Workers fetch requests now support cf.vary

June 28, 2026

Workers fetch requests now support cf.vary

Workers fetch() requests now support the cf.vary request option. Use cf.vary to control how Cloudflare caches origin responses with a Vary header for a single subrequest.

src/index.jsjs

export default {
	async fetch(request) {
		return fetch(request, {
			cf: {
				vary: {
					default: { action: "bypass" },
					headers: {
						accept: {
							action: "normalize",
							media_types: ["text/html", "application/json"],
						},
						"accept-language": {
							action: "normalize",
							languages: ["en", "fr", "de"],
						},
					},
				},
			},
		});
	},
};

src/index.tsts

export default {
	async fetch(request): Promise<Response> {
		return fetch(request, {
			cf: {
				vary: {
					default: { action: "bypass" },
					headers: {
						accept: {
							action: "normalize",
							media_types: ["text/html", "application/json"],
						},
						"accept-language": {
							action: "normalize",
							languages: ["en", "fr", "de"],
						},
					},
				},
			},
		});
	},
} satisfies ExportedHandler;

For more information, refer to cf.vary.