Comparison · under IB-CODE-2026.2
Aider vs Windsurf
| Aider | Windsurf | |
|---|---|---|
| Vendor | Paul Gauthier (OSS, Apache 2.0) | Cognition (formerly Codeium) |
| Pricing | Free OSS + API tokens; $30-60/mo typical at moderate use with Sonnet 4.6 | Free 25 credits/mo; Pro $15/mo (500 credits); Teams $30/user/mo |
| Default model | Model-agnostic; community default claude-sonnet-4-6 or GPT-5.5; 100+ providers | SWE-1.5 (Cognition proprietary, trained with Devin's engineering stack); Claude/GPT switchable |
| CLI surface | ✓ | — |
| Eval status | queued | out of scope |
Comparison pending — neither side evaluated yet
Both Aider and Windsurf are currently unevaluated under IB-CODE-2026.2. This page will update as evaluations land.
Want this comparison sooner? Vendors can commission an evaluation to bump their tool up the queue (with full editorial independence on the verdict). Readers can email hello@indiebench.dev to vote for which comparison ships next.
About each tool
Aider
Aider is the reference implementation of BYOK CLI coding agents. Deepest git integration in the category: auto-commit per change, smart context windows from the repo map, reproducible CI runs. Pip-installable, model-agnostic, no telemetry. Star growth has slowed as OpenCode picks up community attent…
Windsurf
Windsurf is the agentic IDE acquired by Cognition (the Devin team) in late 2025. The Cascade multi-step engine is genuinely strong — but it is IDE-only, with no standalone CLI or SDK as of May 2026. This puts Windsurf out of scope for IB-CODE-2026.2 (autonomous CLI/API evaluation). When the upcoming…