Configure a Cally view, preview the resulting markup, and copy it into your website.
<script async src="https://cally.fyi/embed/view/v1.js"></script>
<cally-view cally-id="" view="timeline"></cally-view>Allow https://cally.fyi in both script-src and connect-src.
Content-Security-Policy: default-src 'self'; script-src 'self' https://cally.fyi; connect-src 'self' https://cally.fyi; style-src 'self' 'unsafe-inline'