SuperTokens is an open source authentication solution offering features like: Different types of login: Email / password, Passwordless (OTP or Magic link based).

SuperTokens.com

So change the assignment of `recipeInstance` to:
```js
app.post("/auth/signup", async (req, res) => {

  let recipeInstance = ThirdPartyEmailPasswordRaw.getInstanceOrThrowError().emailPasswordRecipe;

  // TODO: This will handle sign up requests from email password login. The body for this can be found here: https://github.com/supertokens/supertokens-node/blob/master/lib/ts/recipe/emailpassword/api/signup.ts
})

app.post("/auth/signinup", async (req, res) => {

    let recipeInstance = ThirdPartyEmailPasswordRaw.getInstanceOrThrowError().thirdPartyRecipe;

  // TODO: This will handle sign up and in requests from social login. The body for this can be found here: https://github.com/supertokens/supertokens-node/blob/master/lib/ts/recipe/thirdparty/api/signinup.ts
})
```