Best AI Coding Assistants of 2026: Cursor AI vs Windsurf vs GitHub Copilot vs Aider Benchmark
We stress-tested Cursor, Codeium Windsurf, GitHub Copilot, and Aider on a real 5,000 LOC codebase. Here are the raw benchmarks for speed, multi-file diff accuracy, SWE-bench score, and total developer ROI in 2026.