Prerequisites

What we’re building

Before writing a line of DevBlog, you need a working local toolchain: a Node runtime, a package manager, Docker to run the stack, the Nest CLI to scaffold the API, a MongoDB shell to inspect data, and a GraphQL client to poke the API. This lesson installs each on macOS and gives you a command to confirm it works, with the output you should expect.

Why

Every tool here earns its place:

Node 20+ runs both the NestJS API and the Next.js front end.
npm or pnpm installs and manages dependencies for each package.
Docker Desktop runs MongoDB, the API, and the web app together with one command — no local Mongo install required.
The Nest CLI scaffolds modules, resolvers, and services so the backend stays consistent.
mongosh lets you open the database and read the documents your API writes, which is invaluable when debugging.
A GraphQL client lets you run queries and mutations by hand before any UI exists.

Set it up

Work through each tool and run its verify command. Versions will differ slightly; the shape of the output is what matters.

Node 20+ — the runtime for both apps. Install via nvm (recommended) or the macOS installer, then:

node -v
# v20.11.1

Any v20.x or newer is fine. If you see v18 or lower, upgrade before continuing.

npm / pnpm — the package manager. npm ships with Node; pnpm is faster and disk-efficient for a monorepo:

npm -v
# 10.2.4

# optional but recommended
npm i -g pnpm
pnpm -v
# 8.15.1

Docker Desktop — runs the whole stack. Install Docker Desktop for Mac, launch it once so the engine starts, then verify both the CLI and the Compose plugin:

docker --version
# Docker version 24.0.6, build ed223bc

docker compose version
# Docker Compose version v2.23.0

Note it is docker compose (a subcommand), not the old docker-compose binary. If docker --version errors, make sure Docker Desktop is actually running.

The Nest CLI — scaffolds the backend. Install it globally:

npm i -g @nestjs/cli
nest --version
# 10.3.0

mongosh — the MongoDB shell for inspecting data. You have two options. If you install Homebrew’s mongosh:

brew install mongosh
mongosh --version
# 2.1.1

Or, once the stack is running, use the copy already inside the Mongo container — no local install needed:

docker compose exec mongo mongosh
# Current Mongosh Log ID: ...
# test>

A GraphQL client — for testing the API by hand. NestJS + Apollo serves a built-in playground at http://localhost:3000/graphql; opening that URL in a browser once the API is up gives you a query editor with schema-aware autocomplete:

Open http://localhost:3000/graphql
# Apollo Sandbox / GraphQL playground loads with your schema in the Docs tab

You can also use the standalone Apollo Sandbox and point it at the same URL. Either works.

Verify

Run this checklist top to bottom; every command should print a version, not an error:

node -v            # v20+
npm -v             # 10+
docker --version   # Docker version 24+
docker compose version   # v2+
nest --version     # 10+
mongosh --version  # 2+  (or use docker compose exec mongo mongosh)

Then open http://localhost:3000/graphql once the API exists (it does not yet — that comes in a later module) to confirm the GraphQL client loads. If every line above prints a version, your machine is ready.

Recap

DevBlog needs Node 20+, a package manager (npm or pnpm), Docker Desktop with the Compose plugin, the Nest CLI, mongosh (local or via the container), and a GraphQL client (the built-in /graphql playground or Apollo Sandbox). Each has a one-line verify command; when they all print versions, you can move on.

Next: Roadmap →