Harper
Apache-2.0 offline privacy grammar checker — Rust (Automattic)
Rust / Editors · Apache-2.0 · 16.7k
Reviewed 2026-09-15 · last push 2026-10-19 · repo checked 2026-10-19
What's Good
Apache-2.0 (Automattic/harper). Local grammar/style checking with editor/LSP/Obsidian integrations. Docs and product at writewithharper.com. Runs on your machine; aimed at writers who refuse to paste drafts into SaaS grammar boxes.
The Catch
Vs Grammarly SaaS: Harper is offline Rust grammar, not a cloud writing coach with tone/generative rewrites and team admin. Rule coverage and language support differ from Grammarly’s product surface — try it on your real prose. Not an LLM writing agent.
Verdict
Apache-2.0 offline grammar. Privacy-local vs Grammarly cloud.
Embed
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Markdown
[](https://stackgems.com/gems/harper)
HTML
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