Set up your dev environment — in the order that actually works.

macOS

1. Run the install command below, then click Install in the dialog that appears.
2. Wait. This is several hundred megabytes and takes 5 to 10 minutes on a good connection.

xcode-select --install

Done when: xcode-select -p prints a path ending in CommandLineTools or Xcode.app.

macOS

1. Open brew.sh and copy the install command from the top of the page. Copy it from there rather than from here: it is long, and a version of it that got broken across two lines will fail in a way that is hard to read.
2. Paste it into your terminal and press Enter. It asks for your password, and the password does not echo as you type. That is the terminal working correctly, not a dead keyboard.
3. Read the "Next steps" block it prints at the end and run the two or three commands it lists. See the warning below.
4. Open a new terminal.

Done when: brew --version prints a version number.

Linux

1. Open brew.sh and copy the install command from the top of the page.
2. Paste it into your terminal and press Enter.
3. Run the commands from the "Next steps" block it prints at the end.
4. Open a new terminal.

Done when: brew --version prints a version number.

macOS

1. Download from code.visualstudio.com, unzip, and drag Visual Studio Code.app into Applications.
2. Open VS Code and press Cmd+Shift+P to open the command palette.
3. Type shell command and choose Shell Command: Install 'code' command in PATH. Without this step the code command does not exist in your terminal.
4. Open a new terminal.

Done when: code --version prints a version number, three lines.

Windows

1. Download from code.visualstudio.com. The default button gives you the User Installer, which needs no administrator rights.
2. Run it. On the Select Additional Tasks screen, confirm Add to PATH is checked. It usually is, but not always.
3. Open a new terminal after it finishes.

Done when: code --version prints a version number, three lines.

Linux

1. Download the .deb from code.visualstudio.com and install it, or add Microsoft's apt repository if you want it to update with the rest of your system.
2. Open a new terminal.

Done when: code --version prints a version number, three lines.

macOS

1. Git ships inside the Command Line Tools, so it is probably already there. Run git --version. If a dialog appears offering to install, accept it.
2. Set your name and email with the two commands below. Use the same email as your GitHub account.
3. Point Git at VS Code and default new repositories to main, which is what the Windows installer does for you and macOS does not.

git config --global user.name "Your Full Name"git config --global user.email "you@example.com"git config --global core.editor "code --wait"git config --global init.defaultBranch main

Done when: git --version prints a version number.

Windows

1. Download the installer from git-scm.com and run it. It has roughly 14 screens. Four of them need a change; the rest are correct as they come.
2. Choosing the default editor: change this from Vim to Use Visual Studio Code as Git's default editor. This is the most important screen in the installer.
3. Adjusting the name of the initial branch: choose Override the default branch name and leave it as main, which is what GitHub expects.
4. Adjusting your PATH environment: keep the recommended middle option.
5. Choosing a credential helper: keep Git Credential Manager. It opens a browser to log into GitHub rather than asking for a password you do not have.
6. Open a new terminal, then set your name and email with the two commands below.

git config --global user.name "Your Full Name"git config --global user.email "you@example.com"git config --global core.longpaths true

Done when: git --version prints a version number.

Linux

1. Install it from your package manager with the command below.
2. Set your name and email with the two commands below. Use the same email as your GitHub account.
3. Point Git at VS Code and default new repositories to main.

sudo apt update && sudo apt install gitgit config --global user.name "Your Full Name"git config --global user.email "you@example.com"git config --global core.editor "code --wait"git config --global init.defaultBranch main

Done when: git --version prints a version number.

macOS

1. Open docs.astral.sh/uv and copy the install command, or run brew install uv.
2. Open a new terminal.
3. Install an interpreter and start a project with the commands below.
4. Point VS Code at the project's environment: open the project folder, press Cmd+Shift+P, run Python: Select Interpreter, and choose the one inside .venv.

uv python installuv init my-projectcd my-projectuv venv

Done when: uv --version prints a version number.

uv run python -c "import sys; print(sys.executable)"

Prints the interpreter uv actually uses. That path is the one your editor needs to be pointed at, so it is worth reading rather than skipping.

Windows

1. Open docs.astral.sh/uv and copy the install command, or run winget install astral-sh.uv.
2. Open a new terminal.
3. Install an interpreter and start a project with the commands below.
4. Point VS Code at the project's environment: open the project folder, press Ctrl+Shift+P, run Python: Select Interpreter, and choose the one inside .venv.

uv python installuv init my-projectcd my-projectuv venv

Done when: uv --version prints a version number.

uv run python -c "import sys; print(sys.executable)"

Prints the interpreter uv actually uses. That path is the one your editor needs to be pointed at, so it is worth reading rather than skipping.

