Stocks trading service using volatility decomposition

Instead of looking at a Stocks trading service using functional decomposition, let’s instead look at doing some #Volatility decomposition to design a stock trading system.

Let’s investigate the volatilities.


  • Types of users: Power users, casual users, sysadmins, robots, executives
  • Authentications
  • Notifications
    • Delivery: Email, SMS, fax
    • Recipients: Boss, coworkers, custom list of emails, department
    • Fallback procedures
  • Storage of data
    • Local DB / remote DB
    • Data replication (redundancy)
    • Caching
  • Connectivity, async vs sync
    • Recovery
    • Out of order
  • Jumping platforms
    • Work comp. -> phone on train -> PC at home
    • Duration of interactions
  • Locality
    • Rules per locales
  • Stock provider
    • Data feed
    • Content
    • Real vs simulated
    • Frequency
    • Format
  • And much, much more…

This is a non-exhaustive list of the volatilities. This is just to give some concrete samples of volatilities.


  • J. Löwy (January 27, 2021), “Righting Software - System Design” [Workshop], NDC London 2021.