Build me an API

Please Implement below API,

1. Registration service with /users endpoint for taking a JSON body with details such as,

FIELDS & VALIDATIONS
 Username - alphanumeric, no spaces
 Password – min length 8, at least one upper case letter & number
 Email – email id with email format
 DoB (Date of Birth) - ISO 8601 format
 Credit Card Number – This field is optional. If given should have 16 digits.
EXPECTED RESPONSES:
 If the request body fails to satisfy any of the basic validation checks return HTTP Status code: 400
 Reject requests if the user is under the age of 18 and return HTTP Status code: 403
 If the username has already been used reject the request and return HTTP Status code: 409
 A successful action should return HTTP Status code: 201

GET /users endpoint:
Consumer should be able to provide a filter (CreditCard=Yes/No) in his request. If “Yes” then should return Users registered with Credit Card Number.
If “No” then return Users registered without a Credit Card Number. Without any filter should return all the Registered Users.


2. Payment service with /payments endpoint for taking a JSON body with details such as,

FIELDS & VALIDATIONS
 Credit Card Number – 16 digits
 Amount – 3 digits

EXPECTED RESPONSES:
 If the request body fails to satisfy any of the basic validation checks return HTTP Status code: 400
 If credit card number is not registered against any Registered User return HTTP Status code: 404
 A successful payment should return HTTP Status code: 201

REQUIREMENTS:
 You are free to use any Programming Language or Framework you are comfortable with (Node.js express with nodemon?)
 Please include instructions for running the application
 We don’t need you to implement any Frontend code
 No need to use any Databases/in-memory Databases. You can use language provided data structures in place of that.
 We expect you to provide Unit Tests for your solution (Use postman)