diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9d13f551..62fb8561 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,25 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 
+## [Unreleased]
+
+### Fixed
+- **Windows PowerShell compatibility**: Fixed SessionStart hook error on Windows systems
+  - Replaced bash-specific command (`[`, `&&`, `||`) with cross-platform Node.js installer
+  - Created `ensure-dependencies.js` script for automatic dependency installation
+  - Dependencies (`better-sqlite3`) now install correctly on Windows, macOS, and Linux
+
+### Added
+- **Cross-platform dependency installer**: New `ensure-dependencies.js` script handles runtime dependency installation
+- **Automatic package.json generation**: Build process now creates `package.json` in `plugin/scripts/` directory
+- **Enhanced build output**: Build script now generates installer alongside hooks and services
+
+### Changed
+- **SessionStart hook command**: Now uses `node ensure-dependencies.js && node context-hook.js` instead of bash syntax
+- **Build process**: Added installer script bundling and package.json generation steps
+- **.gitignore**: Added `plugin/scripts/package-lock.json` to prevent version control conflicts
+
+
 ## [4.2.1] - 2025-10-22
 
 ### Added
diff --git a/CLAUDE.md b/CLAUDE.md
index 66aba352..6f66a641 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -26,6 +26,7 @@ This creates a continuous memory system where Claude can learn from past session
 Claude-mem integrates with Claude Code through 5 lifecycle hooks:
 
 1. **SessionStart Hook** (`context-hook`)
+   - Auto-installs dependencies on first run (cross-platform Node.js installer)
    - Injects context from previous sessions
    - Auto-starts PM2 worker service
    - Retrieves last 10 session summaries with three-tier verbosity (v4.2.0)
@@ -199,12 +200,36 @@ claude-mem/
 npm run build && git commit -a -m "Build and update" && git push && cd ~/.claude/plugins/marketplaces/thedotmack/ && git pull && pm2 flush claude-mem-worker && pm2 restart claude-mem-worker && pm2 logs claude-mem-worker --nostream
 ```
 
-1) Compiles TypeScript and outputs hook executables to `plugin/scripts/`
-2) Does all the things needed to update and test since plugin-based installs are out of the .claude/ folder
+1. Compiles TypeScript and outputs hook executables to `plugin/scripts/`
+2. Generates `ensure-dependencies.js` - cross-platform installer script
+3. Creates `package.json` in `plugin/scripts/` with runtime dependencies
+4. Does all the things needed to update and test since plugin-based installs are out of the .claude/ folder
+
+**Build Outputs**:
+- Hook executables: `*-hook.js` (ESM format)
+- Worker service: `worker-service.cjs` (CJS format)
+- Search server: `search-server.js` (ESM format)
+- Dependency installer: `ensure-dependencies.js` (ESM format)
+- Runtime manifest: `package.json` (includes `better-sqlite3` dependency)
 
 ## Version History
 
-### v4.2.0 (Current)
+### v4.2.2 (Upcoming)
+**Breaking Changes**: None (patch version)
+
+**Fixes**:
+- Fixed Windows PowerShell compatibility issue with SessionStart hook
+- Replaced bash-specific installation command with cross-platform Node.js installer
+- Added `ensure-dependencies.js` script for automatic dependency installation
+- Build process now generates `package.json` with runtime dependencies in `plugin/scripts/`
+
+**Technical Details**:
+- Created `src/bin/ensure-dependencies.ts` for cross-platform dependency management
+- Updated `plugin/hooks/hooks.json` to use Node.js command chain instead of shell syntax
+- Dependencies (`better-sqlite3`) are now installed automatically on first run across all platforms
+- Added `.gitignore` rule for `plugin/scripts/package-lock.json`
+
+### v4.2.0
 **Breaking Changes**: None (minor version)
 
 **Features**:
diff --git a/README.md b/README.md
index 950dcffd..d48b8277 100644
--- a/README.md
+++ b/README.md
@@ -253,14 +253,18 @@ npm install -g claude-mem
 
 ### Post-Installation
 
-1. **Verify Plugin Installation**
+1. **Automatic Dependency Installation**
+
+   The plugin automatically installs required dependencies (`better-sqlite3`) on first run. This happens when you first start Claude Code after installation. The process is cross-platform and works on Windows, macOS, and Linux.
+
+2. **Verify Plugin Installation**
 
    Check that hooks are configured in Claude Code:
    ```bash
    cat plugin/hooks/hooks.json
    ```
 
-2. **Data Directory Location**
+3. **Data Directory Location**
 
    v4.0.0+ stores data in `${CLAUDE_PLUGIN_ROOT}/data/`:
    - Database: `${CLAUDE_PLUGIN_ROOT}/data/claude-mem.db`
@@ -272,13 +276,13 @@ npm install -g claude-mem
    export CLAUDE_MEM_DATA_DIR=/custom/path
    ```
 
-3. **Check Worker Logs**
+4. **Check Worker Logs**
 
    ```bash
    npm run worker:logs
    ```
 
-4. **Test Context Retrieval**
+5. **Test Context Retrieval**
 
    ```bash
    npm run test:context