Alan Turing needs money and decides to sell lottery tickets. As demand grows, he hires others to help. To improve efficiency, Turing has the resellers wait in a line for tickets and later prints batches of tickets for them in advance so they don't have to keep returning to him. The final system has Turing as the single source of true information and data orchestrator, with pre-generated tickets, multiple resellers acting as data processors, and a job queue to handle customers in a first-in, first-out order for horizontal load balancing.

1. System Design Basics
(Lottery Ticket)
Md Imran Hasan Hira
Software Developer, Booking.com

2. The situation
Alan Turing needs some help.
He is out of money and he is looking for a work.

3. The stupid solution
Alan Turing needs some help.
He is out of money and he is looking for a work.
So he decided to sell lottery ticket and earn some
money around that.

4. Alan Turing is selling lottery ticket
Alan TuringLottery Ticket
Customers

5. Turing became popular
Alan TuringLottery Ticket
More Customers

6. Turing's ticket booth became super popular
Alan TuringLottery Ticket
Excessive Customers

7. At some moment, Turing feeling like...
Lottery Ticket
Excessive Customers
কাস্টমারেে ***
দাাঁ ড়ারে পােছিনা

8. So, Turing recruited some people for him
Lottery Ticket
Excessive Customers
Alan Turing
T.B. Lee G. Hopper D. Knuth
J.V.
Neumann

9. Things were running fine, but then more customers
came
Lottery Ticket
Super Excessive Customers
Alan Turing
T.B. Lee G. Hopper D. Knuth
J.V.
Neumann

10. Turing came up with this idea to put them in line
Lottery Ticket
Customers waiting in to get service
Alan Turing
T.B. Lee G. Hopper D. Knuth
J.V.
Neumann
...
...
...
...

11. With too many people in the line, the ticket resellers
were unnecessarily going back and forth to Turing
Lottery Ticket Alan Turing
T.B. Lee G. Hopper D. Knuth
J.V.
Neumann...
...
...
...

12. So, Turing printed a bunch of tickets and give them
to resellers upfront, so that they can save time
All Lottery Tickets Alan Turing
T.B. Lee G. Hopper D. Knuth
J.V.
Neumann
...
...
...
...
Lottery Ticket Lottery Ticket Lottery TicketLottery Ticket

13. And the final design looks like this
All Lottery Tickets
Alan Turing
T.B. Lee G. Hopper D. Knuth
J.V.
Neumann
...
...
...
...
Lottery Ticket Lottery Ticket Lottery TicketLottery Ticket

14. System design terminologies
All Lottery Tickets
Alan Turing
T.B. Lee G. Hopper D. Knuth
J.V.
Neumann
...
...
...
...
Lottery Ticket Lottery Ticket Lottery TicketLottery Ticket
Source of true Information
Data Orchestrator
Pre-Generated Content
Data Processor
Job queue (FIFO)
Horizontal Load Balancing

15. Thank You :)