# Gander

> Gander is a Quick Look extension for macOS by 65FN LLC. Select a developer file in Finder and press Space to see a rich preview: Markdown (GitHub-flavoured, with Mermaid diagrams, math, footnotes, alerts and emoji), Mermaid files, JSON and JSON Lines, SQLite databases (read-only), .env files (values hidden until revealed), YAML, TOML, source code, archives, GZIP text, folders and MIDI. It also draws Finder thumbnails. Everything runs locally; no data is collected.

Key facts:

- App Store name: Gander: Quick Look Preview. Publisher: 65FN LLC. Version 1.0.
- Requires macOS 15 or later. Distributed through the Mac App Store (launching soon).
- No subscription and no account.
- Privacy: Data Not Collected. No networking code; the preview and thumbnail extensions run sandboxed without network access.
- How to use: install, open Gander once, then select a file in Finder and press Space. If the standard preview still appears, turn Gander on in System Settings › General › Login Items & Extensions › Quick Look.
- Supported file types (40 extensions): Markdown (.md, .markdown, .mdown, .markdn); Mermaid (.mmd, .mermaid); JSON (.json); JSON Lines (.jsonl, .ndjson); package.json (package.json); YAML (.yaml, .yml); TOML (.toml); Config files (.cfg, .config); SQLite (.sqlite, .sqlite3, .db); Environment files (.env, .env.*, *.env); Source code (.swift, .py, .js, .mjs, .cjs, .sh, .bash, .zsh); Plain text (.txt, .text, .ini, dotfiles, files with no extension); Archives (.zip, .xip, .tar, .tgz, .tar.gz); GZIP (.gz, .gzip); Folders (any folder); MIDI (.mid, .midi, .smf, .kar).
- SQLite databases open read-only and immutable; the preview never writes to the database.
- .env files open with every value hidden until the user chooses Show values; .env thumbnails show keys only.
- Limits: no Gander thumbnails for SQLite, folders, MIDI, XIP or plain .gz (Finder keeps its icon); images inside Markdown show as alt text; SQLite shows up to 200 rows per table; GZIP text up to 32 KB.
- Each file category and each Markdown extra (math, footnotes, GitHub alerts, emoji) can be switched off in the Gander window.

## Pages

- [Gander home](https://ganderfinder.com/index.md): What Gander does, every viewer, supported file types, setup and FAQ
- [Support](https://ganderfinder.com/support.md): Setup, troubleshooting and contact
- [Privacy policy](https://ganderfinder.com/privacy.md): Gander collects no data; what the app, Apple and this website handle

## Español

- [Inicio de Gander](https://ganderfinder.com/es/index.md): Qué hace Gander, cada visor, tipos de archivo, configuración y preguntas
- [Soporte](https://ganderfinder.com/es/support.md): Configuración, solución de problemas y contacto
- [Política de privacidad](https://ganderfinder.com/es/privacy.md): Gander no recopila datos; qué gestionan la app, Apple y este sitio web

## Optional

- [llms-full.txt](https://ganderfinder.com/llms-full.txt): Full text of the English pages in one file
- [App preview video](https://ganderfinder.com/video/gander-tour-en.mp4): App preview video (29 s); a written description is on the home page
- [Screenshots](https://ganderfinder.com/img/screens/en/01-hero.jpg): Mac App Store screenshots, 01-hero.jpg to 10-private.jpg in the same folder