# simonbs/Runestone

📝 Performant plain text editor for iOS with syntax highlighting, line numbers, invisible characters and much more.

Repository: https://github.com/simonbs/Runestone
Canonical: https://ross.abutalabs.com/products/runestone
Language: Swift
License: MIT
License Family: permissive
Topics: ios, swift, tree-sitter
Last push: 2026-03-25T14:57:00+00:00

## Health v2 (maintenance only)
Score: 69/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 74, release rhythm 44, longevity 100
- inputs: {"age_days": 1689, "days_push": 161, "days_rel": 161, "gap_med": null, "n_releases_24m": 1}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3201, forks 220 (observed 2026-08-28T04:07:48.501654+00:00)

## What it is
Runestone is a performant plain text and code editor library for iOS built in Swift. It uses Tree-sitter for syntax highlighting and offers features like line numbers, invisible characters, search, and extensive customization.

## Use cases
- embed a code editor in an iOS app
- syntax-highlighted text editor for Swift/iOS
- show line numbers and invisible characters in a text view
- build an iOS code editor with Tree-sitter parsing
- search text with regular expressions in an editor
- customize fonts and colors of a code editor

## When to choose
- you need a fast, native iOS text/code editor component
- you want Tree-sitter-based syntax highlighting on iOS
- you need fine-grained editor customization like line wrapping, page guides, and line endings

## When to avoid
- you need a cross-platform editor (Android, desktop, web)
- you need a full-featured IDE rather than an embeddable editor component
- your project is not in the Apple/Swift ecosystem

## Facets
- artifact type: library
- maturity: active
- function: editor, ui-components, parser
- domain: text-editors, mobile-development, developer-tools
- platform: -
- tags: syntax-highlighting, tree-sitter, code-editor, textview, line-numbers, ios, swift, mobile

## Member repositories
- simonbs/Runestone (main) score 69

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:48.501654+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T07:24:49.405700+00:00, confidence not recorded.
  - readme: https://github.com/simonbs/Runestone (fetched 2026-08-28T04:07:48.501654+00:00, sha 855e70eeef3d)
- Data as of 2026-08-30T08:39:29.467469+00:00.