Linux

1. Open docs.astral.sh/uv and copy the install command.
2. Open a new terminal.
3. Install an interpreter and start a project with the commands below.
4. Point VS Code at the project's environment: open the project folder, press Ctrl+Shift+P, run Python: Select Interpreter, and choose the one inside .venv.

uv python installuv init my-projectcd my-projectuv venv

Done when: uv --version prints a version number.

uv run python -c "import sys; print(sys.executable)"

Prints the interpreter uv actually uses. That path is the one your editor needs to be pointed at, so it is worth reading rather than skipping.

macOS

1. Download the .pkg from python.org/downloads and run it.
2. Open the installed folder in Applications and double-click Install Certificates.command. Skipping this produces an SSL error weeks later that is genuinely hard to trace back to here.
3. Open a new terminal.

Done when: python3 --version prints a version number starting with 3.

Windows

1. Download from python.org/downloads using the large button at the top.
2. On the first installer screen, check Add python.exe to PATH before clicking anything else. It sits at the bottom of that screen and is unchecked by default. See the warning below.
3. Finish the install and open a new terminal.

Done when: py --version prints a version number starting with 3.

Linux

1. Python is almost certainly already installed. Check with python3 --version before installing anything.
2. If the version is too old for what you need, add the deadsnakes PPA or use uv rather than replacing the system Python, which other parts of your OS depend on.

Done when: python3 --version prints a version number starting with 3.

macOS

1. Open github.com/nvm-sh/nvm and copy the install command from the README. Copy it from there rather than from here: the command has nvm's own version number in the URL, so a copy that sits in a guide installs an old nvm.
2. Run it, then open a new terminal. The installer appends a block to your shell profile, and profiles are only read when a shell starts.
3. Install Node and set it as your default with the commands below.

nvm install --ltsnvm use --ltsnvm alias default lts/*

Done when: nvm --version prints a version number.

node --version

Proves nvm actually put a Node on your PATH, which nvm --version alone does not tell you.

Windows

1. Uninstall any existing Node.js first, through Settings → Apps. See the warning below. This is not optional.
2. Download nvm-setup.exe from github.com/coreybutler/nvm-windows/releases and run it.
3. Close every terminal and open a new one, this time as administrator: right-click your terminal in the Start menu and choose Run as administrator.
4. Install Node and select it with the commands below. Note the syntax has no double dashes, which is where most Windows nvm instructions on the internet go wrong.

nvm install ltsnvm use lts

Done when: nvm --version prints a version number.

node --version

Proves nvm actually put a Node on your PATH, which nvm --version alone does not tell you.

Linux

1. Open github.com/nvm-sh/nvm and copy the install command from the README.
2. Run it, then open a new terminal.
3. Install Node and set it as your default with the commands below.

nvm install --ltsnvm use --ltsnvm alias default lts/*

Done when: nvm --version prints a version number.

node --version

Proves nvm actually put a Node on your PATH, which nvm --version alone does not tell you.

macOS

1. From nodejs.org, take the LTS download, not Current. LTS is currently the Node 24 line.
2. Run the .pkg and accept the defaults.
3. Open a new terminal.

Done when: node --version prints a version number.

npm --version

npm comes with Node, so a Node that works and an npm that does not means the PATH is half set up.

Windows

1. From nodejs.org, take the LTS download, not Current.
2. Run the .msi. Leave Tools for Native Modules unchecked. Checking it opens a PowerShell window that downloads Chocolatey, Python, and Visual Studio Build Tools: twenty minutes or more, frequently fails, and rarely needed.
3. Open a new PowerShell terminal and allow npm to run, using the command below. Windows blocks it by default.

Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy RemoteSignedGet-ExecutionPolicy -Scope CurrentUser

Done when: node --version prints a version number.

npm --version

npm comes with Node, so a Node that works and an npm that does not means the PATH is half set up.

Linux

1. Use the NodeSource repository or a version manager. The version in your distribution's own repository is usually several years old.

Done when: node --version prints a version number.

npm --version

npm comes with Node, so a Node that works and an npm that does not means the PATH is half set up.

macOS

1. Download the installer from go.dev/dl and run it.
2. Open a new terminal.

Done when: go version prints a version number.

Windows

1. Download the .msi from go.dev/dl and run it.
2. Open a new terminal.

Done when: go version prints a version number.

Linux

1. Install the distribution package, or download the tarball from go.dev/dl and follow the instructions on that page.
2. Open a new terminal.

