The REPL

The mxcli REPL is an interactive shell for working with Mendix projects, much like psql is for PostgreSQL or mysql for MySQL. You type MDL statements, press Enter, and see results immediately.

Starting the REPL

Launch it with or without a project:

# Start with a project already loaded
mxcli -p app.mpr

# Start without a project (you can open one later)
mxcli

You’ll see a prompt where you can start typing MDL:

mxcli>

Running commands

Type any MDL statement and press Enter:

SHOW MODULES;

Results are printed as formatted tables directly in the terminal.

Multi-line statements

MDL statements end with a semicolon (;). If you press Enter before typing a semicolon, mxcli knows you’re still writing and waits for more input:

CREATE ENTITY MyModule.Customer (
    Name: String(200) NOT NULL,
    Email: String(200),
    IsActive: Boolean DEFAULT true
);

The REPL shows a continuation prompt (.....>) while you’re in a multi-line statement. The statement executes when you type the closing ; and press Enter.

Getting help

Type HELP to see a list of available commands:

HELP;

This prints a categorized overview of all MDL statements – useful when you can’t remember the exact syntax for something.

Command history

Use the up and down arrow keys to scroll through previous commands, just like in any other shell. This is especially handy when you’re iterating on a query or tweaking a CREATE statement.

One-off commands with `-c`

You don’t always need an interactive session. The -c flag lets you run a single command and exit:

mxcli -p app.mpr -c "SHOW ENTITIES IN MyModule"

This is great for quick lookups and for scripting. The output is pipe-friendly, so you can chain it with other tools:

# Count entities per module
mxcli -p app.mpr -c "SHOW MODULES" | tail -n +2 | while read module; do
    echo "$module: $(mxcli -p app.mpr -c "SHOW ENTITIES IN $module" | wc -l) entities"
done

Running script files

For anything beyond a quick one-liner, you can put MDL statements in a .mdl file and execute the whole thing:

mxcli -p app.mpr -c "EXECUTE SCRIPT 'setup.mdl'"

Or from the REPL:

EXECUTE SCRIPT 'setup.mdl';

This is how you’ll typically apply larger changes – write the MDL in a file, check the syntax with mxcli check, then execute it.

The TUI (Terminal UI)

If you prefer a more visual experience, mxcli also offers a graphical terminal interface:

mxcli tui -p app.mpr

The TUI gives you a split-pane layout with a project tree, an MDL editor, and output panels. It’s built on top of the same REPL engine, so all the same commands work. This can be a nice middle ground between the bare REPL and opening Studio Pro.

What’s next

Now that you know how to install mxcli, open a project, and use the REPL, you’re ready to start exploring. The next chapter walks through the commands you’ll use most often: SHOW, DESCRIBE, and SEARCH.

mxcli Documentation