Build Your First App in 10 Minutes With Claude CLI — Complete Beginner Walkthrough

If you've ever stared at a blank IDE wondering where to start, this article is for you. We're going to skip the tutorial spiral — "first install Node, then learn npm, then learn Express, then…" — and just build something that runs. A real, working REST API with full CRUD endpoints, error handling, and an in-memory store. Total time: under ten minutes. Total lines of code you write yourself: zero.

The video above is the live demo. This article is the cheat sheet you can keep open while you follow along. Bring a terminal, an Anthropic account, and ten minutes — that's the whole list.

Before you start: the 3 prerequisites

If Claude CLI is already installed on your machine, skip this section. If not, here's the minimum bar — and it really is the minimum:

1. Node.js 18 or higher — install from nodejs.org/en/download. Verify with `node --version`.
2. Git — install from git-scm.com. The default options are fine; this also gives you Git Bash on Windows.
3. An Anthropic account — either a Claude.ai Pro/Max subscription, or an API key from console.anthropic.com with a few dollars of credits.

Then install Claude CLI globally and authenticate. Two commands:

npm install -g @anthropic-ai/claude-code
claude auth login

Your browser opens, you authorize the CLI, the terminal confirms. You're in. (Full setup walkthrough is in my Claude CLI Setup Guide — link at the end.)

Step 1: make a folder, open Claude

Three commands. This is the entire "setup" for your new project.

mkdir todo-project
cd todo-project
claude

You're now inside Claude CLI, in an empty folder. The agent is waiting for direction. Notice what just didn't happen: no `npm init`, no choosing a framework, no scaffolding template. The folder is empty on purpose — Claude is going to fill it.

Step 2: paste the prompt

Create a simple todo list API using Express.js. It should have endpoints to create, read, update, and delete todos. Each todo should have an id, title, description, and completed status. Include proper error handling and use in-memory storage.

Hit enter. Now watch what happens — and resist the urge to interrupt. Claude doesn't just dump code. It thinks, plans, and then writes.

Step 3: what Claude actually does

Inside the next minute or two, the CLI walks through five concrete steps — out loud — so you can follow along:

1. Creates `package.json` with the right dependencies.
2. Sets up the Express server with a clean entry point.
3. Writes the routes for create, read, update, and delete.
4. Adds error-handling middleware so bad requests return clean 4xx responses.
5. Generates a README documenting every endpoint, the request/response shape, and how to run it.

By the time it's done, you have a complete project. Open the files. Read the code. This is the moment most beginners skip — and it's the moment that turns a tutorial into actual learning. You'll see Express conventions, middleware composition, error patterns. You'll see the why, not just the what.

Step 4: run it

Two commands. The first installs the dependencies Claude added to `package.json`. The second runs the server.

npm install
node server.js

You'll see the server log on a port (usually 3000). Open another terminal — or Postman, or curl, or your browser's dev tools — and hit your endpoints. POST a todo. GET the list. PUT an update. DELETE one. Every endpoint Claude generated, working, on your machine, in under ten minutes.

What to do next (and what NOT to do)

Two failure modes show up after the first "it works." Avoid both.

• Don't immediately throw a giant prompt at it. "Now add authentication, a database, a frontend, and deploy it." Big-bang prompts produce big-bang bugs. Add one thing, run it, commit, repeat.
• Don't skip reading the code. The point of Claude CLI isn't to avoid learning — it's to learn faster, on real code that actually runs. Read the routes. Read the middleware. Ask Claude to explain anything that's unclear.

Instead, take small confident steps. Try these as your next prompts inside the same session: "Persist the todos to a JSON file so they survive restarts," then "Add input validation so empty titles return a 400," then "Write Jest tests for every endpoint." Each one is two minutes of generation and ten minutes of reading. That's the loop that makes you faster every week.

From here, two paths

If you want to go wider — building a Next.js app with auth, database, and a real UI — watch the Complex Task tutorial in this same playlist; the prompt pattern is the same, the scope is bigger. If you want to go deeper into Claude CLI itself — power tips, --review mode, working in existing repos — the Power Tips chapter in the Claude Code book on this site has the full reference.