From the source
Block builds tools that help businesses and individuals participate in the economy, including Square for sellers and Cash App for consumers.
Bradley Axen leads AI capabilities at Block, where his team builds end-to-end AI products, including Buzz, an open-source workspace for human-agent teams (opens in new tab) , and partners with the Square and Cash App teams to build customer-facing AI features.
Brad spoke with Anthropic about how frontier models like Claude Opus 5 and Claude Fable 5 have transformed what it means to be an engineer, how Block applies agent orchestration patterns with Fable, and the role of safeguards when every employee has access to frontier models.
Frontier models have made meaningful progress in 2026.
How has this technology impacted how you work?
The biggest impact AI has had on our work at Block is how we build things, and you couldn't overstate how impactful that is.
We saw the beginning of it in 2025 with tools like Claude Code, which at the time, required a lot more manual intervention.
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