The `public/` directory that `gatsby build` produces. The entry `index.html` becomes the report body and the JS, CSS, fonts and images upload as assets with their references rewritten.

Does Gatsby's client-side routing work at the link?

Navigation between prerendered pages works, since each route has its own HTML file in the build. Scripts run inside a sandboxed iframe, so React hydration and interactive components behave normally.

What about the image plugin and GraphQL?

gatsby-plugin-image processes images at build time, so the generated variants are in `public/` and upload with everything else. GraphQL runs at build time only — there is no runtime query to break.

Why publish rather than deploy a preview?

For the cases where a preview deploy is not available or not appropriate: a fork without secrets, a client review before the hosting decision is made, or a preview you want password-protected rather than public.

Can the same link show the next build?

Yes — PATCH the same report id. The reviewer's URL shows the current build with earlier ones kept as revisions, and their comment threads carry across.

Share a Gatsby site preview

gatsby build produces public/, a complete static site, and then the review turns into an infrastructure question. Which is a strange outcome for a directory of files whose entire purpose is to be served by anything.

Publish the build

gatsby build

Drag public/ (or a zip of it) into the app:

index.html becomes the report body.
JS, CSS, fonts and the build-time image variants upload as assets with their references rewritten to the uploaded copies — the step that separates a working preview from a page with broken CSS.
Scripts run inside a sandboxed iframe, so hydration, the nav and client-side transitions between prerendered routes keep working.

Leave pathPrefix unset for a preview build. It bakes in a path the preview is not being served under.

Private by default

Every report is private until you change it: team, email-domain gate, named reviewers, or a password-protected link for a client. See the sharing model. Which is a thing a quick static deploy usually does not give you without extra work.

Feedback lands on the page

The point of a preview is corrections, and corrections in an email are a to-do list you have to translate back into locations.

Anchored threads on the paragraph, the image, the nav item — see commenting on HTML.
Revisions. Rebuild, PATCH the same report id, and the reviewer sees the new build at the URL they already have.
An agent can read the comments back through MCP when the edits are being made by Claude Code rather than you.

Limits

Entry HTML: 5 MB. Assets: 25 MB per file, 250 MB and 500 files total — a Gatsby build with responsive image variants generates a lot of files and passes 500 easily on a media-heavy site. Build a subset for review when it does.
60 requests/minute per token.

Try it

Comma is free — unlimited reports, unlimited commenters, unlimited revision history.

Create your first report →