diff --git a/CLAUDE.md b/CLAUDE.md
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@@ -0,0 +1,48 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+PinMe is a zero-config CLI tool for deploying static sites to IPFS. Built with TypeScript, bundled with esbuild, published to npm as `pinme`. Users run commands like `pinme upload dist` to deploy frontends.
+
+## Build & Dev
+
+```bash
+npm run build          # Production build (esbuild → dist/index.js)
+npm run dev            # Dev build (NODE_ENV=development)
+node test/build-env.test.js  # Run tests (node:test, no framework)
+```
+
+Build uses `build.js` (esbuild), NOT `rollup.config.js` (legacy, unused). esbuild reads `.env` via dotenv at build time and injects env vars as `process.env.*` defines.
+
+The output is a single CJS file at `dist/index.js` with a shebang, used as the `pinme` CLI binary.
+
+## Architecture
+
+- `bin/index.ts` — CLI entry point, uses `commander` to register all commands
+- `bin/*.ts` — Individual command implementations (upload, save, create, bind, importCar, exportCar, delete, etc.)
+- `bin/utils/` — Shared utilities:
+  - `config.ts` — `APP_CONFIG` singleton, all API base URLs and tuning knobs from env vars
+  - `apiClient.ts` — Axios client factory (`createPinmeApiClient`, `createCarApiClient`)
+  - `pinmeApi.ts` — High-level API wrappers (domain binding, wallet, CAR export, etc.)
+  - `uploadToIpfs.ts` / `uploadToIpfsSplit.ts` — IPFS upload logic (single file vs chunked)
+  - `webLogin.ts` — Auth token management (reads from `~/.pinme/`)
+  - `domainValidator.ts` — Domain name validation and DNS vs subdomain detection
+  - `cliError.ts` — Structured CLI error types
+- `bin/services/uploadService.ts` — Upload orchestration (hash encryption, URL generation)
+- `skills/` — Claude Code skill definitions for this project
+
+## Key Patterns
+
+- Auth: AppKey stored locally at `~/.pinme/`. Auth headers injected via `getAuthHeaders()` in `webLogin.ts`.
+- API clients: Always use `createPinmeApiClient()` or `createCarApiClient()` from `apiClient.ts`, never raw axios.
+- Token expiry: `pinmeApi.ts` has centralized token-expired detection (`isTokenExpired`) — all API calls should go through wrappers there.
+- Config: All env-driven config lives in `APP_CONFIG` (`config.ts`). Don't read `process.env` directly elsewhere.
+- The `save` command reads `pinme.toml` from project root for full-stack deploy (frontend + Cloudflare Worker + D1).
+
+## Code Style
+
+- Prettier: single quotes, trailing commas, 80 char width
+- TypeScript with `strict: false`, target ESNext, module ESNext
+- CLI output uses `chalk` for colors, `ora` for spinners, `inquirer` for prompts, `figlet` for banner
diff --git a/skills/pinme-email/SKILL.md b/skills/pinme-email/SKILL.md
index af2aa2b..fb21a04 100644
--- a/skills/pinme-email/SKILL.md
+++ b/skills/pinme-email/SKILL.md
@@ -28,7 +28,7 @@ export interface Env {
 
 **Endpoint:** `POST {BASE_URL}/api/v4/send_email`
 **Authentication:** `X-API-Key` header (using `env.API_KEY`)
-**Sender:** Automatically set to `{project_name}@pinme.dev`
+**Sender:** Automatically set to `{project_name}@pinme.cloud`
 
 ### Request Format