The Billing Cycle
What's the Billing Cycle?
Group of twelve tasks that are executed every month, in sequential order, to collect the money from customers for the usage of our service
1. Create invoices
2. Send invoices
3. Send credit notes
4. First charge attempt
5. Send reminders
6. Send credit notes
7. Second charge attempt
8. Send reminders
9. Send credit notes
10. Third charge attempt
11. Send credit notes
12. Encash
1.
2. Send invoices
3. Send credit notes
4. First charge attempt
5. Send reminders
6. Send credit notes
7. Second charge attempt
8. Send reminders
9. Send credit notes
10. Third charge attempt
11. Send credit notes
12. Encash
Create invoices
Make Invoice Generation
Great Again
Problems
- Consistency
- Relieability
- Speed
- Visibility
duplicated invoices, wrong amount of invoices
duplicated invoices, wrong amount of invoices
process takes too much time
There is no way to understand what it the state of the process. Completed? Errors? In progress?
Invoice Numbers
- Generated sequentially per company
- If an invoice number exists, all previous consecutive numbers should also exists!
N = 100
1, 2, 3, 4, 5, ..., 99
Too much talk, let's draw something
Consistent
Reliable
Fast
Visible
*
*
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fixed time deadline
-
limited human resources
Consistency
- Ensure no duplicated invoices can be created per company, year, month and customer.
- Ensure each ride is charged only once.
Reliability
- Ensure number of generated invoices don't change per billing period.
- Generation of single invoice idempotent
Speed ⚡️
The "Draft" Invoice
Like an Invoice but without the invoice number 😏
1. Invoice creation (draft).
2. Invoice number assignment (invoice).
let's draw a bit more...
Visibility 👁🗨
Invoice Generation
October 2019
- 33,792 invoices generated in around 1 hour and 15 minutes
- Draft invoices creation took less than 15 minutes.
- Invoice number assignment took around 1 hour.
Learnings...
Avoid at all cost, fixed strong deadlines. They are evil.
👿
- Burn people out.
- Increase stress level.
- Open the door to low quality work.
Further Optimization
Let's burn it and use an external provider
