This is the simplest Fable application you can make: it is a frontend web application with an empty page that writes Hello from Fable to the console.

This template is not for production use and is only used to demonstrate Fable features in The Elmish Book

Requirements

• dotnet SDK v6.0 or later
• Node.js runtime

To compile the project, first you need to restore dotnet tools which bring it the Fable compiler

dotnet tool restore

Then run the following commands to install Node.js dependencies such as webpack and bundle the application

npm install
npm run build

npm install will install dependencies from npm which is the Node.js equivalent of dotnet's Nuget registry. These dependencies include the Fable compiler itself as it is distributed to npm to make compilation workflow as simple as possible.

npm run build is an alies for "compile with Fable, then bundle with webpack"

After npm run build finished running, the generated javascript will be bundled in a single file called main.js located in the dist directory along with an existing index.html page that references that script file.

While developing the application, you don't want to recompile the application every time you make a change. Instead of that, you can start the compilation process in development mode which will watch changes you make in the file and re-compile automatically really fast:

npm install
npm start

If you already ran npm install then you don't need to run it again. npm start will start the developement mode by invoking webpack-dev-server: the webpack development server that starts a lightweight local server at http://localhost:8080 from which the server will serve the client application