NOTICE

Alvyo
Copyright (C) 2026 Adrian Berger and Alvyo contributors
Licensed under the GNU Affero General Public License v3.0 only (AGPL-3.0-only).
Contributions are accepted under the Contributor License Agreement in CLA.md.

Data sources (attribution required when displaying or distributing; terms,
links and where each is credited: docs/licensing.md):
- Maps, aerial images, base map, elevation (swissALTI3D), relief, slopes,
  swissTLM3D hiking trails, place names: © swisstopo (Federal Office of
  Topography swisstopo, free geodata / OGD terms)
- The official hiking routes (national, regional, local, barrier-free) and
  hiking trail closures and diversions: Wanderland Schweiz, ASTRA /
  SchweizMobil (ch.astra.wanderland, ch.astra.wanderland-sperrungen_umleitungen,
  opendata.swiss, open use, source required); named on every route's page
- Reference stages for calibration (swiss/testdata/reference_stages.json):
  Wanderland Schweiz, ASTRA / SchweizMobil (opendata.swiss, open use, source
  required)
- Wildlife rest areas and federal hunting reserves: Federal Office for the
  Environment BAFU and the cantons (opendata.swiss, open use, source required)
- Shooting notices: Federal Department of Defence VBS (ch.vbs.schiessanzeigen,
  opendata.swiss, open use, source required)
- Weather forecasts, rain radar, ICON-CH1 precipitation forecast, climate
  normals 1991–2020: Source: MeteoSwiss (CC BY 4.0)
- Snow cover: Generated using European Union's Copernicus Land Monitoring
  Service information (HR-WSI Gap-filled Fractional Snow Cover,
  doi:10.2909/832c7297-a20f-4b92-8e32-1e2e1548e642), coloured and cut to
  Switzerland by Alvyo (CLMS data policy, Regulation (EU) 1159/2013)
- Public transport connections: opentransportdata.swiss (Open Journey Planner)
- Public transport stops: Federal Office of Transport BAV (list of stops, OGD)
- Routing network, huts, accommodation, places, points of interest and the
  summits of the app's peak pack: © OpenStreetMap contributors (ODbL,
  https://www.openstreetmap.org/copyright), from Geofabrik's extracts. The
  databases Alvyo derives from it are made by the import scripts in
  infra/data-import and are available under the ODbL.
- Terrain for the 3D map and the app's peak pack: Mapterhorn
  (https://mapterhorn.com/attribution), built from Copernicus GLO-30
  (© DLR e.V. 2010–2014 and © Airbus Defence and Space GmbH 2014–2018,
  provided under COPERNICUS by the European Union and ESA), swissALTI3D
  (© swisstopo) and the national elevation models of the neighbouring
  countries (mostly CC BY 4.0 and open government licences)
- Heights in the routing graph (slopes of «Wie weit komme ich?»): Terrain
  Tiles by Mapzen (https://github.com/tilezen/joerd/blob/master/docs/attribution.md);
  Europe: produced using Copernicus data and information funded by the
  European Union – EU-DEM layers; SRTM data courtesy of the U.S. Geological
  Survey

Algorithms:
- Swiss hiking time: SchweizMobil variant of the Schweizer Wanderwege formula,
  as published in geoadmin/mf-geoadmin3 (src/components/profile/ProfileService.js).
  Re-implemented in Go (swiss/hikingtime).

Code derived from third-party projects is listed below with its license.
- HEIC photos are decoded with github.com/gen2brain/heic (MIT), which embeds
  the Rust heic decoder (github.com/imazen/heic, AGPL-3.0-only) compiled to
  WebAssembly.
- api/internal/packs/pmtiles.go: the PMTiles v3 encoding is adapted from
  protomaps/go-pmtiles (BSD-3-Clause, © 2021 Protomaps LLC).
- The OG images are drawn with github.com/fogleman/gg, which uses
  github.com/golang/freetype under the FreeType License: portions of this
  software are copyright © 2010 The FreeType Project (www.freetype.org).
  All rights reserved.

The Android app contains Google's desugar_jdk_libs (parts of OpenJDK,
GPL-2.0 with the Classpath Exception; source at
https://github.com/google/desugar_jdk_libs).

The app contains Firebase (Apache-2.0, https://github.com/firebase) and
Google's measurement libraries for Google Analytics, which are closed
source under Google's terms (https://firebase.google.com/terms).

Fonts: Figtree and Bricolage Grotesque, SIL Open Font License 1.1
(app/assets/fonts/OFL-*.txt; on the website from @fontsource-variable).

The licenses of all other Go, npm and Dart packages are listed by the
commands in docs/licensing.md; the app shows them under «Über Alvyo».