Replit dropped a double announcement on March 11: a $400 million Series D and the launch of Agent 4, its most capable coding agent yet. The round triples the company's valuation to $9 billion in just six months, with backing from a16z, Craft Ventures, Databricks Ventures, Georgian, Prysm Capital, and others — plus celebrity investors Shaquille O'Neal and Jared Leto.

Agent 4: Parallel Builds, Infinite Canvas

Agent 4 is built around four pillars. Design Freely lets you explore UI variants on an infinite canvas while the agent builds in the background. Move Faster deploys parallel sub-agents to tackle auth, databases, front-end, and back-end simultaneously — all visible in a single dashboard. Ship Anything unifies web apps, mobile apps, landing pages, decks, and more in one project with shared design context. Build Together handles multi-person teams by intelligently sequencing requests submitted in any order.

CEO Amjad Masad framed the shift plainly: software isn't merely technical work anymore — it's creative. Agent 4 follows Agent 3's push on pure autonomy (self-testing, hours-long unattended runs) and adds human creative collaboration as the next layer.

Scale and Ambitions

Replit claims users from 85% of Fortune 500 companies are already building on the platform, and is targeting $1 billion in annual revenue by end of 2026. With Agent 4 now available to all users, the race to make programming truly accessible — not just assisted — is entering its most competitive phase yet.