docs: add Windows contributor setup guide

CONTRIBUTING.md

@@ -19,6 +19,10 @@ pnpm install
 pnpm build
 ```
 
+If you're developing on Windows, read [docs/WINDOWS_SETUP.md](docs/WINDOWS_SETUP.md)
+before running the commands above. It covers shell differences, pnpm setup,
+line endings, and a few Windows-specific gotchas that commonly block first-time contributors.
+
 ## Project Structure
 
 ```
@@ -45,6 +49,7 @@ git checkout -b feature/your-feature-name
 ```
 
 Branch naming:
+
 - `feature/pdf-export` — new features
 - `fix/scoring-bug` — bug fixes
 - `archetype/mobile-engineer` — new role archetypes
@@ -94,6 +99,7 @@ git push origin feature/your-feature-name
 ```
 
 Then open a PR on GitHub. Fill in the template — it asks:
+
 - What does this PR do?
 - Related issue number
 - Type of change
@@ -166,6 +172,7 @@ ARCHETYPES.set("mobile-engineer", {
 ## First Time Contributing to Open Source?
 
 Welcome! You belong here. These resources help:
+
 - [How to Contribute to Open Source](https://opensource.guide/how-to-contribute/)
 - [First Timers Only](https://www.firsttimersonly.com/)
 - [GitHub Flow](https://docs.github.com/en/get-started/quickstart/github-flow)

docs/WINDOWS_SETUP.md

@@ -0,0 +1,114 @@
+# Windows Setup Guide
+
+This guide fills in the Windows-specific details that are easy to miss when
+you follow the standard setup steps in [../CONTRIBUTING.md](../CONTRIBUTING.md).
+
+## 1. Install Node.js
+
+This project supports Node.js 20 and newer. The commands below install Node.js
+20 to match the minimum supported version:
+
+- `nvm-windows`: install it from the [nvm-windows releases](https://github.com/coreybutler/nvm-windows/releases), then run `nvm install 20` and `nvm use 20`
+- Direct download: install the latest archived Node.js 20 build from [nodejs.org](https://nodejs.org/dist/latest-v20.x/)
+
+Confirm the version after installation:
+
+```powershell
+node --version
+```
+
+## 2. Install pnpm
+
+We use `pnpm` for workspace installs and Turbo tasks.
+
+Recommended:
+
+```powershell
+corepack enable
+pnpm --version
+```
+
+Fallback if `corepack` is unavailable:
+
+```powershell
+npm install -g pnpm
+pnpm --version
+```
+
+## 3. Configure Git line endings
+
+Set Git to normalize line endings for Windows checkouts:
+
+```powershell
+git config --global core.autocrlf true
+```
+
+That prevents accidental line-ending noise in generated diffs.
+
+## 4. Choose your shell
+
+Both PowerShell and Git Bash work. Pick one and stay consistent for a session.
+
+### PowerShell
+
+Use this when you want the most native Windows experience:
+
+```powershell
+git clone https://github.com/YOUR-USERNAME/cv-builder.git
+cd cv-builder
+pnpm install
+pnpm build
+pnpm test
+```
+
+### Git Bash
+
+Use this if you prefer Unix-style shell behavior and command syntax:
+
+```bash
+git clone https://github.com/YOUR-USERNAME/cv-builder.git
+cd cv-builder
+pnpm install
+pnpm build
+pnpm test
+```
+
+## 5. Common gotchas
+
+### Path length limits
+
+If you see checkout or install failures about long paths, enable Windows long
+path support in Git:
+
+```powershell
+git config --global core.longpaths true
+```
+
+### PowerShell execution policy
+
+If PowerShell blocks locally installed scripts, open a new PowerShell window as
+your user and run:
+
+```powershell
+Set-ExecutionPolicy -Scope CurrentUser RemoteSigned
+```
+
+If your machine is company-managed and this policy is locked down, use Git Bash
+instead of changing the policy.
+
+### Reopen the shell after installs
+
+After installing Node.js, pnpm, or Git, close and reopen your terminal before
+retrying `pnpm install` so the updated PATH is available.
+
+## 6. Contributor workflow reminder
+
+Once the environment is ready, return to the standard project workflow in
+[../CONTRIBUTING.md](../CONTRIBUTING.md):
+
+```powershell
+pnpm install
+pnpm build
+pnpm test
+pnpm format:check
+```