Done when: go version prints a version number.

macOS

1. Open rustup.rs and copy the install command.
2. Run it and accept the default installation option.
3. Open a new terminal.

Done when: rustc --version prints a version number.

cargo --version

cargo is the build tool and package manager, and it is what you will actually type day to day.

Windows

1. Open rustup.rs and download rustup-init.exe.
2. Run it. It checks for the MSVC build tools and offers to install them if they are missing. Accept: Rust cannot link a program on Windows without them.
3. Open a new terminal.

Done when: rustc --version prints a version number.

cargo --version

cargo is the build tool and package manager, and it is what you will actually type day to day.

Linux

1. Open rustup.rs and copy the install command.
2. Run it and accept the default installation option.
3. Open a new terminal.

Done when: rustc --version prints a version number.

cargo --version

cargo is the build tool and package manager, and it is what you will actually type day to day.

macOS

1. The compiler comes with the Xcode Command Line Tools, which are already in your list above.
2. What you get is clang++. g++ also works, but on a Mac it is a shim for clang rather than GNU g++, which is worth knowing before you follow GCC-specific documentation.
3. For anything past a single file, add CMake: brew install cmake.

Done when: g++ --version prints a version banner.

Windows

1. From visualstudio.com/downloads, scroll to Tools for Visual Studio and download Build Tools for Visual Studio. You do not need the full IDE.
2. In the installer, select the Desktop development with C++ workload. This is several gigabytes and takes a while.
3. Tick C++ CMake tools for Windows in the same workload while you are there, rather than coming back for it later.
4. When it finishes, open Developer Command Prompt for VS from the Start menu. See the warning below: this is not the same as your normal terminal.

Done when: cl prints a version banner.

Linux

1. Install build-essential with the command below. This is g++, make, and the standard headers together.
2. Add CMake at the same time if you will build anything past a single file.

sudo apt update && sudo apt install build-essential cmake

Done when: g++ --version prints a version banner.

macOS

1. Apple removed PHP from macOS in Monterey, so there is nothing already on your machine to use.
2. Run brew install php. Homebrew builds it with the common extensions already enabled, including PDO SQLite, so there is nothing to configure afterward.
3. Open a new terminal.

Done when: php --version prints a version number.

php --ini

Shows which config file PHP actually loaded. A (none) there means it never found your php.ini, which is why an extension you enabled appears to be ignored. php -m lists what is enabled.

Windows

1. Install the Visual C++ Redistributable from aka.ms/vs/17/release/vc_redist.x64.exe first, or PHP fails to start with a missing VCRUNTIME140.dll.
2. From windows.php.net/download, find the Non Thread Safe box, which is the right one for command-line use, and take the Zip link inside it.
3. Extract it to C:\php. Not Program Files: the space in the path and its permissions both cause trouble. Confirm php.exe sits directly in that folder rather than in a nested one.
4. Copy php.ini-development to php.ini in the same folder.
5. Open php.ini and uncomment the extensions you need by deleting the leading semicolon. Be careful with extension_dir = "ext": there is a similar-looking extension_dir = "./" a few lines above it, and uncommenting that one instead breaks every extension.
6. Add C:\php to your user PATH, not the system PATH.
7. Restart every terminal and your editor. A program only reads the PATH when it starts.

Done when: php --version prints a version number.

php --ini

Shows which config file PHP actually loaded. A (none) there means it never found your php.ini, which is why an extension you enabled appears to be ignored. php -m lists what is enabled.

Linux

1. Install the distribution package with the command below.
2. If you need a current PHP rather than whatever your distribution froze on, add the ondrej PPA instead and install from there.
3. Open a new terminal.

sudo apt update && sudo apt install php-cli

Done when: php --version prints a version number.

php --ini

Shows which config file PHP actually loaded. A (none) there means it never found your php.ini, which is why an extension you enabled appears to be ignored. php -m lists what is enabled.

macOS

1. Download Docker Desktop from docker.com and install it.
2. Open it once and let it finish starting. The whale in the menu bar stops animating when it is ready.

Done when: docker --version prints a version number.

docker run hello-world

Prints a paragraph starting Hello from Docker!. This is the check that counts: the version command works even when the engine behind it is not running.

Windows

1. Download Docker Desktop from docker.com and install it.
2. It installs WSL2 if you do not have it, which requires a restart. Save your work before starting.
3. After the restart, open Docker Desktop and let it finish starting.

Done when: docker --version prints a version number.

docker run hello-world

Prints a paragraph starting Hello from Docker!. This is the check that counts: the version command works even when the engine behind it is not running.

