(target));
+    this.addDirectoryTree(this.normalize(target));
   });
 
   mkdtemp = jest.fn(async (prefix: string): Promise<string> => {
     this.tempCounter += 1;
     const tempDir = this.normalize(`${prefix}tmp-${this.tempCounter}`);
-    this.directories.add(tempDir);
+    this.addDirectoryTree(tempDir);
     return tempDir;
   });
 
@@ -44,7 +43,7 @@ export class MockedFileSystem implements FileSystem {
 
   writeJson = jest.fn(async (target: string, data: unknown): Promise<void> => {
     const normalized = this.normalize(target);
-    this.directories.add(path.dirname(normalized));
+    this.addDirectoryTree(path.dirname(normalized));
     this.files.set(normalized, `${JSON.stringify(data, null, 2)}\n`);
   });
 
@@ -86,25 +85,25 @@ export class MockedFileSystem implements FileSystem {
     if (this.files.has(srcNormalized)) {
       const content = this.files.get(srcNormalized);
       if (content !== undefined) {
-        this.directories.add(path.dirname(destNormalized));
+        this.addDirectoryTree(path.dirname(destNormalized));
         this.files.set(destNormalized, content);
       }
       return;
     }
 
     if (this.directories.has(srcNormalized)) {
-      this.directories.add(destNormalized);
+      this.addDirectoryTree(destNormalized);
       for (const dirPath of Array.from(this.directories)) {
         if (dirPath.startsWith(`${srcNormalized}/`)) {
           const relative = dirPath.slice(srcNormalized.length);
-          this.directories.add(`${destNormalized}${relative}`);
+          this.addDirectoryTree(`${destNormalized}${relative}`);
         }
       }
       for (const [filePath, content] of Array.from(this.files.entries())) {
         if (filePath.startsWith(`${srcNormalized}/`)) {
           const relative = filePath.slice(srcNormalized.length);
           const copiedFilePath = `${destNormalized}${relative}`;
-          this.directories.add(path.dirname(copiedFilePath));
+          this.addDirectoryTree(path.dirname(copiedFilePath));
           this.files.set(copiedFilePath, content);
         }
       }
@@ -116,7 +115,8 @@ export class MockedFileSystem implements FileSystem {
 
   symlink = jest.fn(async (_target: string, dest: string): Promise<void> => {
     const normalizedDest = this.normalize(dest);
-    this.directories.add(path.dirname(normalizedDest));
+    this.files.delete(normalizedDest);
+    this.addDirectoryTree(path.dirname(normalizedDest));
     this.files.set(normalizedDest, '');
   });
 
@@ -145,7 +145,7 @@ export class MockedFileSystem implements FileSystem {
       }
     }
 
-    if (!this.directories.has(normalized) && entries.size === 0) {
+    if (!this.directories.has(normalized)) {
       throw new Error(`Directory not found: ${target}`);
     }
 
@@ -155,6 +155,22 @@ export class MockedFileSystem implements FileSystem {
   private normalize(target: string): string {
     return target.replace(/\\/g, '/');
   }
+
+  private addDirectoryTree(dir: string): void {
+    const normalized = this.normalize(dir);
+    if (!normalized || normalized === '/') {
+      this.directories.add('/');
+      return;
+    }
+
+    const segments = normalized.split('/').filter(Boolean);
+    let current = normalized.startsWith('/') ? '/' : '';
+
+    for (const segment of segments) {
+      current = current === '/' ? `/${segment}` : current ? `${current}/${segment}` : segment;
+      this.directories.add(current);
+    }
+  }
 }
 
 export function createMockedFileSystem(): MockedFileSystem {

From a4ea7765c6e59a18415ba5de78217862655aef1f Mon Sep 17 00:00:00 2001
From: Abdeldjalil Fortas <9090674+Fcmam5@users.noreply.github.com>
Date: Mon, 6 Apr 2026 00:40:34 +0200
Subject: [PATCH 11/11] docs: Add Advisory URL

---
 SECURITY.md | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/SECURITY.md b/SECURITY.md
index 7c4bca0..9192b4c 100644
--- a/SECURITY.md
+++ b/SECURITY.md
@@ -4,9 +4,10 @@
 
 | Version | Supported |
 | ------- | --------- |
-| 0.1.x   | ✅        |
+| >=0.3.1 | ✅        |
+| <0.3.1  | ❌ (deprecated) |
 
-Skilleton CLI is currently pre-1.0, but we treat every tagged release as security-supported until a newer patch is published.
+Versions earlier than `0.3.1` are deprecated due to security fixes (see the [Security Advisory](https://github.com/Fcmam5/skilleton/security/advisories/GHSA-5g3j-89fr-r2vp)). Please upgrade to `0.3.1` or later.
 
 ## Reporting a Vulnerability