Tutorial track A at #BOBkonf2026 continues after a tea break with @shibayashi 's "Illegal States Are My Favorite Security Vulnerabilities (to Delete at Compile Time)", where he demonstrates how we can model business workflows and constraints with types.

Find out more: https://bobkonf.de/2026/koppmann.html

BOB - Illegal States Are My Favorite Security Vulnerabilities (to Delete at Compile Time)

BOB Konferenz, Best of Breed Konferenz für Software-Entwickler und Entscheider in der Softwareentwicklung.

@bobkonf @shibayashi Heck yeah! I consider using a type-first programming approach with strong constraints as one of the best things you can do for application security. Not everything needs to be "a string". Modeling your problem domain in types is helpful in so many ways!
@ljrk @bobkonf I absolutely agree. We should all be nicer to our compilers. They are our friends!