Reposting the comment as top level, as I haven't seen it mentioned anywhere. Google has developed Signed HTTP Exchanges https://developers.google.com/web/updat

Reposting the comment as top level, as I haven't seen it mentioned anywhere. Google has developed Signed HTTP Exchanges https://developers.google.com/web/updates/2018/11/signed-exchanges https://developers.google.com/web/updates/2018/11/signed-exc... that can then be bundled https://web.dev/web-bundles/ https://web.dev/web-bundles/ . Its main motivation is the rehosting of AMP pages while verifying that the cache hasn't tampered with them; but it could be extended to sign and bundle API calls for redistribution if needed.