Linux

1. Install Docker Engine following the instructions for your distribution at docs.docker.com/engine/install. Docker Desktop exists for Linux but the Engine is the usual choice.
2. Add yourself to the docker group so you do not need sudo for every command, then log out and back in.

Done when: docker --version prints a version number.

docker run hello-world

Prints a paragraph starting Hello from Docker!. This is the check that counts: the version command works even when the engine behind it is not running.

macOS

1. Run brew install postgresql@18. Pin the major version rather than installing bare postgresql, so a later brew upgrade cannot move your data directory out from under you.
2. Start it. Homebrew installs the service without starting it, and this is a separate command that gets skipped constantly.

brew install postgresql@18brew services start postgresql@18

Done when: psql --version prints a version number.

psql -d postgres -c "select version();"

The version check only proves the client program exists. This one proves the server is running and accepting connections, which is the thing you actually need.

Windows

1. Download the installer from enterprisedb.com. It bundles pgAdmin, which is a usable graphical client.
2. Partway through it asks for a superuser password. Write it down now. There is no way to recover it later.
3. Leave the port at 5432 unless you know something else is using it.

Done when: psql --version prints a version number.

psql -d postgres -c "select version();"

The version check only proves the client program exists. This one proves the server is running and accepting connections, which is the thing you actually need.

Linux

1. Install and enable it with the commands below.
2. On Debian and Ubuntu the install creates a postgres system user, and your first connection goes through it rather than through a bare psql.

sudo apt update && sudo apt install postgresqlsudo systemctl enable --now postgresqlsudo -u postgres psql

Done when: psql --version prints a version number.

psql -d postgres -c "select version();"

The version check only proves the client program exists. This one proves the server is running and accepting connections, which is the thing you actually need.

macOS

1. Run brew install mysql, then start it. As with PostgreSQL, starting it is a separate command.
2. Run mysql_secure_installation. Homebrew installs MySQL with no root password at all, which is convenient and not a state to leave a machine in.

brew install mysqlbrew services start mysqlmysql_secure_installation

Done when: mysql --version prints a version number.

mysql -u root -p -e "select version();"

Prompts for the root password, then proves the server is up and your credentials work. A version check alone proves neither.

Windows

1. Download the MySQL Installer from dev.mysql.com and run it.
2. It asks for a root password. Write it down now.
3. It asks about the authentication method. The current default is the stronger one and is correct for anything new. Pick the legacy option only if you already know the codebase you are connecting needs it.

Done when: mysql --version prints a version number.

mysql -u root -p -e "select version();"

Prompts for the root password, then proves the server is up and your credentials work. A version check alone proves neither.

Linux

1. Install and secure it with the commands below.
2. Many distributions ship MariaDB under the mysql command name. Check what mysql --version actually reports if you specifically need MySQL.

sudo apt update && sudo apt install mysql-serversudo systemctl enable --now mysqlsudo mysql_secure_installation

Done when: mysql --version prints a version number.

mysql -u root -p -e "select version();"

Prompts for the root password, then proves the server is up and your credentials work. A version check alone proves neither.

macOS

1. The sqlite3 command is already there. Skip to the check below.

Done when: sqlite3 --version prints a version number and a date.

python3 -c "import sqlite3; print(sqlite3.sqlite_version)"

If you reach SQLite through a language rather than the shell, this is the check that matters. The PHP equivalent, php -r "new PDO('sqlite::memory:'); echo 'PDO SQLite OK';", proves in one command that PHP is installed, on the PATH, loading the right config file, and has the driver enabled.

Windows

1. Run winget install SQLite.SQLite, or download the precompiled command-line tools from sqlite.org and add that folder to your PATH.
2. Only do this if you want the standalone shell. If you are reaching SQLite through Python or PHP, you already have it.

Done when: sqlite3 --version prints a version number and a date.

python3 -c "import sqlite3; print(sqlite3.sqlite_version)"

If you reach SQLite through a language rather than the shell, this is the check that matters. The PHP equivalent, php -r "new PDO('sqlite::memory:'); echo 'PDO SQLite OK';", proves in one command that PHP is installed, on the PATH, loading the right config file, and has the driver enabled.

Linux

1. Run sudo apt install sqlite3 if the command is missing, which it usually is not.

Done when: sqlite3 --version prints a version number and a date.

python3 -c "import sqlite3; print(sqlite3.sqlite_version)"

If you reach SQLite through a language rather than the shell, this is the check that matters. The PHP equivalent, php -r "new PDO('sqlite::memory:'); echo 'PDO SQLite OK';", proves in one command that PHP is installed, on the PATH, loading the right config file, and has the driver enabled.