QuickGPX

macOS Quick Look support for .gpx files:

• Press Space on a GPX file in Finder → the track drawn on a Thunderforest Outdoors base map ("Outdoor" layer), titled with the start location + date, plus a stats bar: distance (km), D+ (cumulative ascent), altitude range, duration (when the file has timestamps), and point count. An elevation profile (altitude vs. distance) is drawn under the map when the file carries elevation data; hovering it shows a crosshair with distance/altitude and marks the spot on the map.

• Finder thumbnails → the track outline drawn as the file's icon.

Legacy .qlgenerator plugins stopped working in macOS 15 (Sequoia), so this is built the modern way: a minimal host app carrying a Quick Look preview extension (QLPreviewingController + MapKit) and a thumbnail extension (QLThumbnailProvider). No Xcode project — everything is compiled with swiftc and assembled by the build script.

Build & install

./build.sh

This compiles, assembles QuickGPX.app, ad-hoc signs it, installs it to ~/Applications, and registers the extensions. Then select any .gpx file in Finder and press Space. Requires Xcode (or at least its toolchain + SDK).

If previews don't appear: check that "QuickGPX" is enabled under System Settings → General → Login Items & Extensions → Quick Look.

Release (distributable build)

./build.sh --release

Signs with Developer ID (hardened runtime + timestamp), notarizes, staples, and writes a distributable dist/QuickGPX-<version>.zip. One-time setup for notarization credentials:

xcrun notarytool store-credentials notary \
    --apple-id <apple-id> --team-id VBYRKYS73S \
    --password <app-specific-password>   # from appleid.apple.com

Not App Store material: the sbpl entitlement below would be rejected by review (notarization, being a malware scan rather than a policy review, accepts it).

Uninstall

rm -rf ~/Applications/QuickGPX.app && qlmanage -r

Layout

Sources/Shared/GPXDocument.swift        GPX parser (trk/rte/wpt) + stats
Sources/Preview/PreviewViewController.swift   map preview extension
Sources/Thumbnail/ThumbnailProvider.swift     thumbnail extension
Sources/App/main.swift                  minimal host app
Config/                                 Info.plists + entitlements
build.sh                                compile, bundle, sign, install, register

Notes on the Quick Look sandbox

Quick Look preview extensions run under the system's quicklook-preview.sb sandbox profile, which denies all networking regardless of the com.apple.security.network.client entitlement. Consequences:

• Apple's own map tiles can never load (GeoServices is blocked), so the map uses an MKTileOverlay with canReplaceMapContent fetching web tiles directly. Thunderforest Outdoors @2x is used because openstreetmap.org serves only 256px tiles, which are blurry at readable label size on Retina (tileSize 512 cancels MapKit's Retina zoom offset).
• The network access needed for those tile fetches is granted through com.apple.security.temporary-exception.sbpl entitlements ((allow network-outbound)), which the profile explicitly honors.
• The title's location comes from OSM Nominatim reverse geocoding (zoom 16); Apple's CLGeocoder needs geod, which the sandbox blocks.

The thumbnail extension needs no network — it draws the track vector directly.

macOS caches aggressively: build.sh runs qlmanage -r, resets the cache, and restarts ThumbnailsAgent, which otherwise keeps serving a stale extension list.