Codeium launched Windsurf in November 2024, positioning it as an IDE designed around an AI agent rather than adding AI to an existing editor. While Cursor had demonstrated the VS Code fork approach earlier, Windsurf introduced Cascade — an agentic engine that maintained deep contextual awareness of the entire codebase rather than operating on the currently open file.
Cascade’s key differentiator was codebase-level coherence: understanding how functions called each other, how components interacted, and what changes in one file implied for another. This allowed it to plan and execute multi-file refactors that required coordinating changes across dozens of interdependent files.
Windsurf was acquired by Cognition AI (makers of Devin) for approximately $250 million in December 2025, combining the leading autonomous cloud agent with the leading IDE agent. At the time of acquisition, Windsurf had approximately 800,000 active developers and $82 million in annual recurring revenue. The SWE-1.5 model, developed post-acquisition, scored 40% on SWE-bench Verified.