Fully local code embeds

April 20, 2026

Aleksandr Hovhannisyan built a web component that renders isolated code sandboxes using <iframe srcdoc>, without relying on third-party services like CodePen or CodeSandbox. The component takes HTML, CSS, and JavaScript from a template element and produces a fully local, isolated preview. It works anywhere HTML and JavaScript are supported and has zero dependencies.

aleksandrhovhannisyan.com/blog/local-code-embeds

Tags html js

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