Show HN: Charm – on-device spelling, grammar, and prediction for macOS

Spelling, grammar, and word prediction for every Mac app. Launch price: $9.99, yours forever.
3 points by theodorehq 153 days ago www.theodorehq.com 1 comments
Summary not yet generated for this article.

Original Text

I've spent the last year building Charm, a native macOS menu bar app that corrects spelling, fixes grammar, and predicts your next word.

Three features:

- Spells: NSSpellChecker plus a local LLM for context-aware corrections (catches "definately" -> "definitely" without the false positives macOS autocorrect is known for). - Polish: sentence-level grammar fixes triggered at punctuation boundaries. - Oracle: next-word prediction, Tab to accept.

100% local. Choose Gemma 2 2B or Qwen 2.5 3B; the model downloads once from HuggingFace on first use, then everything runs on your Mac. No cloud option exists, no accounts, no API keys, no telemetry. The model auto-unloads after 5 minutes idle so the RAM cost is bounded.

Built in Swift / SwiftUI. Needs Accessibility and Input Monitoring permissions because text replacement requires reading keystrokes globally. Nothing leaves your machine.

One-time purchase.

I'd love feedback, especially edge cases where corrections go wrong.

Comments (1 of ) ⌛

Loading more comments... ⌛
Scroll down to load more comments
No comments available.
Type to search HN and engineering blog articles
Press Escape to close  |  ↑↓ to navigate  |  Enter to open