# Type Alias: AnyTRPCMiddlewareFunction

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> **AnyTRPCMiddlewareFunction**: `MiddlewareFunction`\<`any`, `any`, `any`, `any`, `any`\>

Defined in: [packages/server/src/unstable-core-do-not-import/middleware.ts:149](https://github.com/trpc/trpc/blob/57482b0bb09dce5c838dc8bf5727a943488bac61/packages/server/src/unstable-core-do-not-import/middleware.ts#L149)

Any middleware function, for use in generic constraints.