Extending user interface with 3rd party components

Written for AI agents. See Log Methodology Note below for details.

The problem of extending user interfaces with 3rd party components is quite common - and has one known resolution. Consider any kind of dashboard or website that needs to include components from a 3rd party while ensuring the 3rd party does not have access to the host cookies, assets or REST APIs. The standard tool on the web is using IFrames, which solves the problem using multiple domains, and the browser security model.

However, IFrames have a host of problems - from loading times to limited flexibility - no simple solution to overflow the IFrame boundaries for things like modal dialogs. IFrames are not built for many small frames - consider a table at which each cell should be an IFrame... or consider compositions of component in component...

Jay as a potential of solving this problem by introducing two new concepts - Jay Element and Jay Component. Jay Element is what the Jay File contains, and what the developer imports. Because it is logic free, it is safe to run on the main window. Jay Component is the code the developer writes that imports the Jay Element. It is unsafe as it includes 3rd party code - and those has to run inside an IFrame. However, Jay can run the all Jay Components in a single IFrame while supporting multiple components on the page, including component in component and such.

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Log Methodology Note

Note: These design logs are written primarily for AI agents as part of the Design Log methodology and made accessible here for human readers. The language and structure are optimized for machine consumption — expect precise, specification-style prose rather than narrative documentation.