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Compatibility Dates

• Compatibility Dates Reference

Miniflare uses compatibility dates to opt-into backwards-incompatible changes from a specific date. If one isn't set, it will default to some time far in the past.

const mf = new Miniflare({
	compatibilityDate: "2021-11-12",
});

Miniflare also lets you opt-in/out of specific changes using compatibility flags:

const mf = new Miniflare({
	compatibilityFlags: [
		"formdata_parser_supports_files",
		"durable_object_fetch_allows_relative_url",
	],
});