# E0217: TypeScript interface methods cannot be marked 'async'

The `async` keyword on methods changes the body of that method. TypeScript interface methods do not have bodies. Therefore, `async` does not make sense on TypeScript interface methods, and it is a syntax error to write it:

    interface DataLoader {
      async load(): Promise<LoadedData>;
    }

To fix this error, remove the `async` keyword:

    interface DataLoader {
      load(): Promise<LoadedData>;
    }

Introduced in quick-lint-js version 2.6.0.

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