Building what's next (Interview)

Michael Grenich of WorkOS and Zeno Rocha of Resend discuss how software is being redesigned for AI agents as much as humans. They cover agent auth, identity, permissions, discoverability, and infrastructure choices like Resend’s Go rewrite, plus why developer experience is now shifting toward agent experience.

Key points

• WorkOS is building Pipes for safe agent data access, plus authorization and identity layers for agents across enterprise systems.
• Resend optimized first for developer experience, then added agent-friendly surfaces: CLI, MCP, .well-known OpenAPI JSON, and markdown pages.
• Resend moved broadcast-email processing to Go and AWS queues to improve concurrency and protect deliverability at billion-email scale.
• Inbound email is a major product push: users want inbox workflows, automation, and agent inboxes, not just sending.
• Resend keeps a generous free tier, but abuse prevention is now a major operational burden; it has 3 million users and 100,000 paying customers.
• Rocha is experimenting with closed-loop AI: downvotes from the in-app agent can trigger draft PRs and eval updates.