Discord Lambda lets you create web content that has Discord meta information, so that its link is displayed as a nice preview thumbnail when pasted into a Discord channel. You can also add your logo to the preview.
https://discordlambda.netlify.app/
git clone --recurse-submodules https://github.com/hyperchessbot/discordlambda
Build needs Netlify CLI and rollup.js . Install them as follows
npm install -g netlify-cli
see also https://docs.netlify.com/cli/get-started/
npm install -g rollup
see also https://rollupjs.org/guide/en/
rollup -c
netlify build
NETLIFY_AUTH_TOKEN
Generate in User Settings / Applications.
NETLIFY_SITE_ID
Look up in Site Details.
rollup -c -w  &
netlify dev &
start rollup -c -w
start netlify dev