Try Without Microcontroller

BlueScript is designed primarily for microcontroller development (ESP32). If you do not have hardware yet—or want a faster path for language and compiler checks—you can run BlueScript on the host runtime on your development machine.

For the main ESP32 workflow, see Get Started.

Prerequisites

Quickstart

1. Install the CLI

If you have not installed the CLI yet:

git clone https://github.com/csg-tokyo/bluescript.git
cd bluescript
npm install
npm run build:all
cd cli
npm link

info

The Next version is not released yet, so it cannot be installed from npm. For the released package, switch to the latest version (2.1.x).

On Windows, install the Visual C++ Build Environment before running this command.

2. Set up the host runtime

bscript board setup host

3. Create a host project

bscript project create hello-host -b host
cd hello-host

4. Write your program

Edit src/index.bs:

src/index.bs

console.log("Hello from host runtime!");

5. Run

bscript project run

You can also start interactive mode:

bscript project run --with-repl
# or
bscript project run --with-notebook

Notes

• bscript board flash-runtime is for microcontrollers and is not supported for host.
• GPIO and other ESP32-specific libraries are not available on host.

Host vs ESP32

Topic	Host (-b host)	ESP32 (-b esp32)
Main use case	Fast local testing	Real hardware development
Runtime location	Local process on the development machine	Runtime on the microcontroller
Setup	bscript board setup host	bscript board setup esp32 + bscript board flash-runtime esp32
Connection during run	Local process	Bluetooth
-d / --device-name	Not used	BLE device name to connect to (must match flash-runtime)
Hardware libraries (GPIO, PWM, I2C)	Not available	Available via packages
flash-runtime	Not supported	Required for first-time setup

Choose ESP32 if you are building applications for real devices. Choose host if you want a no-hardware path for syntax checks, compiler behavior checks, or CI-like validation.