This document proposes a "boxcar" distributed computing system using event sourcing and Azure services like Event Grid and Storage to enable computations for low costs. It outlines sources of computing costs and introduces event sourcing concepts. The proposed system would use durable functions and event appending to Azure Storage for command handling and queries, with notifications between domains. Lessons learned include measuring performance, investing in design, and ensuring data can be read after writes.

1. “Boxcar” systems
Distributed computing for pennies

2. Agenda
• Sources of cost
• Introduction to “event sourcing”
• Introduction to Azure Event Grid / Azure storage
• Overview of a proposed system
• Lessons learned

3. Caveats

4. Sources of cost
Fixed costs Overprovisioning

5. Introduction to “event sourcing”

6. Introduction to Azure Storage
Cosmos Db
Append Blob
Tables
Files

7. Overview of a proposed system
League Race
Runner

8. Handling a command
Durable Function Orchestration
Command
Validations
Append
Event(s)

9. Handling a query
Durable Function Orchestration
Run
Projection
Return
Results
Query
Validations

10. Notifications and inter-domain
communication

11. Lessons learned
Don’t assume. Measure!
Invest time in design
Read your writes

12. Questions?
@Merrion