For this guide, we’ll use a minimal Next.js app as an example, but any Next.js app should work fine. You can find the complete source code used in this demo here. To get started, download the latest version of Subtrace using the following command: 
curl -fsSL https://subtrace.dev/install.sh | sh
Then get a SUBTRACE_TOKEN from the Subtrace dashboard for free and set it as an environment variable. 
# get a tracer token for free at https://subtrace.dev/dashboard
export SUBTRACE_TOKEN=
Build and start your server using Subtrace: 
npm install
subtrace run -- npm run dev
That’s it! You can now visit localhost:3000 to see them automatically appear in the Subtrace dashboard in realtime.