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What is the Aider Polyglot benchmark?
Last reviewed July 16, 2026
Aider Polyglot is a code-editing benchmark of 225 of the hardest Exercism exercises across 6 languages: C++, Go, Java, JavaScript, Python, and Rust. A model passes an exercise only when its edits are emitted in the expected format, apply cleanly to the files, and make the exercise's tests pass. It measures the practical skill coding agents live on: editing existing code reliably, not just generating snippets.
Why edit format matters
Agents change code by emitting structured edits (diffs or search-and-replace blocks) that tooling applies mechanically. A model that solves the problem but malforms its edit fails the task in practice, and this benchmark scores exactly that: correctness and format adherence together. It explains why some models that ace generation benchmarks frustrate in real editing loops.
Reading Polyglot scores
The exercises are the hardest of the Exercism sets, spread across 6 languages, so the score rewards breadth and discipline over single-language strength. Compare it with repository-scale results: SWE-bench Verified adds codebase navigation on top, while Polyglot isolates the edit mechanics.
Top models on Aider Polyglot
Full leaderboardPeak scores from the compiled benchmark data; reasoning models use their highest effort tier.
idapt's coding rankings include an Aider Polyglot lane, a useful signal when picking the model behind an editing agent; idapt agents apply file edits through the same structured-edit discipline the benchmark tests.
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