Quickstart

From an empty folder to a running project.

Quickstart

This page goes from nothing to running code. The examples run MicroStudio from a checkout as microstudio; microstudio in its place is the same command.

If you have not installed it yet, see Installation.

Run three lines of Luau

No Rojo file is needed, and nothing is read from disk. Instance.new, game, workspace, Players, the datatypes and task are all in scope:

microstudio -e "
  local part = Instance.new('Part')
  part.Name = 'Probe'
  part.Parent = workspace
  print(part:GetFullName(), typeof(part.Position))
"

game.Workspace.Probe Vector3

Run a file, stdin, or a prompt

microstudio script.luau     # a file
microstudio -               # a script on stdin
microstudio                 # a prompt, on a fresh world

A script is treated as a program: when its entry chunk returns, so does MicroStudio — after the work the script scheduled finishes.

microstudio -e "
  task.spawn(function() task.wait(0.25) print('background finished') end)
  print('started')
"

started
background finished

At the prompt, bare expressions echo their value:

MicroStudio 1.1.1 — Luau 0.740 — :help for commands
> workspace
Instance<Workspace> Workspace
> Instance.new("Part").Size
4, 1, 2
> CFrame.Angles(0, math.pi / 2, 0)
0, 0, 0, 0, 0, 1, 0, 1, 0, -1, 0, 0
> game:GetService("CollectionService"):GetTags(workspace)
[]

See The REPL for the prompt's commands.

Boot the bundled example

examples/hello is a small project with a Rojo file, a server script and a shared module. dev reads the project, loads the compiled Luau into a live DataModel and runs the server scripts:

microstudio dev examples/hello --once

MicroStudio dev — .../examples/hello/default.project.json
loaded 6 instances
hello, MicroStudio
running on the server: true
tagged a checkpoint: Checkpoint1
checkpoint position: 0, 0, 0
tagged instances: 1
util.sum: 6
[server] ServerScriptService.TS.game

Use it as a boot check

dev uses a real clock, so task.wait(0.5) really waits. dev --once boots the project, drives it for --timeout seconds (0.1 by default) and exits non-zero if anything errored. This is the "does my project still boot" check for CI:

microstudio dev examples/hello --once --timeout 3

MicroStudio dev — .../examples/hello/default.project.json
loaded 6 instances
hello, MicroStudio
running on the server: true
tagged a checkpoint: Checkpoint1
checkpoint position: 0, 0, 0
tagged instances: 1
util.sum: 6
[server] ServerScriptService.TS.game

For assertions rather than a boot check, use microstudio test.

Stay in the world, or re-run on save

Add --interactive to run a file and stay in the world it created, or --watch to re-run on save, like a Luau scratchpad:

microstudio script.luau --interactive
microstudio script.luau --watch
microstudio script.luau --interactive --watch

dev accepts both flags too. Continue with Running a project for the full dev workflow.