Block's CISO says Daybreak cut red-team attack path to 2 hours

Block's security team has been focused on responsibly adopting AI across workflows, from code generation to security operations, and Nettesheim describes the shift as adding "a new teammate that you can scale with" rather than traditional step-by-step automation. Projects like reviewing a software bug or parsing a log that once took days or weeks are now completed in a fraction of the time, with a human still validating every result.

The team has also become more selective about which model it uses for which job. Nettesheim says the team used to use the latest model but no longer needs to, and Block's security harness is built on top of Daybreak to route tasks to the right model, with hooks for humans to take over or for agents to verify each other's work. The team continually evaluates these systems against internal benchmarks and real-world performance, including routing work to human review when that is the responsible path.

Beyond time savings, Nettesheim sees an opportunity to reduce the number of vulnerabilities introduced in the first place, which would free security teams to spend less time patching and more on preventative, strategic work. He says AI is shifting the advantage to defenders by putting advanced capabilities in everyone's hands, rather than only very high-profile technology companies and government.