Harper

Offline, privacy-first grammar checker built in Rust

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Harper is an offline, open-source grammar checker built in Rust that gives context-aware English writing suggestions without sending any text to the cloud. It's aimed at writers and developers who want a fast, privacy-respecting alternative to cloud-based grammar checkers like Grammarly.

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Problem & pain-point mapping
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What it's a strong alternative to
Trust & credibility signals

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