5-Minute Quickstart

Get from zero to modifying a Mendix project in 5 minutes. No prior MDL knowledge needed.

1. Install mxcli

Option A: Zero install (Playground)

Open the mxcli Playground in a Codespace – mxcli, a sample project, and example scripts are pre-installed. Skip to step 3.

Option B: Binary download

Release assets are raw binaries named mxcli-<os>-<arch> (nothing to extract). Use the rolling nightly build while mxcli is alpha:

# macOS / Linux
curl -fsSL -o mxcli \
  https://github.com/mendixlabs/mxcli/releases/download/nightly/mxcli-linux-amd64
chmod +x mxcli && sudo mv mxcli /usr/local/bin/

Option C: Build from source (Go + Make)

git clone https://github.com/mendixlabs/mxcli.git && cd mxcli && make build
# binary at ./bin/mxcli  (go install @latest doesn't work — see Installation)

Verify: mxcli --version should print the version number.

See Installation for all options including Dev Containers.

2. Open your project

mxcli -p /path/to/your-app.mpr

You’ll see:

Connected to: your-app.mpr (Mendix 11.6.3)
MDL REPL - Mendix Definition Language
mdl>

Don’t have a Mendix project? Create one with mxcli new test-app --version 11.8.0 — this downloads MxBuild, creates a blank project, and sets up all tooling automatically.

3. Explore what’s there

-- List all modules
LIST MODULES;

-- List entities in a module
LIST ENTITIES IN MyFirstModule;

-- See the full structure at a glance
DESCRIBE STRUCTURE;

4. Create something

-- Create a new entity
CREATE PERSISTENT ENTITY MyFirstModule.Customer (
  Name: String(200) NOT NULL,
  Email: String(200),
  IsActive: Boolean DEFAULT true
);

Expected output:

Created entity: MyFirstModule.Customer

5. Verify it works

-- See what you created
DESCRIBE ENTITY MyFirstModule.Customer;

Output:

@Position(100, 100)
create or modify persistent entity MyFirstModule.Customer (
  Name: String(200) not null,
  Email: String(200),
  IsActive: Boolean default true
);

Open the project in Studio Pro – your entity is there.

6. Create a microflow

CREATE MICROFLOW MyFirstModule.ACT_DeactivateCustomer (
  $Customer: MyFirstModule.Customer
)
BEGIN
  CHANGE $Customer (IsActive = false);
  COMMIT $Customer;
END;

7. Validate

# Check your project for errors (from a separate terminal)
mxcli check -p /path/to/your-app.mpr

No errors? You’re done. Open in Studio Pro and everything is there.

What’s next?

Common issues

“mx command not available” – Install mxbuild for validation:

mxcli setup mxbuild -p your-app.mpr

“CGO not available” – mxcli uses pure Go SQLite. No C compiler needed. If you see CGO errors, ensure you’re using the official pre-built binary or a make build from source.

“refusing to write …: Studio Pro has this project open” – Close the project in Studio Pro before running mxcli write commands, then reopen it. Studio Pro does not reload the model from disk, so its next save would silently discard mxcli’s changes. If Studio Pro is not running, the .mpr.lock was left behind by a crash: delete it, or pass --force to exec.