Harper on a Mac
Offline, Rust grammar checker (LanguageTool alt.) · Tools
Harper (by Automattic — *not* HarperDB) is an offline, privacy-first grammar and style checker written in Rust — a fast local Grammarly/LanguageTool alternative. It ships as an LSP language server (harper-ls) for editors, plus a CLI, a WASM library, and browser/Obsidian integrations — a developer/writing tool, not a web service. Install with brew install harper. Apache-2.0.
Run Harper with FrontierStack
FrontierStack lists Harper in its Tools catalog. Install or connect it from one place, then monitor its status, ports and certificate, secure it with the firewall and Malware Audit, and back it up.
Run it all from one Mac app.
FrontierStack installs, monitors and secures the whole stack — locally and across your fleet — from a single native macOS app.
Download FrontierStack