Typescript Issue with Optional Decoder Function

import { Context, Effect as E, Layer, pipe } from "effect";

export class Storage extends Context.Tag("Storage")<
  Storage,
  {
    readonly set: (key: string, value: string) => E.Effect<void, Error>;
    readonly get: <T>(key: string, decode: (value: string) => T) => E.Effect<T, Error>;
  }
>() {}

export const StorageLive = Layer.succeed(
  Storage,
  Storage.of({
    set: (key, newValue) => {
      return E.try({
        try: () => window.localStorage.setItem(key, newValue),
        catch: (cause) => Error("An error occured storing data.", { cause }),
      }).pipe(E.tap(() => window.dispatchEvent(new StorageEvent("storage", { key, newValue }))));
    },
    get: (key, decode) => {
      return pipe(
        E.fromNullable(window.localStorage.getItem(key)),
        E.match({
          onFailure: (cause) => Error(`No data found matching key ${key}`, { cause }),
          onSuccess: (value) => (decode ? decode(value) : value),
        }),
      );
    },
  }),
);